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• SO-Aware Service Explorer – Configure and Export your services from VS 2010 into the repository

  - by cibrax

  We have introduced a new Visual Studio tool called “Service Explorer” as part of the new SO-Aware SDK version 1.3 to help developers to configure and export any regular WCF service into the SO-Aware service repository. This new tool is a regular Visual Studio Tool Window that can be opened from “View –> Other Windows –> Services Explorer”. Once you open the Services Explorer, you will able to see all the available WCF services in the Visual Studio Solution. In the image above, you can see that a “HelloWorld” service was found in the solution and listed under the Tool window on the left. There are two things you can do for a new service in tool, you can either export it to SO-Aware repository or associate it to an existing service version in the repository. Exporting the service to SO-Aware means that you want to create a new service version in the repository and associate the WCF service WSDL to that version. Associating the service means that you want to use a version already created in SO-Aware with the only purpose of managing and centralizing the service configuration in SO-Aware. The option for exporting a service will popup a dialog like the one bellow in which you can enter some basic information about the service version you want to create and the repository location. The option for associating a service will popup a dialog in which you can pick any existing service version repository and the application configuration file that you want to keep in sync for the service configuration. Two options are available for configuring a service, WCF Configuration or SO-Aware. The WCF Configuration option just tells the tool that the service will use the standard WCF configuration section “system.serviceModel” but that section must be updated and kept in sync with the configuration selected for the service in the repository. The SO-Aware configuration option will tell the tool that the service configuration will be resolved at runtime from the repository. For example, selecting SO-Aware will generate the following configuration in the selected application configuration file, <configuration> <configSections> <section name="serviceRepository" type="Tellago.ServiceModel.Governance.ServiceConfiguration.ServiceRepositoryConfigurationSection, Tellago.ServiceModel.Governance.ServiceConfiguration" /> </configSections> <serviceRepository url="http://localhost/soaware/servicerepository.svc"> <services> <service name="ref:HelloWorldService(1.0)@dev" type="SOAwareSampleService.HelloWorldService" /> </services> </serviceRepository> </configuration> As you can see the tool represents a great addition to the toolset that any developer can use to manage and centralize configuration for WCF services. In addition, it can be combined with other useful tools like WSCF.Blue (Web Service Contract First) for generating the service artifacts like schemas, service code or the service WSDL itself.

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• 3 Reasons You Need To Know Something About Every Technology

  - by Tim Murphy

  I make my living as a consultant and a general technologist.  I credit my success to the fact that I have never been afraid to pick up any product, language or platform needed to get the job done.  While Microsoft technologies I my mainstay, I have done work on mainframe and UNIX platforms and have worked with a wide variety of database engines.  Each one has it’s use and most times it is less expensive to find a way to communicate with an existing system than to replace it. So what are the main benefits of expending the effort to learn a new technology? New ways to solve problems Accelerate development Advise clients and get new business opportunities By new technology I mean ones that you haven’t had experience with before.  They don’t have to be the the one that just came out yesterday.  As they say, those who do not learn from history are bound to repeat it.  If you can learn something from an older technology it can be just as valuable as the shiny new one.  Either way, when you add another tool to your kit you get a new view on each problem you face.  This makes it easier to create a sound solution. The next thing you can learn from working with different products and techniques is how to more efficiently develop solve problems.  Many times if you are working with a new language you will find that there are specific design patterns that are used with it in normal use.  These can usually be applied with most languages.  You just needed to be exposed to them. The last point is about helping your clients and helping yourself.  If you can get in on technologies early you will have advantage over your competition in the market.  You will also be able to honestly advise you client on why they should or should not go with a new product.  Being able to compare products and their features is always an ability that stake holders appreciate. You don’t need to learn every detail of a product.  Learn enough to function and get an idea of how to use the technology.  Keep eating those technology Wheaties and you will be ready to go the distance in any project. del.icio.us Tags: Technology,technologists,technology generalist,Software Architecture

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• Certification Notes: 70-583 Designing and Developing Windows Azure Applications

