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• SQL SERVER – Beginning of SQL Server Architecture – Terminology – Guest Post

  - by pinaldave

  SQL Server Architecture is a very deep subject. Covering it in a single post is an almost impossible task. However, this subject is very popular topic among beginners and advanced users.  I have requested my friend Anil Kumar who is expert in SQL Domain to help me write  a simple post about Beginning SQL Server Architecture. As stated earlier this subject is very deep subject and in this first article series he has covered basic terminologies. In future article he will explore the subject further down. Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. In this Article we will discuss about MS SQL Server architecture. The major components of SQL Server are: Relational Engine Storage Engine SQL OS Now we will discuss and understand each one of them. 1) Relational Engine: Also called as the query processor, Relational Engine includes the components of SQL Server that determine what your query exactly needs to do and the best way to do it. It manages the execution of queries as it requests data from the storage engine and processes the results returned. Different Tasks of Relational Engine: Query Processing Memory Management Thread and Task Management Buffer Management Distributed Query Processing 2) Storage Engine: Storage Engine is responsible for storage and retrieval of the data on to the storage system (Disk, SAN etc.). to understand more, let’s focus on the following diagram. When we talk about any database in SQL server, there are 2 types of files that are created at the disk level – Data file and Log file. Data file physically stores the data in data pages. Log files that are also known as write ahead logs, are used for storing transactions performed on the database. Let’s understand data file and log file in more details: Data File: Data File stores data in the form of Data Page (8KB) and these data pages are logically organized in extents. Extents: Extents are logical units in the database. They are a combination of 8 data pages i.e. 64 KB forms an extent. Extents can be of two types, Mixed and Uniform. Mixed extents hold different types of pages like index, System, Object data etc. On the other hand, Uniform extents are dedicated to only one type. Pages: As we should know what type of data pages can be stored in SQL Server, below mentioned are some of them: Data Page: It holds the data entered by the user but not the data which is of type text, ntext, nvarchar(max), varchar(max), varbinary(max), image and xml data. Index: It stores the index entries. Text/Image: It stores LOB ( Large Object data) like text, ntext, varchar(max), nvarchar(max),  varbinary(max), image and xml data. GAM & SGAM (Global Allocation Map & Shared Global Allocation Map): They are used for saving information related to the allocation of extents. PFS (Page Free Space): Information related to page allocation and unused space available on pages. IAM (Index Allocation Map): Information pertaining to extents that are used by a table or index per allocation unit. BCM (Bulk Changed Map): Keeps information about the extents changed in a Bulk Operation. DCM (Differential Change Map): This is the information of extents that have modified since the last BACKUP DATABASE statement as per allocation unit. Log File: It also known as write ahead log. It stores modification to the database (DML and DDL). Sufficient information is logged to be able to: Roll back transactions if requested Recover the database in case of failure Write Ahead Logging is used to create log entries Transaction logs are written in chronological order in a circular way Truncation policy for logs is based on the recovery model SQL OS: This lies between the host machine (Windows OS) and SQL Server. All the activities performed on database engine are taken care of by SQL OS. It is a highly configurable operating system with powerful API (application programming interface), enabling automatic locality and advanced parallelism. SQL OS provides various operating system services, such as memory management deals with buffer pool, log buffer and deadlock detection using the blocking and locking structure. Other services include exception handling, hosting for external components like Common Language Runtime, CLR etc. I guess this brief article gives you an idea about the various terminologies used related to SQL Server Architecture. In future articles we will explore them further. Guest Author  The author of the article is Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

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• SQL SERVER – SSMS: Memory Usage By Memory Optimized Objects Report

  - by Pinal Dave

  At conferences and at speaking engagements at the local UG, there is one question that keeps on coming which I wish were never asked. The question around, “Why is SQL Server using up all the memory and not releasing even when idle?” Well, the answer can be long and with the release of SQL Server 2014, this got even more complicated. This release of SQL Server 2014 has the option of introducing In-Memory OLTP which is completely new concept and our dependency on memory has increased multifold. In reality, nothing much changes but we have memory optimized objects (Tables and Stored Procedures) additional which are residing completely in memory and improving performance. As a DBA, it is humanly impossible to get a hang of all the innovations and the new features introduced in the next version. So today’s blog is around the report added to SSMS which gives a high level view of this new feature addition. This reports is available only from SQL Server 2014 onwards because the feature was introduced in SQL Server 2014. Earlier versions of SQL Server Management Studio would not show the report in the list. If we try to launch the report on the database which is not having In-Memory File group defined, then we would see the message in report. To demonstrate, I have created new fresh database called MemoryOptimizedDB with no special file group. Here is the query used to identify whether a database has memory-optimized file group or not. SELECT TOP(1) 1 FROM sys.filegroups FG WHERE FG.[type] = 'FX' Once we add filegroup using below command, we would see different version of report. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILEGROUP [IMO_FG] CONTAINS MEMORY_OPTIMIZED_DATA GO The report is still empty because we have not defined any Memory Optimized table in the database.  Total allocated size is shown as 0 MB. Now, let’s add the folder location into the filegroup and also created few in-memory tables. We have used the nomenclature of IMO to denote “InMemory Optimized” objects. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILE ( NAME = N'MemoryOptimizedDB_IMO', FILENAME = N'E:\Program Files\Microsoft SQL Server\MSSQL12.SQL2014\MSSQL\DATA\MemoryOptimizedDB_IMO') TO FILEGROUP [IMO_FG] GO You may have to change the path based on your SQL Server configuration. Below is the script to create the table. USE MemoryOptimizedDB GO --Drop table if it already exists. IF OBJECT_ID('dbo.SQLAuthority','U') IS NOT NULL DROP TABLE dbo.SQLAuthority GO CREATE TABLE dbo.SQLAuthority ( ID INT IDENTITY NOT NULL, Name CHAR(500)  COLLATE Latin1_General_100_BIN2 NOT NULL DEFAULT 'Pinal', CONSTRAINT PK_SQLAuthority_ID PRIMARY KEY NONCLUSTERED (ID), INDEX hash_index_sample_memoryoptimizedtable_c2 HASH (Name) WITH (BUCKET_COUNT = 131072) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO As soon as above script is executed, table and index both are created. If we run the report again, we would see something like below. Notice that table memory is zero but index is using memory. This is due to the fact that hash index needs memory to manage the buckets created. So even if table is empty, index would consume memory. More about the internals of how In-Memory indexes and tables work will be reserved for future posts. Now, use below script to populate the table with 10000 rows INSERT INTO SQLAuthority VALUES (DEFAULT) GO 10000 Here is the same report after inserting 1000 rows into our InMemory table.    There are total three sections in the whole report. Total Memory consumed by In-Memory Objects Pie chart showing memory distribution based on type of consumer – table, index and system. Details of memory usage by each table. The information about all three is taken from one single DMV, sys.dm_db_xtp_table_memory_stats This DMV contains memory usage statistics for both user and system In-Memory tables. If we query the DMV and look at data, we can easily notice that the system tables have negative object IDs.  So, to look at user table memory usage, below is the over-simplified version of query. USE MemoryOptimizedDB GO SELECT OBJECT_NAME(OBJECT_ID), * FROM sys.dm_db_xtp_table_memory_stats WHERE OBJECT_ID > 0 GO This report would help DBA to identify which in-memory object taking lot of memory which can be used as a pointer for designing solution. I am sure in future we will discuss at lengths the whole concept of In-Memory tables in detail over this blog. To read more about In-Memory OLTP, have a look at In-Memory OLTP Series at Balmukund’s Blog. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Memory, SQL Reports

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• Can't install wine (or ia32-libs) in Ubuntu 12.10 64 bit

  - by carestad

  As already pointed out here, people seems to have issues with installing wine in the latest version of Ubuntu. I'm suspecting this only happens with 64 bit users. For example, when trying to install wine, wine1.4, wine1.4:i386, wine1.5, wine1.5:i386, ia32-libs or ia32-libs:i386 with apt-get, I get a lot of dependency errors. Doing a sudo apt-get -f install doesn't seem to do the trick, neither does using aptitude. The errors I get is normally that the packages depend on some :i386 package, but installing those manually doesn't work either because they also have dependency issues (isn't APT supposed to do this automatically?!). I also downloaded CrossOver today and tried installing the .deb manually, but the dependency issues show up there as well. When running sudo apt-get -f install after trying to install the CrossOver .deb, apt-get wants to purge the following packages: ia32-crossover intel-gpu-tools libdrm-nouveau2 libgl1-mesa-dri libva-x11-1 ubuntu-desktop vlc xorg xserver-xorg-video-ati xserver-xorg-video-intel xserver-xorg-video-modesetting xserver-xorg-video-openchrome xserver-xorg-video-radeon xserver-xorg-video-vmware What I've tried so far (and didn't work): Installing synaptic, reloading my repositories, searching for ia32 and installing ia32-libs. Using Ubuntu Software Center to install Wine and ia32-libs. Using apt-get and aptitude to install all the differend varieties of the wine packages, both with and without the :i386 and -amd64 suffixes in package names. Disabling the universe and multiverse repos, run a sudo apt-get update and then re-enable them again. Boot a newly downloaded Ubuntu 12.10 x64 live USB and try to install all the different packages there. What I haven't tried (yet): Boot a newly downloaded Ubuntu 12.10 x32 image and try to install wine there (I'm just guessing that will work). Reinstall Ubuntu. Throw my computer out a window. wine alexander@cosmo:~$ LANGUAGE=en_US sudo apt-get install wine Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: wine : Depends: wine1.5 but it is not going to be installed E: Unable to correct problems, you have held broken packages. wine-1.4 alexander@cosmo:~$ LANGUAGE=en_US sudo apt-get install wine1.4 (...) The following packages have unmet dependencies: wine1.4 : Depends: wine1.4-i386 (= 1.4.1-0ubuntu1) E: Unable to correct problems, you have held broken packages. wine-1.4:i386 alexander@cosmo:~$ LANGUAGE=en_US sudo apt-get install wine1.4:i386 (...) The following packages have unmet dependencies: libaudio2:i386 : Depends: libxt6:i386 but it is not going to be installed libqtgui4:i386 : Depends: libsm6:i386 but it is not going to be installed libunity-webapps0 : Depends: unity-webapps-service but it is not going to be installed openssh-client : Depends: adduser (>= 3.10) but it is not going to be installed Depends: passwd ssh : Depends: openssh-server wine1.4:i386 : Depends: wine1.4-i386:i386 (= 1.4.1-0ubuntu1) Depends: binfmt-support:i386 (>= 1.1.2) Depends: procps:i386 Recommends: cups-bsd:i386 Recommends: gnome-exe-thumbnailer:i386 but it is not installable or kde-runtime:i386 but it is not going to be installed Recommends: ttf-droid:i386 but it is not installable Recommends: ttf-liberation:i386 but it is not installable Recommends: ttf-mscorefonts-installer:i386 Recommends: ttf-umefont:i386 but it is not installable Recommends: ttf-unfonts-core:i386 but it is not installable Recommends: ttf-wqy-microhei:i386 but it is not installable Recommends: winbind:i386 Recommends: winetricks:i386 but it is not going to be installed Recommends: xdg-utils:i386 but it is not installable E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages. wine-1.5 alexander@cosmo:~$ sudo apt-get install wine1.5 (...) The following packages have unmet dependencies: wine1.5 : Depends: wine1.5-i386 (= 1.5.16-0ubuntu1) E: Unable to correct problems, you have held broken packages. wine-1.5:i386 alexander@cosmo:~$ sudo apt-get install wine1.5:i386 (...) The following packages have unmet dependencies: libaudio2:i386 : Depends: libxt6:i386 but it is not going to be installed libqtgui4:i386 : Depends: libsm6:i386 but it is not going to be installed libunity-webapps0 : Depends: unity-webapps-service but it is not going to be installed openssh-client : Depends: adduser (>= 3.10) but it is not going to be installed Depends: passwd ssh : Depends: openssh-server wine1.5:i386 : Depends: wine1.5-i386:i386 (= 1.5.16-0ubuntu1) but it is not going to be installed Depends: binfmt-support:i386 (>= 1.1.2) Depends: procps:i386 Recommends: cups-bsd:i386 Recommends: gnome-exe-thumbnailer:i386 but it is not installable or kde-runtime:i386 but it is not going to be installed Recommends: ttf-droid:i386 but it is not installable Recommends: ttf-liberation:i386 but it is not installable Recommends: ttf-mscorefonts-installer:i386 Recommends: ttf-umefont:i386 but it is not installable Recommends: ttf-unfonts-core:i386 but it is not installable Recommends: ttf-wqy-microhei:i386 but it is not installable Recommends: winbind:i386 Recommends: winetricks:i386 but it is not going to be installed Recommends: xdg-utils:i386 but it is not installable E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages. ia32-libs alexander@cosmo:~$ sudo apt-get install ia32-libs (...) The following packages have unmet dependencies: ia32-libs : Depends: ia32-libs-multiarch E: Unable to correct problems, you have held broken packages. ia32-libs:i386 alexander@cosmo:~$ sudo apt-get install ia32-libs:i386 (...) Package ia32-libs:i386 is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it: lib32z1 lib32ncurses5 lib32bz2-1.0 lib32asound2 E: Package 'ia32-libs:i386' has no installation candidate