  - by BuckWoody

  Last Updated: 02/01/2011 It’s time for another certification, and we’ve just release the 70-583 exam on Windows Azure. I’ve blogged my “study plans” here before on other certifications, so I thought I would do the same for this one. I’ll also need to take exam 70-513 and 70-516; but I’ll post my notes on those separately. None of these are “brain dumps” or any questions from the actual tests - just the books, links and notes I have from my studies. I’ll update these references as I’m studying, so bookmark this site and watch my Twitter and Facebook posts for when I’ll update them, or just subscribe to the RSS feed. A “Green” color on the check-block means I’ve done that part so far, red means I haven’t. First, I need to refresh my memory on some basic coding, so along with the Azure-specific information I’m reading the following general programming books: Introducing Microsoft .NET (Pro-Developer): link   Head First C#, 2E: A Learner's Guide to Real-World Programming with Visual C# and .NET: link Microsoft Visual C# 2008 Step by Step: link  c The first place to start is at the official site for the certification. link c On that page you’ll find several resources, and the first you should follow is the “Save to my learning” so you have a place to track everything. Then click the “Related Learning Plans” link and follow the videos and read the documentation in each of those bullets. There are six areas on the learning plan that you should focus on - make sure you open the learning plan to drill into the specifics. c Designing Data Storage Architecture (18%) Books I’m Reading: Links: My Notes: c Optimizing Data Access and Messaging (17%) Books I’m Reading: Links: My Notes: c Designing the Application Architecture (19%) Books I’m Reading: Applied Architecture Patterns on the Microsoft Platform: link Links: My Notes: c Preparing for Application and Service Deployment (15%) Books I’m Reading: Links: My Notes: c Investigating and Analyzing Applications (16%) Books I’m Reading: Links: My Notes: c Designing Integrated Solutions (15%) Books I’m Reading: Applied Architecture Patterns on the Microsoft Platform (2nd mention) Links: My Notes:

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• Creating a frozen bubble clone

  - by Vaughan Hilts

  This photo illustrates the environment: http://i.imgur.com/V4wbp.png I'll shoot the cannon, it'll bounce off the wall and it's SUPPOSED to stick to the bubble. It does at pretty much every other angle. The problem is always reproduced here, when hit off the wall into those bubbles. It also exists in other cases, but I'm not sure what triggers it. What actually happens: The ball will sometimes set to the wrong cell, and my "dropping" code will detect it as a loner and drop it off the stage. *There are many implementations of "Frozen Bubble" on the web, but I can't for the life of me find a good explanation as to how the algorithm for the "Bubble Sticking" works. * I see this: http://www.wikiflashed.com/wiki/BubbleBobble https://frozenbubblexna.svn.codeplex.com/svn/FrozenBubble/ But I can't figure out the algorithims... could anyone explain possibly the general idea behind getting the balls to stick? Code in question: //Counstruct our bounding rectangle for use var nX = currentBall.x + ballvX * gameTime; var nY = currentBall.y - ballvY * gameTime; var movingRect = new BoundingRectangle(nX, nY, 32, 32); var able = false; //Iterate over the cells and draw our bubbles for (var x = 0; x < 8; x++) { for (var y = 0; y < 12; y++) { //Get the bubble at this layout var bubble = bubbleLayout[x][y]; var rowHeight = 27; //If this slot isn't empty, draw if (bubble != null) { var bx = 0, by = 0; if (y % 2 == 0) { bx = x * 32 + 270; by = y * 32 + 45; } else { bx = x * 32 + 270 + 16; by = y * 32 + 45; } //Check var targetBox = new BoundingRectangle(bx, by, 32, 32); if (targetBox.intersects(movingRect)) { able = true; } } } } cellY = Math.round((currentBall.y - 45) / 32); if (cellY % 2 == 0) cellX = Math.round((currentBall.x - 270) / 32); else cellX = Math.round((currentBall.x - 270 - 16) / 32); Any ideas are very much welcome. Things I've tried: Flooring and Ceiling values Changing the wall bounce to a lower value Slowing down the ball None of these seem to affect it. Is there something in my math I'm not getting?

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• Revenue Recognition: Performance Obligation Pass a Hurdle

  - by Theresa Hickman

  I met up with Seamus Moran, our resident accounting expert, to get his thoughts about the latest happenings with IFRS. Last week, on March 13,  the comment period on the FASB and IASB exposure draft “Revenue From Contracts with Customers” closed.  FASB and IASB have just over 20 comment letters – a very small number.  The implication is that that the exposure draft does reflect general acceptance, and therefore will be published as both a US and Internationally Generally Accepted Accounting Standard. At a recent conference call, FASB and IASB expected to complete their report to both Boards on the comments by early summer, complete their deliberation of the comments by the fall and draft the final standard text by late this year. It is assumed the concept of Performance Obligations would become US GAAP and IFRS in place of the existing standards.  They confirmed that all existing US GAAP and IFRS guidelines would be withdrawn, and that they were in dialogue with the SEC on withdrawing the SEC guidelines on the revenue issue as well.The open question is when will Performance Obligations become effective?  The Boards have said that they would like this Revenue Recognition standard and the the Lease Accounting standard to be effective at the same time because what isn’t either insurance, interest, or a lease is a revenue arrangement.  However, ascertaining what is generally acceptable in respect of Leases is proving a little elusive, and the Boards have recently diverged a little on the P&L side of the accounting (although both are in agreement that there will be no off-balance sheet leases).  It is therefore likely that the Lease standard might be delayed. One wonders if the Boards will  define effectivity of the Revenue standard independently of the Lease standard or if they will stick with their resolve to make them co-effective.  The Boards have also said that neither standard will be effective before June 2015.Here is the gist of the new Revenue Recognition principle and the steps to apply it:Recognize revenue to depict the transfer of goods or services in an amount that reflects the consideration expected to be entitled in exchange for those goods and services.Steps to apply the core principles: Identify the contract with the customer Identify the separate performance obligations Determine the transaction price Allocate the the transaction price Recognize Revenue when a performance obligation is satisfied  

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• What is this algorithm for converting strings into numbers called?

  - by CodexArcanum

  I've been doing some work in Parsec recently, and for my toy language I wanted multi-based fractional numbers to be expressible. After digging around in Parsec's source a bit, I found their implementation of a floating-point number parser, and copied it to make the needed modifications. So I understand what this code does, and vaguely why (I haven't worked out the math fully yet, but I think I get the gist). But where did it come from? This seems like a pretty clever way to turn strings into floats and ints, is there a name for this algorithm? Or is it just something basic that's a hole in my knowledge? Did the folks behind Parsec devise it? Here's the code, first for integers: number' :: Integer -> Parser Integer number' base = do { digits <- many1 ( oneOf ( sigilRange base )) ; let n = foldl (\x d -> base * x + toInteger (convertDigit base d)) 0 digits ; seq n (return n) } So the basic idea here is that digits contains the string representing the whole number part, ie "192". The foldl converts each digit individually into a number, then adds that to the running total multiplied by the base, which means that by the end each digit has been multiplied by the correct factor (in aggregate) to position it. The fractional part is even more interesting: fraction' :: Integer -> Parser Double fraction' base = do { digits <- many1 ( oneOf ( sigilRange base )) ; let base' = fromIntegral base ; let f = foldr (\d x -> (x + fromIntegral (convertDigit base d))/base') 0.0 digits ; seq f (return f) Same general idea, but now a foldr and using repeated division. I don't quite understand why you add first and then divide for the fraction, but multiply first then add for the whole. I know it works, just haven't sorted out why. Anyway, I feel dumb not working it out myself, it's very simple and clever looking at it. Is there a name for this algorithm? Maybe the imperative version using a loop would be more familiar?

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• Why is multithreading often preferred for improving performance?

  - by user1849534

  I have a question, it's about why programmers seems to love concurrency and multi-threaded programs in general. I'm considering 2 main approaches here: an async approach basically based on signals, or just an async approach as called by many papers and languages like the new C# 5.0 for example, and a "companion thread" that manages the policy of your pipeline a concurrent approach or multi-threading approach I will just say that I'm thinking about the hardware here and the worst case scenario, and I have tested this 2 paradigms myself, the async paradigm is a winner at the point that I don't get why people 90% of the time talk about multi-threading when they want to speed up things or make a good use of their resources. I have tested multi-threaded programs and async program on an old machine with an Intel quad-core that doesn't offer a memory controller inside the CPU, the memory is managed entirely by the motherboard, well in this case performances are horrible with a multi-threaded application, even a relatively low number of threads like 3-4-5 can be a problem, the application is unresponsive and is just slow and unpleasant. A good async approach is, on the other hand, probably not faster but it's not worst either, my application just waits for the result and doesn't hangs, it's responsive and there is a much better scaling going on. I have also discovered that a context change in the threading world it's not that cheap in real world scenario, it's in fact quite expensive especially when you have more than 2 threads that need to cycle and swap among each other to be computed. On modern CPUs the situation it's not really that different, the memory controller it's integrated but my point is that an x86 CPUs is basically a serial machine and the memory controller works the same way as with the old machine with an external memory controller on the motherboard. The context switch is still a relevant cost in my application and the fact that the memory controller it's integrated or that the newer CPU have more than 2 core it's not bargain for me. For what i have experienced the concurrent approach is good in theory but not that good in practice, with the memory model imposed by the hardware, it's hard to make a good use of this paradigm, also it introduces a lot of issues ranging from the use of my data structures to the join of multiple threads. Also both paradigms do not offer any security abut when the task or the job will be done in a certain point in time, making them really similar from a functional point of view. According to the X86 memory model, why the majority of people suggest to use concurrency with C++ and not just an async approach ? Also why not considering the worst case scenario of a computer where the context switch is probably more expensive than the computation itself ?