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• SQLAuthority News – Technology and Online Learning – Personal Technology Tip

  - by pinaldave

  This is the fourth post in my series about Personal Technology Tips and Tricks, and I knew exactly what I wanted to write about.  But at first I was conflicted.   Is online learning really a personal tip?  Is it really a trick that no one knows?  However, I have decided to stick with my original idea because online learning is everywhere.  It’s a trick that we can’t – and shouldn’t – overlook.  Here are ten of my ideas about how we should be taking advantage of online learning. 1) Get ahead in the work place.  We all know that a good way to become better at your job, and to become more competitive for promotions and raises.  Many people overlook online learning as a way to get job training, though, thinking it is a path for people still seeking their high school or college diplomas.  But take a look at what companies like Pluralsight offer, and you might be pleasantly surprised. 2) Flexibility.  Some of us remember the heady days of college with nostalgia, others remember it with loathing.  A lot of bad memories come from remembering the strict scheduling and deadlines of college.  But with online learning, the classes fit into your free time – you don’t have to schedule your life around classes.  Even better, there are usually no homework or test deadlines, only one final deadline where all work must be completed.  This allows students to work at their own pace – my next point. 3) Learn at your own pace.  One thing traditional classes suffer from is that they are highly structured.  If you work more quickly than the rest of the class, or especially if you work more slowly, traditional classes do not work for you.  Online courses let you move as quickly or as slowly as you find necessary. 4) Fill gaps in your knowledge.  I’m sure I am not the only one who has thought to myself “I would love to take a course on X, Y, or Z.”  The problem is that it can be very hard to find the perfect class that teaches exactly what you’re interested in, at a time and a price that’s right.  But online courses are far easier to tailor exactly to your tastes. 5) Fits into your schedule.  Even harder to find than a class you’re interested in is one that fits into your schedule.  If you hold down a job – even a part time job – you know it’s next to impossible to find class times that work for you.  Online classes can be taken anytime, anywhere.  On your lunch break, in your car, or in your pajamas at the end of the day. 6) Student centered.  Online learning has to stay competitive.  There are hundreds, even thousands of options for students, and every provider has to find a way to lure in students and provide them with a good education.  The best kind of online classes know that they need to provide great classes, flexible scheduling, and high quality to attract students – and the student benefit from this kind of attention. 7) You can save money.  The average cost for a college diploma in the US is over $20,000.  I don’t know about you, but that is not the kind of money I just have lying around for a rainy day.  Sometimes I think I’d love to go back to school, but not for that price tag.  Online courses are much, much more affordable.  And even better, you can pick and choose what courses you’d like to take, and avoid all the “electives” in college. 8) Get access to the best minds in the business.  One of the perks of being the best in your field is that you are one person who knows the most about something.  If students are lucky, you will choose to share that knowledge with them on a college campus.  For the hundreds of other students who don’t live in your area and don’t attend your school, they are out of luck.  But luckily for them, more and more online courses is attracting the best minds in the business, and if you enroll online, you can take advantage of these minds, too. 9) Save your time.  Getting a four year degree is a great decision, and I encourage everyone to pursue their Bachelor’s – and beyond.  But if you have already tried to go to school, or already have a degree but are thinking of switching fields, four years of your life is a long time to go back and redo things.  Getting your online degree will save you time by allowing you to work at your own pace, set your own schedule, and take only the classes you’re interested in. 10) Variety of degrees and programs.  If you’re not sure what you’re interested in, or if you only need a few classes here and there to finish a program, online classes are perfect for you.  You can pick and choose what you’d like, and sample a wide variety without spending too much money. I hope I’ve outlined for everyone just a few ways that they could benefit from online learning.  If you’re still unconvinced, just check out a few of my other articles that expand more on these topics. Here are the blog posts relevent to developer trainings: Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Developer Training

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• Change the User Interface Language in Vista or Windows 7

  - by Matthew Guay

  Would you like to change the user interface language in any edition of Windows 7 or Vista on your computer?  Here’s a free app that can help you do this quickly and easily. If your native language is not the one most spoken in your area, you’ve likely purchased a PC with Windows preinstalled with a language that is difficult or impossible for you to use.  Windows 7 and Vista Ultimate include the ability to install multiple user interface languages and switch between them. However, all other editions are stuck with the language they shipped with.  With the free Vistalizator app, you can add several different interface languages to any edition of Vista or Windows 7 and easily switch between them. Note:  In this test, we used an US English copy of both Windows 7 Home Premium and Windows Vista Home Premium, and it works the same on any edition. The built-in language switching in the Ultimate Editions lets you set a user interface language for each user account, but this will only switch it for all users.  Add a User Interface Language to Windows To add an interface language to any edition of Windows 7 and Vista, first download Vistalizator (link below).  Then, from the same page, download the language pack of your choice.  The language packs are specific for each service pack of Windows, so make sure to choose the correct version and service pack you have installed. Once the downloads are finished, launch the Vistalizator program. You do not need to install it; simply run it and you’re ready to go.  Click the Add languages button to add a language to Windows. Select the user interface language pack you downloaded, and click Open. Depending on the language you selected, it may not automatically update with Windows Update when a service pack is released.  If so, you will have to remove the language pack and reinstall the new one for that service pack at that time.  Click Ok to continue. Make sure you’ve selected the correct language, and click Install language. Vistalizator will extract and install the language pack.  This took around 5 to 10 minutes in our test. Once the language pack is installed, click Yes to make it the default display language. Now, you have two languages installed in Windows.  You may be prompted to check for updates to the language pack; if so, click Update languages and Vistalizator will automatically check for and install any updates. When finished, exit Vistalizator to finish switching the language.  Click Yes to automatically reboot and apply the changes. When you computer reboots, it will show your new language, which in our test is Thai.  Here’s our Windows 7 Home Premium machine with the Thai language pack installed and running. You can even add a right to left language, such as Arabic, to Windows.  Simply repeat the steps to add another language pack.    Vistalizator was originally designed for Windows Vista, and works great with Windows 7 too.  The language packs for Vista are larger downloads than their Windows 7 counterparts.  Here’s our Vista Home Premium in English… And here’s how it looks after installing the Simplified Chinese language pack with Vistalizator. Revert to Your Original Language If you wish to return to the language that your computer shipped with, or want to switch to another language you’ve installed, run Vistalizator again.  Select the language you wish to use, and click Change language.   When you close Vistalizator, you will again be asked to reboot.  Once you’ve rebooted, you’ll see your new (or original) language ready to use.  Here’s our Windows 7 Home Premium desktop, back in it’s original English interface. Conclusion This is a great way to change your computer’s language into your own native language, and is especially useful for expatriates around the world.  Also, if you’d like to simply change or add an input language instead of changing the language throughout your computer, check out our tutorial on How to Add Keyboard Languages to XP, Vista, and Windows 7. Download Vistalizator Similar Articles Productive Geek Tips Enable Military Time in Windows 7 or VistaWhy Does My Password Expire in Windows?Use Windows Vista Aero through Remote Desktop ConnectionDisable User Account Control (UAC) the Easy Way on Win 7 or VistaAdd keyboard languages to XP, Vista, and Windows 7 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Home Networks – How do they look like & the problems they cause Check Your IMAP Mail Offline In Thunderbird Follow Finder Finds You Twitter Users To Follow Combine MP3 Files Easily QuicklyCode Provides Cheatsheets & Other Programming Stuff Download Free MP3s from Amazon

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• Open Source but not Free Software (or vice versa)

  - by TRiG

  The definition of "Free Software" from the Free Software Foundation: “Free software” is a matter of liberty, not price. To understand the concept, you should think of “free” as in “free speech,” not as in “free beer.” Free software is a matter of the users' freedom to run, copy, distribute, study, change and improve the software. More precisely, it means that the program's users have the four essential freedoms: The freedom to run the program, for any purpose (freedom 0). The freedom to study how the program works, and change it to make it do what you wish (freedom 1). Access to the source code is a precondition for this. The freedom to redistribute copies so you can help your neighbor (freedom 2). The freedom to distribute copies of your modified versions to others (freedom 3). By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this. A program is free software if users have all of these freedoms. Thus, you should be free to redistribute copies, either with or without modifications, either gratis or charging a fee for distribution, to anyone anywhere. Being free to do these things means (among other things) that you do not have to ask or pay for permission to do so. The definition of "Open Source Software" from the Open Source Initiative: Open source doesn't just mean access to the source code. The distribution terms of open-source software must comply with the following criteria: Free Redistribution The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale. Source Code The program must include source code, and must allow distribution in source code as well as compiled form. Where some form of a product is not distributed with source code, there must be a well-publicized means of obtaining the source code for no more than a reasonable reproduction cost preferably, downloading via the Internet without charge. The source code must be the preferred form in which a programmer would modify the program. Deliberately obfuscated source code is not allowed. Intermediate forms such as the output of a preprocessor or translator are not allowed. Derived Works The license must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software. Integrity of The Author's Source Code The license may restrict source-code from being distributed in modified form only if the license allows the distribution of "patch files" with the source code for the purpose of modifying the program at build time. The license must explicitly permit distribution of software built from modified source code. The license may require derived works to carry a different name or version number from the original software. No Discrimination Against Persons or Groups The license must not discriminate against any person or group of persons. No Discrimination Against Fields of Endeavor The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research. Distribution of License The rights attached to the program must apply to all to whom the program is redistributed without the need for execution of an additional license by those parties. License Must Not Be Specific to a Product The rights attached to the program must not depend on the program's being part of a particular software distribution. If the program is extracted from that distribution and used or distributed within the terms of the program's license, all parties to whom the program is redistributed should have the same rights as those that are granted in conjunction with the original software distribution. License Must Not Restrict Other Software The license must not place restrictions on other software that is distributed along with the licensed software. For example, the license must not insist that all other programs distributed on the same medium must be open-source software. License Must Be Technology-Neutral No provision of the license may be predicated on any individual technology or style of interface. These definitions, although they derive from very different ideologies, are broadly compatible, and most Free Software is also Open Source Software and vice versa. I believe, however, that it is possible for this not to be the case: It is possible for software to be Open Source without being Free, or to be Free without being Open Source. Questions Is my belief correct? Is it possible for software to fall into one camp and not the other? Does any such software actually exist? Please give examples. Clarification I've already accepted an answer now, but I seem to have confused a lot of people, so perhaps a clarification is in order. I was not asking about the difference between copyleft (or "viral", though I don't like that term) and non-copyleft ("permissive") licenses. Nor was I asking about your personal idiosyncratic definitions of "Free" and "Open". I was asking about "Free Software as defined by the FSF" and "Open Source Software as defined by the OSI". Are the two always the same? Is it possible to be one without being the other? And the answer, it seems, is that it's impossible to be Free without being Open, but possible to be Open without being Free. Thank you everyone who actually answered the question.

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• JavaScript Intellisense Improvements with VS 2010

  - by ScottGu

  This is the twentieth in a series of blog posts I’m doing on the upcoming VS 2010 and .NET 4 release.  Today’s blog post covers some of the nice improvements coming with JavaScript intellisense with VS 2010 and the free Visual Web Developer 2010 Express.  You’ll find with VS 2010 that JavaScript Intellisense loads much faster for large script files and with large libraries, and that it now provides statement completion support for more advanced scenarios compared to previous versions of Visual Studio. [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Improved JavaScript Intellisense Providing Intellisense for a dynamic language like JavaScript is more involved than doing so with a statically typed language like VB or C#.  Correctly inferring the shape and structure of variables, methods, etc is pretty much impossible without pseudo-executing the actual code itself – since JavaScript as a language is flexible enough to dynamically modify and morph these things at runtime.  VS 2010’s JavaScript code editor now has the smarts to perform this type of pseudo-code execution as you type – which is how its intellisense completion is kept accurate and complete.  Below is a simple walkthrough that shows off how rich and flexible it is with the final release. Scenario 1: Basic Type Inference When you declare a variable in JavaScript you do not have to declare its type.  Instead, the type of the variable is based on the value assigned to it.  Because VS 2010 pseudo-executes the code within the editor, it can dynamically infer the type of a variable, and provide the appropriate code intellisense based on the value assigned to a variable. For example, notice below how VS 2010 provides statement completion for a string (because we assigned a string to the “foo” variable): If we later assign a numeric value to “foo” the statement completion (after this assignment) automatically changes to provide intellisense for a number: Scenario 2: Intellisense When Manipulating Browser Objects It is pretty common with JavaScript to manipulate the DOM of a page, as well as work against browser objects available on the client.  Previous versions of Visual Studio would provide JavaScript statement completion against the standard browser objects – but didn’t provide much help with more advanced scenarios (like creating dynamic variables and methods).  VS 2010’s pseudo-execution of code within the editor now allows us to provide rich intellisense for a much broader set of scenarios. For example, below we are using the browser’s window object to create a global variable named “bar”.  Notice how we can now get intellisense (with correct type inference for a string) with VS 2010 when we later try and use it: When we assign the “bar” variable as a number (instead of as a string) the VS 2010 intellisense engine correctly infers its type and modifies statement completion appropriately to be that of a number instead: Scenario 3: Showing Off Because VS 2010 is psudo-executing code within the editor, it is able to handle a bunch of scenarios (both practical and wacky) that you throw at it – and is still able to provide accurate type inference and intellisense. For example, below we are using a for-loop and the browser’s window object to dynamically create and name multiple dynamic variables (bar1, bar2, bar3…bar9).  Notice how the editor’s intellisense engine identifies and provides statement completion for them: Because variables added via the browser’s window object are also global variables – they also now show up in the global variable intellisense drop-down as well: Better yet – type inference is still fully supported.  So if we assign a string to a dynamically named variable we will get type inference for a string.  If we assign a number we’ll get type inference for a number.  Just for fun (and to show off!) we could adjust our for-loop to assign a string for even numbered variables (bar2, bar4, bar6, etc) and assign a number for odd numbered variables (bar1, bar3, bar5, etc): Notice above how we get statement completion for a string for the “bar2” variable.  Notice below how for “bar1” we get statement completion for a number:   This isn’t just a cool pet trick While the above example is a bit contrived, the approach of dynamically creating variables, methods and event handlers on the fly is pretty common with many Javascript libraries.  Many of the more popular libraries use these techniques to keep the size of script library downloads as small as possible.  VS 2010’s support for parsing and pseudo-executing libraries that use these techniques ensures that you get better code Intellisense out of the box when programming against them. Summary Visual Studio 2010 (and the free Visual Web Developer 2010 Express) now provide much richer JavaScript intellisense support.  This support works with pretty much all popular JavaScript libraries.  It should help provide a much better development experience when coding client-side JavaScript and enabling AJAX scenarios within your ASP.NET applications. Hope this helps, Scott P.S. You can read my previous blog post on VS 2008’s JavaScript Intellisense to learn more about our previous JavaScript intellisense (and some of the scenarios it supported).  VS 2010 obviously supports all of the scenarios previously enabled with VS 2008.

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• 2d movement solution

  - by Phil

  Hi! I'm making a simple top-down tank game on the ipad where the user controls the movement of the tank with the left "joystick" and the rotation of the turret with the right one. I've spent several hours just trying to get it to work decently but now I turn to the pros :) I have two referencial objects, one for the movement and one for the rotation. The referencial objects always stay max two units away from the tank and I use them to tell the tank in what direction to move. I chose this approach to decouple movement and rotational behaviour from the raw input of the joysticks, I believe this will make it simpler to implement whatever behaviour I want for the tank. My problem is 1; the turret rotates the long way to the target. With this I mean that the target can be -5 degrees away in rotation and still it rotates 355 degrees instead of -5 degrees. I can't figure out why. The other problem is with the movement. It just doesn't feel right to have the tank turn while moving. I'd like to have a solution that would work as well for the AI as for the player. A blackbox function for the movement where the player only specifies in what direction it should move and it moves there under the constraints that are imposed on it. I am using the standard joystick class found in the Unity iPhone package. This is the code I'm using for the movement: public class TankFollow : MonoBehaviour { //Check angle difference and turn accordingly public GameObject followPoint; public float speed; public float turningSpeed; void Update() { transform.position = Vector3.Slerp(transform.position, followPoint.transform.position, speed * Time.deltaTime); //Calculate angle var forwardA = transform.forward; var forwardB = (followPoint.transform.position - transform.position); var angleA = Mathf.Atan2(forwardA.x, forwardA.z) * Mathf.Rad2Deg; var angleB = Mathf.Atan2(forwardB.x, forwardB.z) * Mathf.Rad2Deg; var angleDiff = Mathf.DeltaAngle(angleA, angleB); //print(angleDiff.ToString()); if (angleDiff > 5) { //Rotate to transform.Rotate(new Vector3(0, (-turningSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else if (angleDiff < 5) { transform.Rotate(new Vector3(0, (turningSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else { } transform.position = new Vector3(transform.position.x, 0, transform.position.z); } } And this is the code I'm using to rotate the turret: void LookAt() { var forwardA = -transform.right; var forwardB = (toLookAt.transform.position - transform.position); var angleA = Mathf.Atan2(forwardA.x, forwardA.z) * Mathf.Rad2Deg; var angleB = Mathf.Atan2(forwardB.x, forwardB.z) * Mathf.Rad2Deg; var angleDiff = Mathf.DeltaAngle(angleA, angleB); //print(angleDiff.ToString()); if (angleDiff - 180 > 1) { //Rotate to transform.Rotate(new Vector3(0, (turretSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else if (angleDiff - 180 < -1) { transform.Rotate(new Vector3(0, (-turretSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); print((angleDiff - 180).ToString()); } else { } } Since I want the turret reference point to turn in relation to the tank (when you rotate the body, the turret should follow and not stay locked on since it makes it impossible to control when you've got two thumbs to work with), I've made the TurretFollowPoint a child of the Turret object, which in turn is a child of the body. I'm thinking that I'm making it too difficult for myself with the reference points but I'm imagining that it's a good idea. Please be honest about this point. So I'll be grateful for any help I can get! I'm using Unity3d iPhone. Thanks!

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• CQRS - Benefits

  - by Dylan Smith

  Thanks to all the comments and feedback from the last post I think I have a better understanding now of the benefits of CQRS (separate from the benefits of Event Sourcing). I’m going to try and sum it up here, and point out some areas where I could still use some advice: CQRS Benefits Sounds like the primary benefit of CQRS as an architecture is it allows you to create a simpler domain model by sucking out everything related to queries. I can definitely see the benefit to this, in general the domain logic related to commands is the high-value behavior in the software, but the logic required to service the queries would add a lot of low-value “noise” to the domain model that would dilute the high-value (command) behavior – sorting, paging, filtering, pre-fetch paths, etc. Also the most appropriate domain structure for implementing commands might not be the most optimal for implementing queries. To paraphrase Greg, this usually results in a domain model that is mediocre at both, piss-poor at one, or more likely piss-poor at both commands and queries. Not only will you be able to simplify your domain model by pulling out all the query logic, but at least a handful of commands in most systems will probably be “pass-though” type commands with little to no logic that just generate events. If these can be implemented directly in the command-handler and never touch the domain model, this allows you to slim down the domain model even more. Also, if you were to do event sourcing without CQRS, you no longer have a database containing the current state (only the domain model would) which makes it difficult (or impossible) to support ad-hoc querying and/or reporting that is common in most business software. Of course CQRS provides some great scalability benefits, not only scalability but I have to assume that it provides extremely low latency for most operations, especially if you have an asynchronous event bus. I know Greg says that you get a 3x scaling (Commands, Queries, Client) of your ability to perform parallel development, but IMHO, it seems like it only provides 1.5x scaling since even without CQRS you’re going to have your client loosely coupled to your domain - which is still a great benefit to be able to realize. Questions / Concerns If all the queries against an aggregate get pulled out to the Query layer, what if the only commands for that aggregate can be handled in a “pass-through” manner with the command handler directly generating events. Is it possible to have an aggregate that isn’t modeled in the domain model? Are there any issues or downsides to this? I know in the feedback from my previous posts it was suggested that having one domain model handling both commands and queries requires implementing a lot of traversals between objects that wouldn’t be necessary if it was only servicing commands. My question is, do you include traversals in your domain model based on the needs of the code, or based on the conceptual domain model? If none of my Commands require a Customer.Orders traversal, but the conceptual domain includes the concept of a set of orders belonging to a customer – should I model that in my domain model or not? I like the idea of using the Query side of the architecture as a place to put junior devs where the risk of them screwing something up has minimal impact. But I’m not sold on the idea that you can actually outsource it. Like I said in one of my comments on my previous post, the code to handle a query and generate DTO’s is going to be dead simple, but the code to process events and apply them to the tables on the query side is going to require a significant amount of domain knowledge to know which events to listen for to update each of the de-normalized tables (and what changes need to be made when each event is processed). I don’t know about everybody else, but having Indian/Russian/whatever outsourced developers have to do anything that requires significant domain knowledge has never been successful in my experience. And if you need to spec out for each new query which events to listen to and what to do with each one, well that’s probably going to be just as much work to document as it would be to just implement it. Greg made the point in a comment that doing an aggregate query like “Total Sales By Customer” is going to be inefficient if you use event sourcing but not CQRS. I don’t understand why that would be the case. I imagine in that case you’d simply have a method/property on the Customer object that calculated total sales for that customer by enumerating over the Orders collection. Then the application services layer would generate DTO’s off of the Customers collection that included say the CustomerID, CustomerName, TotalSales, or whatever the case may be. As long as you use a snapshotting implementation, I don’t see why that would be anymore inefficient in a DDD+Event Sourcing implementation than in a typical DDD implementation. Like I mentioned in my last post I still have some questions about query logic that haven’t been answered yet, but before I start asking those I want to make sure I have a strong grasp on what benefits CQRS provides.  My main concern with the query logic was that I know I could just toss it all into the query side, but I was concerned that I would be losing the benefits of using CQRS in the first place if I did that.  I want to elaborate more on this though with some example situations in an upcoming post.