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• Controlling soft errors and false alarms in SSIS

  - by Jim Giercyk

  If you are like me, you dread the 3AM wake-up call.  I would say that the majority of the pages I get are false alarms.  The alerts that require action often require me to open an SSIS package, see where the trouble is and try to identify the offending data.  That can be very time-consuming and can take quite a chunk out of my beauty sleep.  For those reasons, I have developed a simple error handling scenario for SSIS which allows me to rest a little easier.  Let me first say, this is a high level discussion; getting into the nuts and bolts of creating each shape is outside the scope of this document, but if you have an average understanding of SSIS, you should have no problem following along. In the Data Flow above you can see that there is a caution triangle.  For the purpose of this discussion I am creating a truncation error to demonstrate the process, so this is to be expected.  The first thing we need to do is to redirect the error output.  Double-clicking on the Query shape presents us with the properties window for the input.  Simply set the columns that you want to redirect to Redirect Row in the dropdown box and hit Apply. Without going into a dissertation on error handling, I will just note that you can decide which errors you want to redirect on Error and on Truncation.  Therefore, to override this process for a column or condition, simply do not redirect that column or condition. The next thing we want to do is to add some information about the error; specifically, the name of the package which encountered the error and which step in the package wrote the record to the error table.  REMEMBER: If you redirect the error output, your package will not fail, so you will not know where the error record was created without some additional information.    I added 3 columns to my error record; Severity, Package Name and Step Name.  Severity is just a free-form column that you can use to note whether an error is fatal, whether the package is part of a test job and should be ignored, etc.  Package Name and Step Name are system variables. In my package I have created a truncation situation, where the firstname column is 50 characters in the input, but only 4 characters in the output.  Some records will pass without truncation, others will be sent to the error output.  However, the package will not fail. We can see that of the 14 input rows, 8 were redirected to the error table. This information can be used by another step or another scheduled process or triggered to determine whether an error should be sent.  It can also be used as a historical record of the errors that are encountered over time.  There are other system variables that might make more sense in your infrastructure, so try different things.  Date and time seem like something you would want in your output for example.  In summary, we have redirected the error output from an input, added derived columns with information about the errors, and inserted the information and the offending data into an error table.  The error table information can be used by another step or process to determine, based on the error information, what level alert must be sent.  This will eliminate false alarms, and give you a head start when a genuine error occurs.

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• Mastering snow and Java development at jDays in Gothenburg

  - by JavaCecilia

  Last weekend, I took the train from Stockholm to Gothenburg to attend and present at the new Java developer conference jDays. It was professionally arranged in the Swedish exhibition hall close to the amusement park Liseberg and we got a great deal out of the top-level presenters and hallway discussions. Understanding and Improving Your Java Process Our main purpose was to spread information on JVM and our monitoring tools for Java processes, so I held a crash course in the most important terms and concepts if you want to affect the performance of your Java process. From the beginning - the JVM specification to interpretation of heap usage graphs. For correct analysis, you also need to understand something about process memory - you need space for the Java heap (-Xms for initial size and -Xmx for max heap size), but the process memory also contain the thread stacks (to a size of -Xss), JVM internal data structures used for keeping track of Java objects on the heap, method compilation/optimization, native libraries, etc. If you get long pause times, make sure to monitor your application, see the allocation rate and frequency of pause times.My colleague Klara Ward then held a presentation on the Java Mission Control product, the profiling and diagnostics tools suite for HotSpot, coming soon. The room was packed and very appreciated, Klara demonstrated four different scenarios, e.g. how to diagnose and fix latencies due to lock contention for logging.My German colleague, OpenJDK ambassador Dalibor Topic travelled to Sweden to do the second keynote on "Make the Future Java". He let us in on the coming features and roadmaps of Java, now delivering major versions on a two-year schedule (Java 7 2011, Java 8 2013, etc). Also letting us in on where to download early versions of 8, to report problems early on. Software Development in teams Being a scout leader, I'm drilled in different team building and workshop techniques, creating strong groups - of course, I had to attend Henrik Berglund's session on building successful teams. He spoke about the importance of clear goals, autonomy and agreed processes. Thomas Sundberg ended the conference by doing live remote pair programming with Alex in Rumania and a concrete tips for people wanting to try it out (for local collaboration, remember to wash and change clothes). Memory Master Keynote The conference keynote was delivered by the Swedish memory master Mattias Ribbing, showing off by remembering the order of a deck of cards he'd seen once. He made it interactive by forcing the audience to learn a memory mastering technique of remembering ten ordered things by heart, asking us to shout out the order backwards and we made it! I desperately need this - bought the book, will get back on the subject. Continuous Delivery The most impressive presenter was Axel Fontaine on Continuous Delivery. Very well prepared slides with key images of his message and moved about the stage like a rock star. The topic is of course highly interesting, how to create an infrastructure enabling immediate feedback to developers and ability to release your product several times per day. Tomek Kaczanowski delivered a funny and useful presentation on good and bad tests, providing comic relief with poorly written tests and the useful rules of thumb how to rewrite them. To conclude, we had a great time and hope to see you at jDays next year :)

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• An invitation to join a JDeveloper and ADF productivity clinic (and more!) at KScope

  - by Chris Muir

  Would you like a chance to influence Oracle's decisions on tool usability and productivity? If you're attending ODTUG's Kaleidoscope conference this year in San Antonio, Oracle would like to invite you to participate in our Usability Activity Research and separately our JDeveloper and ADF Productivity Clinics with our experienced user experience teams.  The teams are keen to hear what you have to say about your experiences with our tools in general and specifically JDeveloper and ADF.  The details of each event are described below. Invitation to Usability Activity - Sunday June 24th to Wednesday June 27th Oracle is constantly working on new tools and new features for developers, and invites YOU to become a key part of the process!  As a special addition to Kscope 12, Oracle will be conducting onsite usability research in the Alyssum room, from Sunday June 24 to Wednesday June 27. Usability activities are scheduled ahead of time for participants' convenience.  If you would like to take part, please fill out this form to let us know of the session(s) that you would like to attend and your development experience. You will be emailed with your scheduled session before the start of the conference. JDeveloper and ADF Productivity Clinic - Thursday June 28th Are you concerned that Java, Oracle ADF or JDeveloper is difficult? Is JDeveloper making you jump through hoops?  Do you hate a particular dialog or feature of JDeveloper? Well, come and get things off your chest! Oracle is hosting a product management and user experience clinic where we want to hear about your issues and concerns. What's difficult to use?  What doesn't work the way you want, and how would you want it to work?  What isn't behaving like your current favorite tool?  If we can't help on you the spot, we'll take your feedback and use it to improve the product experience.  A great opportunity to get answers, or get improvements. Drop by the Alyssum room, anytime from 8:30 to 10:30 on Thursday, June 28. We look forward to seeing you at KScope soon! 

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• Halloween: Season for Java Embedded Internet of Spooky Things (IoST) (Part 4)

  - by hinkmond

  And now here's the Java code that you'll need to read your ghost sensor on your Raspberry Pi The general idea is that you are using Java code to access the GPIO pin on your Raspberry Pi where the ghost sensor (JFET trasistor) detects minute changes in the electromagnetic field near the Raspberry Pi and will change the GPIO pin to high (+3 volts) when something is detected, otherwise there is no value (ground). Here's that Java code: try { /*** Init GPIO port(s) for input ***/ // Open file handles to GPIO port unexport and export controls FileWriter unexportFile = new FileWriter("/sys/class/gpio/unexport"); FileWriter exportFile = new FileWriter("/sys/class/gpio/export"); for (String gpioChannel : GpioChannels) { System.out.println(gpioChannel); // Reset the port File exportFileCheck = new File("/sys/class/gpio/gpio"+gpioChannel); if (exportFileCheck.exists()) { unexportFile.write(gpioChannel); unexportFile.flush(); } // Set the port for use exportFile.write(gpioChannel); exportFile.flush(); // Open file handle to input/output direction control of port FileWriter directionFile = new FileWriter("/sys/class/gpio/gpio" + gpioChannel + "/direction"); // Set port for input directionFile.write(GPIO_IN); } /*** Read data from each GPIO port ***/ RandomAccessFile[] raf = new RandomAccessFile[GpioChannels.length]; int sleepPeriod = 10; final int MAXBUF = 256; byte[] inBytes = new byte[MAXBUF]; String inLine; int zeroCounter = 0; // Get current timestamp with Calendar() Calendar cal; DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss.SSS"); String dateStr; // Open RandomAccessFile handle to each GPIO port for (int channum=0; channum And, then we just load up our Java SE Embedded app, place each Raspberry Pi with a ghost sensor attached in strategic locations around our Santa Clara office (which apparently is very haunted by ghosts from the Agnews Insane Asylum 1906 earthquake), and watch our analytics for any ghosts. Easy peazy. See the previous posts for the full series on the steps to this cool demo: Halloween: Season for Java Embedded Internet of Spooky Things (IoST) (Part 1) Halloween: Season for Java Embedded Internet of Spooky Things (IoST) (Part 2) Halloween: Season for Java Embedded Internet of Spooky Things (IoST) (Part 3) Halloween: Season for Java Embedded Internet of Spooky Things (IoST) (Part 4) Hinkmond