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• SQL SERVER – An Efficiency Tool to Compare and Synchronize SQL Server Databases

  - by Pinal Dave

  There is no need to reinvent the wheel if it is already invented and if the wheel is already available at ease, there is no need to wait to grab it. Here is the similar situation. I came across a very interesting situation and I had to look for an efficient tool which can make my life easier and solve my business problem. Here is the scenario. One of the developers had deleted few rows from the very important mapping table of our development server (thankfully, it was not the production server). Though it was a development server, the entire development team had to stop working as the application started to crash on every page. Think about the lost of manpower and efficiency which we started to loose.  Pretty much every department had to stop working as our internal development application stopped working. Thankfully, we even take a backup of our development server and we had access to full backup of the entire database at 6 AM morning. We do not take as a frequent backup of development server as production server (naturally!). Even though we had a full backup, the solution was not to restore the database. Think about it, there were plenty of the other operations since the last good full backup and if we restore a full backup, we will pretty much overwrite on the top of the work done by developers since morning. Now, as restoring the full backup was not an option we decided to restore the same database on another server. Once we had restored our database to another server, the challenge was to compare the table from where the database was deleted. The mapping table from where the data were deleted contained over 5000 rows and it was humanly impossible to compare both the tables manually. Finally we decided to use efficiency tool dbForge Data Compare for SQL Server from DevArt. dbForge Data Compare for SQL Server is a powerful, fast and easy to use SQL compare tool, capable of using native SQL Server backups as metadata source. (FYI we Downloaded dbForge Data Compare) Once we discovered the product, we immediately downloaded the product and installed on our development server. After we installed the product, we were greeted with the following screen. We clicked on the New Data Comparision to start our new comparison project. It brought up following screen. Here is the best part of the product, we just had to enter our database connection username and password along with source and destination details and we are done. The entire process is very simple and self intuiting. The best part was that for the source, we can either select database or even backup. This was indeed fantastic feature. Think about this, if you have a very big database, it will take long time to restore on the server. Once it is restored, you will be able to work with it. However, when you are working with dbForge Data Compare it will accept database backup as your source or destination. Once I click on the execute it brought up following screen where it displayed an excellent summary of the data compare. It has dedicated tabs for the what is changing in what table as well had details of the changed data. The best part is that, once we had reviewed the change. We click on the Synchronize button in the menu bar and it brought up following screen. You can see that the screen has very simple straight forward but very powerful features. You can generate a script to synchronize from target to source or even from source to target. Additionally, the database is a very complicated world and there are extensive options to configure various database options on the next screen. We also have the option to either generate script or directly execute the script to target server. I like to play on the safe side and I generated the script for my synchronization and later on after review I deployed the scripts on the server. Well, my team and we were able to get going from our disaster in less than 10 minutes. There were few people in our team were indeed disappointed as they were thinking of going home early that day but in less than 10 minutes they had to get back to work. There are so many other features in  dbForge Data Compare for SQL Server, I am already planning to make this product company wide recommended product for Data Compare tool. Hats off to the team who have build this product. Here are few of the features salient features of the dbForge Data Compare for SQL Server Perform SQL Server database comparison to detect changes Compare SQL Server backups with live databases Analyze data differences between two databases Synchronize two databases that went out of sync Restore data of a particular table from the backup Generate data comparison reports in Excel and HTML formats Copy look-up data from development database to production Automate routine data synchronization tasks with command-line interface Go Ahead and Download the dbForge Data Compare for SQL Server right away. It is always a good idea to get familiar with the important tools before hand instead of learning it under pressure of disaster. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Utility, T SQL, Technology

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• OpenWorld: Spotlight on Fusion CRM

  - by Tony Berk

  Oracle OpenWorld is less than 2 weeks away, so you need to start figuring out how you are going to maximize your week. I don't want to discourage you, but I'm pretty sure it is impossible to attend all 2000+ sessions. So you need to focus on what's important to you. Many of our CRM customers will be interested in Fusion CRM, since they have already started Fusion implementations or determining when to start. If that's you, or you are just looking for an overview of Fusion CRM, we've got you covered! Let's start at the top! For an overview of what is in Fusion CRM and where it is going, you should attend the general session and roadmap session: General Session: Oracle Fusion CRM—Improving Sales Effectiveness, Efficiency, and Ease of Use (Session ID: GEN9674) - Oct 2, 11:45 AM. Anthony Lye, Senior VP, Oracle leads this general session focused on Oracle Fusion CRM. Oracle Fusion CRM optimizes territories, combines quota management and incentive compensation, integrates sales and marketing, and cleanses and enriches data—all within a single application platform. Oracle Fusion can be configured, changed, and extended at runtime by end users, business managers, IT, and developers. Oracle Fusion CRM can be used from the Web, from a smartphone, from Microsoft Outlook, or from an iPad. Deloitte, sponsor of the CRM Track, will also present key concepts on CRM implementations. Oracle Fusion Customer Relationship Management: Overview/Strategy/Customer Experiences/Roadmap (CON9407) - Oct 1, 3:15PM. In this session, learn how Oracle Fusion CRM enables companies to create better sales plans, generate more quality leads, and achieve higher win rates and find out why customers are adopting Oracle Fusion CRM. Gain a deeper understanding of the unique capabilities only Oracle Fusion CRM provides, and learn how Oracle’s commitment to CRM innovation is driving a wide range of future enhancements. There is also a General Session for all Fusion Applications providing insight into the current strategy of the full product line and a high-level roadmap for each product area: Oracle Fusion Applications—Overview, Strategy, and Roadmap (GEN9433) - Oct 1, 10:45AM. This session will be repeated on Oct 3, 10:15AM. Now, if you want to drill down into some more detail, there are a lot more sessions with Oracle product management and customers. I'll highlight a few, but suggest you review the Fusion CRM Focus On document, or the search in the Content Catalog or Session Builder.  Driving Sales Performance with Oracle Fusion CRM (CON9744) - Oct 3, 10:15AM. Demonstrates how sales executives can gain instant visibility into their business, deliver pervasive coaching to their reps, maximize their sales pipeline, and drive team alignment. The result is increased sales performance that enables sales executives to deliver more revenue without increasing their resources or expenses. Maximize Your Revenue Potential with Oracle Fusion CRM Sales Planning (CON9751) - Oct 2, 1:15PM. Learn how Oracle Fusion CRM helps companies intelligently optimize sales planning and manage sales performance including the ability to predict their future sales opportunities and use those predictions in conjunction with past sales data to optimally define their sales territories, sales quotas, and incentive compensation plans. Boost Marketing’s Contribution to Revenue with Oracle Fusion CRM Marketing (CON9746) - Oct 3, 11:45AM. Learn how Oracle Fusion CRM can help your organization integrate sales and marketing, using one CRM platform. See how Oracle Fusion CRM can help your organization learn where to invest its precious marketing dollars; drive more revenue with cross-channel marketing and prospecting capabilities, including and not limited to e-mail, Web, and social media; improve lead conversion with integrated lead management functionality; and do more with less by automating many manual tasks. Oracle Fusion CRM: Social Marketing (CON11559) - Oct 1, 3:15PM. Learn how Oracle’s acquisition of Collective Intellect, Vitrue, and Involver extends Oracle Fusion Marketing as a world-class social marketing solution. Oracle Fusion Social CRM Strategy and Roadmap: Future of Collaboration and Social Engagement (CON9750) - Oct 4, 11:15AM. Hear how Oracle can help you know your customers better, encourage brand affinity, and improve collaboration within your ecosystem. This session reviews Oracle's social media solution and shows how you can discover hidden insights buried in your enterprise and social data. Also learn how Oracle Social Network revolutionizes how enterprise users work, collaborate, and share to achieve successful outcomes. Of course, we recommend you hear from the current Fusion CRM customers too. So, don't miss Oracle Fusion Customer Relationship Management: Customer Adoption and Experiences (CON9415) on Oct 3 at 10:15AM for panel of customers discussing implementation experiences, best practices and benefits.  After listening to all of this great information, you are probably going to have questions. Well, the experts will be on hand to help answer your questions and plan how your organization can get going with Fusion CRM. Be sure to head down to the DEMOgrounds and CRM Pavilion in the Moscone West Exhibit Hall. And finally, there is the always popular Meet the Experts session focused on Fusion CRM (MTE9658) on Oct 2 at 5PM (pre-registration via Schedule Builder is recommended.) In addition, there are more sessions on Mobility, Extensibility, Incentive Compensation, Fusion Customer Hub and other key components of the Fusion Applications infrastructure, Oracle Cloud and much, much more! For a full list, utilize the Fusion CRM Focus On document and Content Catalog. Enjoy!

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• 2d tank movement and turret solution

  - by Phil

  Hi! I'm making a simple top-down tank game on the ipad where the user controls the movement of the tank with the left "joystick" and the rotation of the turret with the right one. I've spent several hours just trying to get it to work decently but now I turn to the pros :) I have two referencial objects, one for the movement and one for the rotation. The referencial objects always stay max two units away from the tank and I use them to tell the tank in what direction to move. I chose this approach to decouple movement and rotational behaviour from the raw input of the joysticks, I believe this will make it simpler to implement whatever behaviour I want for the tank. My problem is 1; the turret rotates the long way to the target. With this I mean that the target can be -5 degrees away in rotation and still it rotates 355 degrees instead of -5 degrees. I can't figure out why. The other problem is with the movement. It just doesn't feel right to have the tank turn while moving. I'd like to have a solution that would work as well for the AI as for the player. A blackbox function for the movement where the player only specifies in what direction it should move and it moves there under the constraints that are imposed on it. I am using the standard joystick class found in the Unity iPhone package. This is the code I'm using for the movement: public class TankFollow : MonoBehaviour { //Check angle difference and turn accordingly public GameObject followPoint; public float speed; public float turningSpeed; void Update() { transform.position = Vector3.Slerp(transform.position, followPoint.transform.position, speed * Time.deltaTime); //Calculate angle var forwardA = transform.forward; var forwardB = (followPoint.transform.position - transform.position); var angleA = Mathf.Atan2(forwardA.x, forwardA.z) * Mathf.Rad2Deg; var angleB = Mathf.Atan2(forwardB.x, forwardB.z) * Mathf.Rad2Deg; var angleDiff = Mathf.DeltaAngle(angleA, angleB); //print(angleDiff.ToString()); if (angleDiff > 5) { //Rotate to transform.Rotate(new Vector3(0, (-turningSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else if (angleDiff < 5) { transform.Rotate(new Vector3(0, (turningSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else { } transform.position = new Vector3(transform.position.x, 0, transform.position.z); } } And this is the code I'm using to rotate the turret: void LookAt() { var forwardA = -transform.right; var forwardB = (toLookAt.transform.position - transform.position); var angleA = Mathf.Atan2(forwardA.x, forwardA.z) * Mathf.Rad2Deg; var angleB = Mathf.Atan2(forwardB.x, forwardB.z) * Mathf.Rad2Deg; var angleDiff = Mathf.DeltaAngle(angleA, angleB); //print(angleDiff.ToString()); if (angleDiff - 180 > 1) { //Rotate to transform.Rotate(new Vector3(0, (turretSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); } else if (angleDiff - 180 < -1) { transform.Rotate(new Vector3(0, (-turretSpeed * Time.deltaTime),0)); //transform.rotation = new Quaternion(transform.rotation.x, transform.rotation.y + adjustment, transform.rotation.z, transform.rotation.w); print((angleDiff - 180).ToString()); } else { } } Since I want the turret reference point to turn in relation to the tank (when you rotate the body, the turret should follow and not stay locked on since it makes it impossible to control when you've got two thumbs to work with), I've made the TurretFollowPoint a child of the Turret object, which in turn is a child of the body. I'm thinking that I'm making it too difficult for myself with the reference points but I'm imagining that it's a good idea. Please be honest about this point. So I'll be grateful for any help I can get! I'm using Unity3d iPhone. Thanks!

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• User is trying to leave! Set at-least confirm alert on browser(tab) close event!!

  - by kaushalparik27

  This is something that might be annoying or irritating for end user. Obviously, It's impossible to prevent end user from closing the/any browser. Just think of this if it becomes possible!!!. That will be a horrible web world where everytime you will be attacked by sites and they will not allow to close your browser until you confirm your shopping cart and do the payment. LOL:) You need to open the task manager and might have to kill the running browser exe processes.Anyways; Jokes apart, but I have one situation where I need to alert/confirm from the user in any anyway when they try to close the browser or change the url. Think of this: You are creating a single page intranet asp.net application where your employee can enter/select their TDS/Investment Declarations and you wish to at-least ALERT/CONFIRM them if they are attempting to:[1] Close the Browser[2] Close the Browser Tab[3] Attempt to go some other site by Changing the urlwithout completing/freezing their declaration.So, Finally requirement is clear. I need to alert/confirm the user what he is going to do on above bulleted events. I am going to use window.onbeforeunload event to set the javascript confirm alert box to appear.    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }    </script>See! you are halfway done!. So, every time browser unloads the page, above confirm alert causes to appear on front of user like below:By saying here "every time browser unloads the page"; I mean to say that whenever page loads or postback happens the browser onbeforeunload event will be executed. So, event a button submit or a link submit which causes page to postback would tend to execute the browser onbeforeunload event to fire!So, now the hurdle is how can we prevent the alert "Not to show when page is being postback" via any button/link submit? Answer is JQuery :)Idea is, you just need to set the script reference src to jQuery library and Set the window.onbeforeunload event to null when any input/link causes a page to postback.Below will be the complete code:<head runat="server">    <title></title>    <script src="jquery.min.js" type="text/javascript"></script>    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }        $(function() {            $("a").click(function() {                window.onbeforeunload = null;            });            $("input").click(function() {                window.onbeforeunload = null;            });        });    </script></head><body>    <form id="form1" runat="server">    <div></div>    </form></body></html>So, By this post I have tried to set the confirm alert if user try to close the browser/tab or try leave the site by changing the url. I have attached a working example with this post here. I hope someone might find it helpful.

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• Towards an F# .NET Reflector add-in

  - by CliveT

  When I had the opportunity to spent some time during Red Gate's recent "down tools" week on a project of my choice, the obvious project was an F# add-in for Reflector . To be honest, this was a bit of a misnomer as the amount of time in the designated week for coding was really less than three days, so it was always unlikely that very much progress would be made in such a small amount of time (and that certainly proved to be the case), but I did learn some things from the experiment. Like lots of problems, one useful technique is to take examples, get them to work, and then generalise to get something that works across the board. Unfortunately, I didn't have enough time to do the last stage. The obvious first step is to take a few function definitions, starting with the obvious hello world, moving on to a non-recursive function and finishing with the ubiquitous recursive Fibonacci function. let rec printMessage message  =     printfn  message let foo x  =    (x + 1) let rec fib x  =     if (x >= 2) then (fib (x - 1) + fib (x - 2)) else 1 The major problem in decompiling these simple functions is that Reflector has an in-memory object model that is designed to support object-oriented languages. In particular it has a return statement that allows function bodies to finish early. I used some of the in-built functionality to take the IL and produce an in-memory object model for the language, but then needed to write a transformer to push the return statements to the top of the tree to make it easy to render the code into a functional language. This tree transform works in some scenarios, but not in others where we simply regenerate code that looks more like CPS style. The next thing to get working was library level bindings of values where these values are calculated at runtime. let x = [1 ; 2 ; 3 ; 4] let y = List.map  (fun x -> foo x) x The way that this is translated into a set of classes for the underlying platform means that the code needs to follow references around, from the property exposing the calculated value to the class in which the code for generating the value is embedded. One of the strongest selling points of functional languages is the algebraic datatypes, which allow definitions via standard mathematical-style inductive definitions across the union cases. type Foo =     | Something of int     | Nothing type 'a Foo2 =     | Something2 of 'a     | Nothing2 Such a definition is compiled into a number of classes for the cases of the union, which all inherit from a class representing the type itself. It wasn't too hard to get such a de-compilation happening in the cases I tried. What did I learn from this? Firstly, that there are various bits of functionality inside Reflector that it would be useful for us to allow add-in writers to access. In particular, there are various implementations of the Visitor pattern which implement algorithms such as calculating the number of references for particular variables, and which perform various substitutions which could be more generally useful to add-in writers. I hope to do something about this at some point in the future. Secondly, when you transform a functional language into something that runs on top of an object-based platform, you lose some fidelity in the representation. The F# compiler leaves attributes in place so that tools can tell which classes represent classes from the source program and which are there for purposes of the implementation, allowing the decompiler to regenerate these constructs again. However, decompilation technology is a long way from being able to take unannotated IL and transform it into a program in a different language. For a simple function definition, like Fibonacci, I could write a simple static function and have it come out in F# as the same function, but it would be practically impossible to take a mass of class definitions and have a decompiler translate it automatically into an F# algebraic data type. What have we got out of this? Some data on the feasibility of implementing an F# decompiler inside Reflector, though it's hard at the moment to say how long this would take to do. The work we did is included the 6.5 EAP for Reflector that you can get from the EAP forum. All things considered though, it was a useful way to gain more familiarity with the process of writing an add-in and understand difficulties other add-in authors might experience. If you'd like to check out a video of Down Tools Week, click here.

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• Patch an Existing NK.BIN

  - by Kate Moss' Open Space

  As you know, we can use MAKEIMG.EXE tool to create OS Image file, NK.BIN, or ROMIMAGE.EXE with a BIB for more accurate. But what if the image file is already created but need to be patched or you want to extract a file from NK.BIN? The Platform Builder provide many useful command line utilities, and today I am going to introduce one, BINMOD.EXE. http://msdn.microsoft.com/en-us/library/ee504622.aspx is the official page for BINMOD tool. As the page says, The BinMod Tool (binmod.exe) extracts files from a run-time image, and replaces files in a run-time image and its usage binmod [-i imagename] [-r replacement_filename.ext | -e extraction_filename.ext] This is a simple tool and is easy to use, if we want to extract a file from nk.bin, just type binmod –i nk.bin –e filename.ext And that's it! Or use can try -r command to replace a file inside NK.BIN. The small tool is good but there is a limitation; due to the files in MODULES section are fixed up during ROMIMAGE so the original file format is not preserved, therefore extract or replace file in MODULE section will be impossible. So just like this small tool, this post supposed to be end here, right? Nah... It is not that easy. Just try the above example, and you will find, the tool is not work! Double check the file is in FILES section and the NK.BIN is good, but it just quits. Before you throw away this useless toy, we can try to fix it! Yes, the source of this tool is available in your CE6, private\winceos\COREOS\nk\tools\romimage\binmod. As it is a tool run in your Windows so you need to Windows SDK or Visual Studio to build the code. (I am going to save you some time by skipping the detail as building a desktop console mode program is fairly trivial) The cbinmod.cpp is the core logic for this program and follow up the error message we got, it looks like the following code is suspected.   //   // Extra sanity check...   //   if((DWORD)(HIWORD(pTOCLoc->dllfirst) << 16) <= pTOCLoc->dlllast &&       (DWORD)(LOWORD(pTOCLoc->dllfirst) << 16) <= pTOCLoc->dlllast)   {     dprintf("Found pTOC  = 0x%08x\n", (DWORD)dwpTOC);     fFoundIt = true;     break;   }    else    {     dprintf("NOTICE! Record %d looked like a TOC except DLL first = 0x%08X, and DLL last = 0x%08X\r\n", i, pTOCLoc->dllfirst, pTOCLoc->dlllast);   } The logic checks if dllfirst <= dlllast but look closer, the code only separated the high/low WORD from dllfirst but does not apply the same to dlllast, is that on purpose or a bug? While the TOC is created by ROMIMAGE.EXE, so let's move to ROMIMAGE. In private\winceos\coreos\nk\tools\romimage\romimage\bin.cpp    Module::s_romhdr.dllfirst  = (HIWORD(xip_mem->dll_data_bottom) << 16) | HIWORD(xip_mem->kernel_dll_bottom);   Module::s_romhdr.dlllast   = (HIWORD(xip_mem->dll_data_top) << 16)    | HIWORD(xip_mem->kernel_dll_top); It is clear now, the high word of dll first is the upper 16 bits of XIP DLL bottom and the low word is the upper 16 bits of kernel dll bottom; also, the high word of dll last is the upper 16 bits of XIP DLL top and the low word is the upper 16 bits of kernel dll top. Obviously, the correct statement should be if((DWORD)(HIWORD(pTOCLoc->dllfirst) << 16) <= (DWORD)(HIWORD(pTOCLoc->dlllast) << 16) &&    (DWORD)(LOWORD(pTOCLoc->dllfirst) << 16) <= (DWORD)(LOWORD(pTOCLoc->dlllast) << 16)) So update the code like this should fix this issue or just like the comment, it is an extra sanity check, you can just get rid of it, either way can make the code moving forward and everything worked as advertised.  "Extracting out copies of files from the nk.bin... replacing files... etc." Since the NK.BIN can be compressed, so the BinMod needs the compress.dll to decompress the data, the DLL can be found in C:\program files\microsoft platform builder\6.00\cepb\idevs\imgutils.

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• How to install iodbc in Ubuntu 12.10

  - by Hanynowsky

  I need to install the library iodbc (depends on libodbc2) in my Quantal machine. Yet there is creepy dependency problem. This was replaced somehow by unixodbc which I don't have, installed. Here is what I get when I try to install : sudo apt-get install libiodbc2-dev Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: libiodbc2-dev : Depends: libiodbc2 (= 3.52.7-2build2) but it is not going to be installed Depends: iodbc (= 3.52.7-2build2) but it is not going to be installed E: Unable to correct problems, you have held broken packages. I can tell that iodbc conflicts with odbcinst. Yet, I cannot remove it due to the following: sudo apt-get remove odbcinst Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: akonadi-backend-mysql calligra-l10n-engb kde-l10n-engb kdevelop-l10n kdevelop-php-docs-l10n kdevelop-php-l10n libakonadi-kabc4 libakonadi-notes4 libakonadiprotocolinternals1 libboost-thread1.49.0 libdmtx0a libgpgme++2 libkcalcore4 libkdgantt2 libkholidays4 libkimap4 libkldap4 libkmbox4 libkmime4 libkolabxml0 libkpgp4 libkresources4 libksieve4 libprison0 libqgpgme1 libqrencode3 libxerces-c3.1 Use 'apt-get autoremove' to remove them. The following packages will be REMOVED: akonadi-server k3b k3b-i18n katepart kde-runtime kdelibs-bin kdelibs5-plugins kdepim-runtime kdepim-strigi-plugins kdepimlibs-kio-plugins kdoctools kget kmag kmail kmix kmousetool ksystemlog kubuntu-debug-installer language-pack-kde-ar language-pack-kde-en libakonadi-calendar4 libakonadi-contact4 libakonadi-kcal4 libakonadi-kde4 libakonadi-kmime4 libcalendarsupport4 libincidenceeditorsng4 libk3b6 libkabc4 libkactivities-bin libkactivities6 libkalarmcal2 libkatepartinterfaces4 libkcal4 libkcalutils4 libkcddb4 libkde3support4 libkdepim4 libkdepimdbusinterfaces4 libkdewebkit5 libkemoticons4 libkfile4 libkgapi0 libkhtml5 libkio5 libkleo4 libkmanagesieve4 libkmediaplayer4 libknewstuff3-4 libknotifyconfig4 libkolab0 libkonq-common libkonq5abi1 libkontactinterface4 libkparts4 libkpimidentities4 libkpimtextedit4 libkpimutils4 libkprintutils4 libksieveui4 libktexteditor4 libktnef4 libktorrent4 libkworkspace4abi2 libkxmlrpcclient4 libmailcommon4 libmailimporter4 libmailtransport4 libmessagecomposer4 libmessagecore4 libmessagelist4 libmessageviewer4 libmicroblog4 libnepomuk4 libnepomukcore4abi1 libnepomukquery4a libnepomuksync4 libnepomukutils4 libplasma3 libsoprano4 libtemplateparser4 libvirtodbc0 nepomuk-core odbcinst odbcinst1debian2 plasma-scriptengine-javascript qapt-batch soprano-daemon virtuoso-minimal 0 upgraded, 0 newly installed, 89 to remove and 0 not upgraded. After this operation, 126 MB disk space will be freed. Do you want to continue [Y/n]? Other info: Why do the "iodbc" and "libmyodbc" packages conflict with each other? The root problem is that I need to use a new feature introduced in the latest MySQL Workbench builds (DB Migration) which uses odbc for that matter. Here is what Mysql doc says about it : Linux The Migration Wizard uses iODBC as a driver manager for all of its ODBC connections in Linux. This may give you some troubles because most Linux distributions provide ODBC drivers compiled against unixODBC. This is another driver manager not supported by MySQL Workbench so you won’t be able to use those drivers unless you compile them against iODBC. Here’s what you should do. Make sure that you have iODBC installed. If you are using Debian, Ubuntu or another Debian based distro, type this command in your terminal: $ sudo apt-get install iodbc libiodbc2-dev libpq-dev libssl-dev For RPM based distros (RedHat, Fedora, etc.) type this command instead of the previous one: $ sudo yum install iodbc iodbc-dev libpqxx-devel openssl-devel Now we need to install the PostgreSQL ODBC drivers. Download the psqlODBC source tarball from here. Use the latest version available for download. As of this writing the latest version corresponds to the file psqlodbc-09.01.0200.tar.gz. Extract this tarball to a directory in your hard drive and open a terminal and cd into that directory. Type this in the terminal window: $ ./configure --with-iodbc --enable-pthreads $ make $ sudo make install Verify that you have the file psqlodbcw.so in the /usr/local/lib directory. This package seems to pose the problem probably: dpkg -s odbcinst1debian2 Package: odbcinst1debian2 Status: install ok installed Priority: optional Section: libs Installed-Size: 241 Maintainer: Ubuntu Developers <[email protected]> Architecture: amd64 Multi-Arch: same Source: unixodbc Version: 2.2.14p2-5ubuntu4 Replaces: unixodbc (<< 2.1.1-2) Depends: libc6 (>= 2.14), libltdl7 (>= 2.4.2), odbcinst Pre-Depends: multiarch-support Breaks: libiodbc2, libmyodbc (<< 5.1.6-2), odbc-postgresql (<< 1:09.00.0310-1.1), tdsodbc (<< 0.82-8) Conflicts: odbcinst1, odbcinst1debian1 Description: Support library for accessing odbc ini files This package contains the libodbcinst library from unixodbc, a library used by ODBC drivers for reading their configuration settings from /etc/odbc.ini and ~/.odbc.ini. . Also contained in this package are the driver setup plugins, which describe the features supported by individual ODBC drivers. Homepage: http://www.unixodbc.org/ Original-Maintainer: Steve Langasek <[email protected]> I have no broken packages:

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• IBM "per core" comparisons for SPECjEnterprise2010

  - by jhenning

  I recently stumbled upon a blog entry from Roman Kharkovski (an IBM employee) comparing some SPECjEnterprise2010 results for IBM vs. Oracle. Mr. Kharkovski's blog claims that SPARC delivers half the transactions per core vs. POWER7. Prior to any argument, I should say that my predisposition is to like Mr. Kharkovski, because he says that his blog is intended to be factual; that the intent is to try to avoid marketing hype and FUD tactic; and mostly because he features a picture of himself wearing a bike helmet (me too). Therefore, in a spirit of technical argument, rather than FUD fight, there are a few areas in his comparison that should be discussed. Scaling is not free For any benchmark, if a small system scores 13k using quantity R1 of some resource, and a big system scores 57k using quantity R2 of that resource, then, sure, it's tempting to divide: is  13k/R1 > 57k/R2 ? It is tempting, but not necessarily educational. The problem is that scaling is not free. Building big systems is harder than building small systems. Scoring  13k/R1  on a little system provides no guarantee whatsoever that one can sustain that ratio when attempting to handle more than 4 times as many users. Choosing the denominator radically changes the picture When ratios are used, one can vastly manipulate appearances by the choice of denominator. In this case, lots of choices are available for the resource to be compared (R1 and R2 above). IBM chooses to put cores in the denominator. Mr. Kharkovski provides some reasons for that choice in his blog entry. And yet, it should be noted that the very concept of a core is: arbitrary: not necessarily comparable across vendors; fluid: modern chips shift chip resources in response to load; and invisible: unless you have a microscope, you can't see it. By contrast, one can actually see processor chips with the naked eye, and they are a bit easier to count. If we put chips in the denominator instead of cores, we get: 13161.07 EjOPS / 4 chips = 3290 EjOPS per chip for IBM vs 57422.17 EjOPS / 16 chips = 3588 EjOPS per chip for Oracle The choice of denominator makes all the difference in the appearance. Speaking for myself, dividing by chips just seems to make more sense, because: I can see chips and count them; and I can accurately compare the number of chips in my system to the count in some other vendor's system; and Tthe probability of being able to continue to accurately count them over the next 10 years of microprocessor development seems higher than the probability of being able to accurately and comparably count "cores". SPEC Fair use requirements Speaking as an individual, not speaking for SPEC and not speaking for my employer, I wonder whether Mr. Kharkovski's blog article, taken as a whole, meets the requirements of the SPEC Fair Use rule www.spec.org/fairuse.html section I.D.2. For example, Mr. Kharkovski's footnote (1) begins Results from http://www.spec.org as of 04/04/2013 Oracle SUN SPARC T5-8 449 EjOPS/core SPECjEnterprise2010 (Oracle's WLS best SPECjEnterprise2010 EjOPS/core result on SPARC). IBM Power730 823 EjOPS/core (World Record SPECjEnterprise2010 EJOPS/core result) The questionable tactic, from a Fair Use point of view, is that there is no such metric at the designated location. At www.spec.org, You can find the SPEC metric 57422.17 SPECjEnterprise2010 EjOPS for Oracle and You can also find the SPEC metric 13161.07 SPECjEnterprise2010 EjOPS for IBM. Despite the implication of the footnote, you will not find any mention of 449 nor anything that says 823. SPEC says that you can, under its fair use rule, derive your own values; but it emphasizes: "The context must not give the appearance that SPEC has created or endorsed the derived value." Substantiation and transparency Although SPEC disclaims responsibility for non-SPEC information (section I.E), it says that non-SPEC data and methods should be accurate, should be explained, should be substantiated. Unfortunately, it is difficult or impossible for the reader to independently verify the pricing: Were like units compared to like (e.g. list price to list price)? Were all components (hw, sw, support) included? Were all fees included? Note that when tpc.org shows IBM pricing, there are often items such as "PROCESSOR ACTIVATION" and "MEMORY ACTIVATION". Without the transparency of a detailed breakdown, the pricing claims are questionable. T5 claim for "Fastest Processor" Mr. Kharkovski several times questions Oracle's claim for fastest processor, writing You see, when you publish industry benchmarks, people may actually compare your results to other vendor's results. Well, as we performance people always say, "it depends". If you believe in performance-per-core as the primary way of looking at the world, then yes, the POWER7+ is impressive, spending its chip resources to support up to 32 threads (8 cores x 4 threads). Or, it just might be useful to consider performance-per-chip. Each SPARC T5 chip allows 128 hardware threads to be simultaneously executing (16 cores x 8 threads). The Industry Standard Benchmark that focuses specifically on processor chip performance is SPEC CPU2006. For this very well known and popular benchmark, SPARC T5: provides better performance than both POWER7 and POWER7+, for 1 chip vs. 1 chip, for 8 chip vs. 8 chip, for integer (SPECint_rate2006) and floating point (SPECfp_rate2006), for Peak tuning and for Base tuning. For example, at the 8-chip level, integer throughput (SPECint_rate2006) is: 3750 for SPARC 2170 for POWER7+. You can find the details at the March 2013 BestPerf CPU2006 page SPEC is a trademark of the Standard Performance Evaluation Corporation, www.spec.org. The two specific results quoted for SPECjEnterprise2010 are posted at the URLs linked from the discussion. Results for SPEC CPU2006 were verified at spec.org 1 July 2013, and can be rechecked here.

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• In the Mobile and Tablet World, How Much is Too Much?

  - by andrewbrust

  The week of April 26th was a huge one in the world of mobile and tablet devices,  There were so many individual developments, announcements and solidifications of strategy, it’s almost impossible to believe they occurred in the same month, let alone the same week. Things started with Apple and Gizmodo having a Law and Order moment over the latter’s procurement of what appears to be the former’s 4th gen iPhone prototype.  We found out on the 26th that Gizmodo blogger Jason Chen’s apartment was raided by police and, honestly, that was a bit much. But Apple didn’t stop there.  They also published Steve Job’s critique of Adobe Flash and his explanation of Cupertino’s embargo of Flash on iPhones, iPods and iPads.  If you ask me, this too, was a bit much. Apple finished up the week by releasing the 3G version of its iPad product to the US market. I like (iLike?) my WiFi iPad.  The idea of getting a version of it that required a second 3G service monthly subscription, is, well, a bit  much. Microsoft was in the news too.  It killed a project it hadn’t even acknowledged the existence of: the Courier tablet.  That’s a bit much too.  If a tree falls in the woods, and Microsoft says they can’t hear it anyway, could they really have chopped it down? Maybe Microsoft Research should have licensed some of Courier’s technology from other parts of Microsoft.  Then maybe they could have kept the product alive.  Ask HTC: they’re going to be licensing technology from Microsoft because Redmond insists that Google’s Android operating system infringes on certain of their patents.  And since HTC now builds a number of handsets on Android, instead of being beholden, as they once were, to Windows Mobile, that means they can keep making their products.  Why does HTC have to pay the royalties, and not Google?  Maybe Microsoft decided that going after GOOG would have been a bit much, even for them. The agreement came not a moment to soon: HTC released their “Droid Incredible” (that name’s a bit much), an Android 2.1 handset with amazing hardware and HTC’s own Sense UI, on April 30th (this past Friday). This phone is very well-reviewed.  Maybe that’s why Google basically decided to beg off introducing a version of its Nexus One phone (also manufactured by HTC) on the Verizon Wireless network.  Google backing down?  That’s incredible, if not also a bit much. And that brings us to HP.  Which this week announced its acquisition of Palm and its webOS mobile phone touch-oriented operating system.  HP also killed its own Slate initiative.  Apparently HP realized that Windows 7, even with a proprietary HP touch UI added on top, is no match for the iPad.  I’m guessing they think webOS might work a bit better,  And I’m wondering if HP even wants to use webOS for phone handsets, beyond the Pre and Pixi.  Using it just for slate devices would be a bit extreme, but maybe not too much. Honestly, this was not Microsoft’s best week.  It killed a project and a close partner did likewise.  Then that same partner bought a competing OS product, while another partner released their new product that uses yet another competing OS platform. What did Microsoft actually produce this past week? An update to its Windows Phone 7 developer tools that actually works with the version of Visual Studio 2010 released on April 12th, and the version of Silverlight released three days later. That took three weeks to get synced up, and that’s a bit much too. But at least it happened. Windows Phone 7 is Microsoft’s best hope for a comeback in the SmartPhone market and to offer a credible touch-based tablet device.  This week, two of Microsoft’s slate initiatives died, and its only mobile phone victory was around its competitor’s operating system.  I hope the new platform gets Redmond out of the PC ghetto and into the classes of device that get people really excited today.  If it can’t, that would be a bit much; probably too much.  And, as the signs at the Lonestar Cafe in NYC used to say, too much ain’t enough.

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• Adventures in Scrum: Lesson 1 &ndash; The failed Sprint

  - by Martin Hinshelwood

  I recently had a conversation with a product owner that wanted to have the Scrum team broken up into smaller units so that less time was wasted on the Scrum Ceremonies! Their complaint was around the need in Scrum to have the entire “Team” (7+-2) involved in the sizing of the work during the “Sprint Planning Meeting”.  The standard flippant answer of all Scrum professionals, “Well that's not Scrum”, does not get you any brownie points in these situations. The response could be “Well we are not doing Scrum then” which in turn leads to “We are doing Scrum…But, we have split the scrum team into units of 2/3 so that they can concentrate on a specific area of work”. While this may work, it is not Scrum and should not be called so… It is just a form of Agile. Don’t get me wrong at this stage, there is nothing wrong with Agile, just don’t call it Scrum. The reason that the Product Owner wants to do this is that, in effect, through a number of miscommunications and failings in our implementation of Scrum, there was NO unit of potentially Shippable software at the end of the first sprint. It does not matter to them that most Scrum teams will fail the first Sprint, even those that are high performing teams. Remember it is the product owners their money! We should NOT break up scrum teams into smaller units for the purpose of having less people tied up in the Scrum Ceremonies. The amount of backlog the Team selects is solely up to the Team… Only the Team can assess what it can accomplish over the upcoming Sprint. - Scrum Guide, Scrum.org The entire team must accept the work and in order to understand what they can accept they must be free to size it as a team. This both encourages common understanding and increases visibility on why team members think a task is of a particular size. This has the benefit of increasing the knowledge of the entire team in the problem domain. A new Team often first realizes that it will either sink or swim as a Team, not individually, in this meeting. The Team realizes that it must rely on itself. As it realizes this, it starts to self-organize to take on the characteristics and behaviour of a real Team. - Scrum Guide, Scrum.org This paragraph goes to the why of having the whole team at the meeting; The goal of Scrum it to produce a unit of potentially shippable software at the end of every Sprint. In order to achieve this we need high performing teams and this is what Scrum as a framework has been optimised to produce. I think that our Product Owner is understandably upset over loosing two weeks work and is losing sight the end goal of Scrum in the failures of the moment. As the man spending the money, I completely understand his perspective and I think that we should not have started Scrum on an internal project, but selected a customer  that is open to the ideas and complications of Scrum. So, what should we have NOT done on our first Scrum project: Should not have had 3 interns as the only on site resource – This lead to bad practices as the experienced guys were not there helping and correcting as they usually would. Should not have had the only experienced guys offsite – With both the experienced technical guys in completely different time zones it was difficult to get time for questions. Helping the guys on site was just plain impossible. Should not have used a part time ScrumMaster – Although the ScrumMaster attended all of the Ceremonies, because they are only in 2 full days of the week it makes it difficult for the team to raise impediments as they go. Should not have used a proxy product owner. – This was probably the worst decision that was made. Mainly because the proxy product owner did not have the same vision as the product owner. While Scrum does not explicitly reject the idea of a Proxy Product Owner, I do not think it works very well in practice. The “single wringable neck” needs to contain both the Money and the Vision as well as attending the required meetings. I will be brining all of these things up at the Sprint Retrospective and we will learn from our mistakes and move on. Do, Inspect then Adapt…   Technorati Tags: Scrum,Sprint Planing,Sprint Retrospective,Scrum.org,Scrum Guide,Scrum Ceremonies,Scrummaster,Product Owner Need Help? Professional Scrum Developer Training SSW has six Professional Scrum Developer Trainers who specialise in training your developers in implementing Scrum with Microsoft's Visual Studio ALM tools.

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• Master Data Management Implementation Styles

  - by david.butler(at)oracle.com

  In any Master Data Management solution deployment, one of the key decisions to be made is the choice of the MDM architecture. Gartner and other analysts describe some different Hub deployment styles, which must be supported by a best of breed MDM solution in order to guarantee the success of the deployment project.   Registry Style: In a Registry Style MDM Hub, the various source systems publish their data and a subscribing Hub stores only the source system IDs, the Foreign Keys (record IDs on source systems) and the key data values needed for matching. The Hub runs the cleansing and matching algorithms and assigns unique global identifiers to the matched records, but does not send any data back to the source systems. The Registry Style MDM Hub uses data federation capabilities to build the "virtual" golden view of the master entity from the connected systems.   Consolidation Style: The Consolidation Style MDM Hub has a physically instantiated, "golden" record stored in the central Hub. The authoring of the data remains distributed across the spoke systems and the master data can be updated based on events, but is not guaranteed to be up to date. The master data in this case is usually not used for transactions, but rather supports reporting; however, it can also be used for reference operationally.   Coexistence Style: The Coexistence Style MDM Hub involves master data that's authored and stored in numerous spoke systems, but includes a physically instantiated golden record in the central Hub and harmonized master data across the application portfolio. The golden record is constructed in the same manner as in the consolidation style, and, in the operational world, Consolidation Style MDM Hubs often evolve into the Coexistence Style. The key difference is that in this architectural style the master data stored in the central MDM system is selectively published out to the subscribing spoke systems.   Transaction Style: In this architecture, the Hub stores, enhances and maintains all the relevant (master) data attributes. It becomes the authoritative source of truth and publishes this valuable information back to the respective source systems. The Hub publishes and writes back the various data elements to the source systems after the linking, cleansing, matching and enriching algorithms have done their work. Upstream, transactional applications can read master data from the MDM Hub, and, potentially, all spoke systems subscribe to updates published from the central system in a form of harmonization. The Hub needs to support merging of master records. Security and visibility policies at the data attribute level need to be supported by the Transaction Style hub, as well.   Adaptive Transaction Style: This is similar to the Transaction Style, but additionally provides the capability to respond to diverse information and process requests across the enterprise. This style emerged most recently to address the limitations of the above approaches. With the Adaptive Transaction Style, the Hub is built as a platform for consolidating data from disparate third party and internal sources and for serving unified master entity views to operational applications, analytical systems or both. This approach delivers a real-time Hub that has a reliable, persistent foundation of master reference and relationship data, along with all the history and lineage of data changes needed for audit and compliance tracking. On top of this persistent master data foundation, the Hub can dynamically aggregate transaction data on demand from different source systems to deliver the unified golden view to downstream systems. Data can also be accessed through batch interfaces, published to a message bus or served through a real-time services layer. New data sources can be readily added in this approach by extending the data model and by configuring the new source mappings and the survivorship rules, meaning that all legacy data hubs can be leveraged to contribute their records/rules into the new transaction hub. Finally, through rich user interfaces for data stewardship, it allows exception handling by business analysts to keep it current with business rules/practices while maintaining the reliability of best-of-breed master records.   Confederation Style: In this architectural style, several Hubs are maintained at departmental and/or agency and/or territorial level, and each of them are connected to the other Hubs either directly or via a central Super-Hub. Each Domain level Hub can be implemented using any of the previously described styles, but normally the Central Super-Hub is a Registry Style one. This is particularly important for Public Sector organizations, where most of the time it is practically or legally impossible to store in a single central hub all the relevant constituent information from all departments.   Oracle MDM Solutions can be deployed according to any of the above MDM architectural styles, and have been specifically designed to fully support the Transaction and Adaptive Transaction styles. Oracle MDM Solutions provide strong data federation and integration capabilities which are key to enabling the use of the Confederated Hub as a possible architectural style approach. Don't lock yourself into a solution that cannot evolve with your needs. With Oracle's support for any type of deployment architecture, its ability to leverage the outstanding capabilities of the Oracle technology stack, and its open interfaces for non-Oracle technology stacks, Oracle MDM Solutions provide a low TCO and a quick ROI by enabling a phased implementation strategy.

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• Breaking through the class sealing

  - by Jason Crease

  Do you understand 'sealing' in C#?  Somewhat?  Anyway, here's the lowdown. I've done this article from a C# perspective, but I've occasionally referenced .NET when appropriate. What is sealing a class? By sealing a class in C#, you ensure that you ensure that no class can be derived from that class.  You do this by simply adding the word 'sealed' to a class definition: public sealed class Dog {} Now writing something like " public sealed class Hamster: Dog {} " you'll get a compile error like this: 'Hamster: cannot derive from sealed type 'Dog' If you look in an IL disassembler, you'll see a definition like this: .class public auto ansi sealed beforefieldinit Dog extends [mscorlib]System.Object Note the addition of the word 'sealed'. What about sealing methods? You can also seal overriding methods.  By adding the word 'sealed', you ensure that the method cannot be overridden in a derived class.  Consider the following code: public class Dog : Mammal { public sealed override void Go() { } } public class Mammal { public virtual void Go() { } } In this code, the method 'Go' in Dog is sealed.  It cannot be overridden in a subclass.  Writing this would cause a compile error: public class Dachshund : Dog { public override void Go() { } } However, we can 'new' a method with the same name.  This is essentially a new method; distinct from the 'Go' in the subclass: public class Terrier : Dog { public new void Go() { } } Sealing properties? You can also seal seal properties.  You add 'sealed' to the property definition, like so: public sealed override string Name {     get { return m_Name; }     set { m_Name = value; } } In C#, you can only seal a property, not the underlying setters/getters.  This is because C# offers no override syntax for setters or getters.  However, in underlying IL you seal the setter and getter methods individually - a property is just metadata. Why bother sealing? There are a few traditional reasons to seal: Invariance. Other people may want to derive from your class, even though your implementation may make successful derivation near-impossible.  There may be twisted, hacky logic that could never be second-guessed by another developer.  By sealing your class, you're protecting them from wasting their time.  The CLR team has sealed most of the framework classes, and I assume they did this for this reason. Security.  By deriving from your type, an attacker may gain access to functionality that enables him to hack your system.  I consider this a very weak security precaution. Speed.  If a class is sealed, then .NET doesn't need to consult the virtual-function-call table to find the actual type, since it knows that no derived type can exist.  Therefore, it could emit a 'call' instead of 'callvirt' or at least optimise the machine code, thus producing a performance benefit.  But I've done trials, and have been unable to demonstrate this If you have an example, please share! All in all, I'm not convinced that sealing is interesting or important.  Anyway, moving-on... What is automatically sealed? Value types and structs.  If they were not always sealed, all sorts of things would go wrong.  For instance, structs are laid-out inline within a class.  But what if you assigned a substruct to a struct field of that class?  There may be too many fields to fit. Static classes.  Static classes exist in C# but not .NET.  The C# compiler compiles a static class into an 'abstract sealed' class.  So static classes are already sealed in C#. Enumerations.  The CLR does not track the types of enumerations - it treats them as simple value types.  Hence, polymorphism would not work. What cannot be sealed? Interfaces.  Interfaces exist to be implemented, so sealing to prevent implementation is dumb.  But what if you could prevent interfaces from being extended (i.e. ban declarations like "public interface IMyInterface : ISealedInterface")?  There is no good reason to seal an interface like this.  Sealing finalizes behaviour, but interfaces have no intrinsic behaviour to finalize Abstract classes.  In IL you can create an abstract sealed class.  But C# syntax for this already exists - declaring a class as a 'static', so it forces you to declare it as such. Non-override methods.  If a method isn't declared as override it cannot be overridden, so sealing would make no difference.  Note this is stated from a C# perspective - the words are opposite in IL.  In IL, you have four choices in total: no declaration (which actually seals the method), 'virtual' (called 'override' in C#), 'sealed virtual' ('sealed override' in C#) and 'newslot virtual' ('new virtual' or 'virtual' in C#, depending on whether the method already exists in a base class). Methods that implement interface methods.  Methods that implement an interface method must be virtual, so cannot be sealed. Fields.  A field cannot be overridden, only hidden (using the 'new' keyword in C#), so sealing would make no sense.

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• Death March

  - by Nick Harrison

  It is a horrible sight to watch a project fail. There are few things as bad. Watching a project fail regardless of the reason is almost like sitting in a room with a "Dementor" from Harry Potter. It will literally suck all of the life and joy out of the room. Nearly every project that I have seen fail has failed because of political challenges or management challenges. Sometimes there are technical challenges that bring a project to its knees, but usually projects fail for less technical reasons. Here a few observations about projects failing for political reasons. Both the client and the consultants have to be committed to seeing the project succeed. Put simply, you cannot solve a problem when the primary stake holders do not truly want it solved. This could come from a consultant being more interested in extended the engagement. It could come from a client being afraid of what will happen to them once the problem is solved. It could come from disenfranchised stake holders. Sometimes a project is beset on all sides. When you find yourself working on a project that has this kind of threat, do all that you can to constrain the disruptive influences of the bad apples. If their influence cannot be constrained, you truly have no choice but to move on to a new project. Tough choices have to be made to make a project successful. These choices will affect everyone involved in the project. These choices may involve users not getting a change request through that they want. Developers may not get to use the tools that they want. Everyone may have to put in more hours that they originally planned. Steps may be skipped. Compromises will be made, but if everyone stays committed to the end goal, you can still be successful. If individuals start feeling disgruntled or resentful of the compromises reached, the project can easily be derailed. When everyone is not working towards a common goal, it is like driving with one foot on the break and one foot on the accelerator. Not only will you not get to where you are planning, you will also damage the car and possibly the passengers as well.   It is important to always keep the end result in mind. Regardless of the development methodology being followed, the end goal is not comprehensive documentation. In all cases, it is working software. Comprehensive documentation is nice but useless if the software doesn't work.   You can never get so distracted by the next goal that you fail to meet the current goal. Most projects are ultimately marathons. This means that the pace must be sustainable. Regardless of the temptations, you cannot burn the team alive. Processes will fail. Technology will get outdated. Requirements will change, but your people will adapt and learn and grow. If everyone on the team from the most senior analyst to the most junior recruit trusts and respects each other, there is no challenge that they cannot overcome. When everyone involved faces challenges with the attitude "This is my project and I will not let it fail" "You are my teammate and I will not let you fail", you will in fact not fail. When you find a team that embraces this attitude, protect it at all cost. Edward Yourdon wrote a book called Death March. In it, he included a graph for categorizing Death March project types based on the Happiness of the Team and the Chances of Success.   Chances are we have all worked on Death March projects. We will all most likely work on more Death March projects in the future. To a certain extent, they seem to be inevitable, but they should never be suicide or ugly. Ideally, they can all be "Mission Impossible" where everyone works hard, has fun, and knows that there is good chance that they will succeed. If you are ever lucky enough to work on such a project, you will know that sense of pride that comes from the eventual success. You will recognize a profound bond with the team that you worked with. Chances are it will change your life or at least your outlook on life. If you have not already read this book, get a copy and study it closely. It will help you survive and make the most out of your next Death March project.

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• My Red Gate Experience

  - by Colin Rothwell

  I’m Colin, and I’ve been an intern working with Mike in publishing on Simple-Talk and SQLServerCentral for the past ten weeks. I’ve mostly been working “behind the scenes”, making improvements to the spam filtering, along with various other small tweaks. When I arrived at Red Gate, one of the first things Mike asked me was what I wanted to get out of the internship. It wasn’t a question I’d given a great deal of thought to, but my immediate response was the same as almost anybody: to support my growing family. Well, ok, not quite that, but money was certainly a motivator, along with simply making sure that I didn’t get bored over the summer. Three months is a long time to fill, and many of my friends end up getting bored, or worse, knitting obsessively. With the arrogance which seems fairly common among Cambridge people, I wasn’t expecting to really learn much here! In my mind, the part of the year where I am at Uni is the part where I learn things, whilst Red Gate would be an opportunity to apply what I’d learnt. Thankfully, the opposite is true: I’ve learnt a lot during my time here, and there has been a definite positive impact on the way I write code. The first thing I’ve really learnt is that test-driven development is, in general, a sensible way of working. Before coming, I didn’t really get it: how could you test something you hadn’t yet written? It didn’t make sense! My problem was seeing a test as having to test all the behaviour of a given function. Writing tests which test the bare minimum possible and building them up is a really good way of crystallising the direction the code needs to grow in, and ensures you never attempt to write too much code at time. One really good experience of this was early on in my internship when Mike and I were working on the query used to list active authors: I’d written something which I thought would do the trick, but by starting again using TDD we grew something which revealed that there were several subtle mistakes in the query I’d written. I’ve also been awakened to the value of pair programming. Whilst I could sort of see the point before coming, I also thought that it was impossible that two people would ever get more done at the same computer than if they were working separately. I still think that this is true for projects with pieces that developers can easily work on independently, and with developers who both know the codebase, but I’ve found that pair programming can be really good for learning a code base, and for building up small projects to the point where you can start working on separate components, as well as solving particularly difficult problems. Later on in my internship, for my down tools week project, I was working on adding Python support to Glimpse. Another intern and I we pair programmed the entire project, using ping pong pair programming as much as possible. One bonus that this brought which I wasn’t expecting was that I found myself less prone to distraction: with someone else peering over my shoulder, I didn’t have the ever-present temptation to open gmail, or facebook, or yammer, or twitter, or hacker news, or reddit, and so on, and so forth. I’m quite proud of this project: I think it’s some of the best code I’ve written. I’ve also been really won over to the value of descriptive variables names. In my pre-Red Gate life, as a lone-ranger style cowboy programmer, I’d developed a tendency towards laziness in variable names, sometimes abbreviating or, worse, using acronyms. I’ve swiftly realised that this is a bad idea when working with a team: saving a few key strokes is inevitably not worth it when it comes to reading code again in the future. Longer names also mean you can do away with a majority of comments. I appreciate that if you’ve come up with an O(n*log n) algorithm for something which seemed O(n^2), you probably want to explain how it works, but explaining what a variable name means is a big no no: it’s so very easy to change the behaviour of the code, whilst forgetting about the comments. Whilst at Red Gate, I took the opportunity to attend a code retreat, which really helped me to solidify all the things I’d learnt. To be completely free of any existing code base really lets you focus on best practises and think about how you write code. If you get a chance to go on a similar event, I’d highly recommend it! Cycling to Red Gate, I’ve also become much better at fitting inner tubes: if you’re struggling to get the tube out, or re-fit the tire, letting a bit of air out usually helps. I’ve also become quite a bit better at foosball and will miss having a foosball table! I’d like to finish off by saying thank you to everyone at Red Gate for having me. I’ve really enjoyed working with, and learning from, the team that brings you this web site. If you meet any of them, buy them a drink!

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• Design Pattern for Complex Data Modeling

  - by Aaron Hayman

  I'm developing a program that has a SQL database as a backing store. As a very broad description, the program itself allows a user to generate records in any number of user-defined tables and make connections between them. As for specs: Any record generated must be able to be connected to any other record in any other user table (excluding itself...the record, not the table). These "connections" are directional, and the list of connections a record has is user ordered. Moreover, a record must "know" of connections made from it to others as well as connections made to it from others. The connections are kind of the point of this program, so there is a strong possibility that the number of connections made is very high, especially if the user is using the software as intended. A record's field can also include aggregate information from it's connections (like obtaining average, sum, etc) that must be updated on change from another record it's connected to. To conserve memory, only relevant information must be loaded at any one time (can't load the entire database in memory at load and go from there). I cannot assume the backing store is local. Right now it is, but eventually this program will include syncing to a remote db. Neither the user tables, connections or records are known at design time as they are user generated. I've spent a lot of time trying to figure out how to design the backing store and the object model to best fit these specs. In my first design attempt on this, I had one object managing all a table's records and connections. I attempted this first because it kept the memory footprint smaller (records and connections were simple dicts), but maintaining aggregate and link information between tables became....onerous (ie...a huge spaghettified mess). Tracing dependencies using this method almost became impossible. Instead, I've settled on a distributed graph model where each record and connection is 'aware' of what's around it by managing it own data and connections to other records. Doing this increases my memory footprint but also let me create a faulting system so connections/records aren't loaded into memory until they're needed. It's also much easier to code: trace dependencies, eliminate cycling recursive updates, etc. My biggest problem is storing/loading the connections. I'm not happy with any of my current solutions/ideas so I wanted to ask and see if anybody else has any ideas of how this should be structured. Connections are fairly simple. They contain: fromRecordID, fromTableID, fromRecordOrder, toRecordID, toTableID, toRecordOrder. Here's what I've come up with so far: Store all the connections in one big table. If I do this, either I load all connections at once (one big db call) or make a call every time a user table is loaded. The big issue here: the size of the connections table has the potential to be huge, and I'm afraid it would slow things down. Store in separate tables all the outgoing connections for each user table. This is probably the worst idea I've had. Now my connections are 'spread out' over multiple tables (one for each user table), which means I have to make a separate DB called to each table (or make a huge join) just to find all the incoming connections for a particular user table. I've avoided making "one big ass table", but I'm not sure the cost is worth it. Store in separate tables all outgoing AND incoming connections for each user table (using a flag to distinguish between incoming vs outgoing). This is the idea I'm leaning towards, but it will essentially double the total DB storage for all the connections (as each connection will be stored in two tables). It also means I have to make sure connection information is kept in sync in both places. This is obviously not ideal but it does mean that when I load a user table, I only need to load one 'connection' table and have all the information I need. This also presents a separate problem, that of connection object creation. Since each user table has a list of all connections, there are two opportunities for a connection object to be made. However, connections objects (designed to facilitate communication between records) should only be created once. This means I'll have to devise a common caching/factory object to make sure only one connection object is made per connection. Does anybody have any ideas of a better way to do this? Once I've committed to a particular design pattern I'm pretty much stuck with it, so I want to make sure I've come up with the best one possible.

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• Platformer Starter Kit - Collision Issues

  - by Cyral

  I'm having trouble with my game that is based off the XNA Platformer starter kit. My game uses smaller tiles (16x16) then the original (32x40) which I'm thinking may be having an effect on collision (Being it needs to be more precise). Standing on the edge of a tile and jumping causes the player to move off the the tile when he lands. And 80% of the time, when the player lands, he goes flying though SOLID tiles in a diagonal fashion. This is very annoying as it is almost impossible to test other features, when spawning and jumping will result in the player landing in another part of the level or falling off the edge completely. The code is as follows: /// <summary> /// Updates the player's velocity and position based on input, gravity, etc. /// </summary> public void ApplyPhysics(GameTime gameTime) { float elapsed = (float)gameTime.ElapsedGameTime.TotalSeconds; Vector2 previousPosition = Position; // Base velocity is a combination of horizontal movement control and // acceleration downward due to gravity. velocity.X += movement * MoveAcceleration * elapsed; velocity.Y = MathHelper.Clamp(velocity.Y + GravityAcceleration * elapsed, -MaxFallSpeed, MaxFallSpeed); velocity.Y = DoJump(velocity.Y, gameTime); // Apply pseudo-drag horizontally. if (IsOnGround) velocity.X *= GroundDragFactor; else velocity.X *= AirDragFactor; // Prevent the player from running faster than his top speed. velocity.X = MathHelper.Clamp(velocity.X, -MaxMoveSpeed, MaxMoveSpeed); // Apply velocity. Position += velocity * elapsed; Position = new Vector2((float)Math.Round(Position.X), (float)Math.Round(Position.Y)); // If the player is now colliding with the level, separate them. HandleCollisions(); // If the collision stopped us from moving, reset the velocity to zero. if (Position.X == previousPosition.X) velocity.X = 0; if (Position.Y == previousPosition.Y) velocity.Y = 0; } /// <summary> /// Detects and resolves all collisions between the player and his neighboring /// tiles. When a collision is detected, the player is pushed away along one /// axis to prevent overlapping. There is some special logic for the Y axis to /// handle platforms which behave differently depending on direction of movement. /// </summary> private void HandleCollisions() { // Get the player's bounding rectangle and find neighboring tiles. Rectangle bounds = BoundingRectangle; int leftTile = (int)Math.Floor((float)bounds.Left / Tile.Width); int rightTile = (int)Math.Ceiling(((float)bounds.Right / Tile.Width)) - 1; int topTile = (int)Math.Floor((float)bounds.Top / Tile.Height); int bottomTile = (int)Math.Ceiling(((float)bounds.Bottom / Tile.Height)) - 1; // Reset flag to search for ground collision. isOnGround = false; // For each potentially colliding tile, for (int y = topTile; y <= bottomTile; ++y) { for (int x = leftTile; x <= rightTile; ++x) { // If this tile is collidable, ItemCollision collision = Level.GetCollision(x, y); if (collision != ItemCollision.Passable) { // Determine collision depth (with direction) and magnitude. Rectangle tileBounds = Level.GetBounds(x, y); Vector2 depth = RectangleExtensions.GetIntersectionDepth(bounds, tileBounds); if (depth != Vector2.Zero) { float absDepthX = Math.Abs(depth.X); float absDepthY = Math.Abs(depth.Y); // Resolve the collision along the shallow axis. if (absDepthY < absDepthX || collision == ItemCollision.Platform) { // If we crossed the top of a tile, we are on the ground. if (previousBottom <= tileBounds.Top) isOnGround = true; // Ignore platforms, unless we are on the ground. if (collision == ItemCollision.Impassable || IsOnGround) { // Resolve the collision along the Y axis. Position = new Vector2(Position.X, Position.Y + depth.Y); // Perform further collisions with the new bounds. bounds = BoundingRectangle; } } else if (collision == ItemCollision.Impassable) // Ignore platforms. { // Resolve the collision along the X axis. Position = new Vector2(Position.X + depth.X, Position.Y); // Perform further collisions with the new bounds. bounds = BoundingRectangle; } } } } } // Save the new bounds bottom. previousBottom = bounds.Bottom; } It also tends to jitter a little bit sometimes, I'm solved some of this with some fixes I found here on stackexchange, But Ive only seen one other case of the flying though blocks problem. This question seems to have a similar problem in the video, but mine is more crazy. Again this is a very annoying bug! Any help would be greatly appreciated! EDIT: Speed stuff // Constants for controling horizontal movement private const float MoveAcceleration = 13000.0f; private const float MaxMoveSpeed = 1750.0f; private const float GroundDragFactor = 0.48f; private const float AirDragFactor = 0.58f; // Constants for controlling vertical movement private const float MaxJumpTime = 0.35f; private const float JumpLaunchVelocity = -3500.0f; private const float GravityAcceleration = 3400.0f; private const float MaxFallSpeed = 550.0f; private const float JumpControlPower = 0.14f;

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