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• When row estimation goes wrong

  - by Dave Ballantyne

  Whilst working at a client site, I hit upon one of those issues that you are not sure if that this is something entirely new or a bug or a gap in your knowledge. The client had a large query that needed optimizing.  The query itself looked pretty good, no udfs, UNION ALL were used rather than UNION, most of the predicates were sargable other than one or two minor ones.  There were a few extra joins that could be eradicated and having fixed up the query I then started to dive into the plan. I could see all manor of spills in the hash joins and the sort operations,  these are caused when SQL Server has not reserved enough memory and has to write to tempdb.  A VERY expensive operation that is generally avoidable.  These, however, are a symptom of a bad row estimation somewhere else, and when that bad estimation is combined with other estimation errors, chaos can ensue. Working my way back down the plan, I found the cause, and the more I thought about it the more i came convinced that the optimizer could be making a much more intelligent choice. First step is to reproduce and I was able to simplify the query down a single join between two tables, Product and ProductStatus,  from a business point of view, quite fundamental, find the status of particular products to show if ‘active’ ,’inactive’ or whatever. The query itself couldn’t be any simpler The estimated plan looked like this: Ignore the “!” warning which is a missing index, but notice that Products has 27,984 rows and the join outputs 14,000. The actual plan shows how bad that estimation of 14,000 is : So every row in Products has a corresponding row in ProductStatus.  This is unsurprising, in fact it is guaranteed,  there is a trusted FK relationship between the two columns.  There is no way that the actual output of the join can be different from the input. The optimizer is already partly aware of the foreign key meta data, and that can be seen in the simplifiction stage. If we drop the Description column from the query: the join to ProductStatus is optimized out. It serves no purpose to the query, there is no data required from the table and the optimizer knows that the FK will guarantee that a matching row will exist so it has been removed. Surely the same should be applied to the row estimations in the initial example, right ?  If you think so, please upvote this connect item. So what are our options in fixing this error ? Simply changing the join to a left join will cause the optimizer to think that we could allow the rows not to exist. or a subselect would also work However, this is a client site, Im not able to change each and every query where this join takes place but there is a more global switch that will fix this error,  TraceFlag 2301. This is described as, perhaps loosely, “Enable advanced decision support optimizations”. We can test this on the original query in isolation by using the “QueryTraceOn” option and lo and behold our estimated plan now has the ‘correct’ estimation. Many thanks goes to Paul White (b|t) for his help and keeping me sane through this

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• SharePoint Thoughts

  - by Tim Murphy

  I was listening to .NET Rocks episode #713 and it got me thinking about a number of SharePoint related topics. I have been working with SharePoint since the 2001 product came out and have watched it evolve over the years.  Today SharePoint is one of the most powerful and flexible products in the market.  Of course that doesn’t mean there isn’t room for improvement (a lot of improvement in fact) and with much power comes much responsibility. My main gripe these days is that you have to develop on a server instance.  This adds a real barrier to entry for developers.  You either have to run VMWare or Hyper-V on your developer machine or actually develop on your dev server for most tasks.  Yes, there is a way to setup a Windows 7 machine with the SharePoint components but it is very hackish. Beyond that the tools in VS2010 are a great leap forward from past generations.  Not requiring a separate package creation tool is not the least of the improvements.  Better workflow and web part development have also eased the burden of many developers. The other thing the show brought up in my thoughts was more around usage.  Users want to be able to self server everything without regard to what affect that has on leveraging their data from a corporate perspective.  My coworkers who work on Lotus Notes ask why the user can’t just do what ever they want? Part of the reason is that those features have not been built, but the other part is that giving them those features is often like giving an infant a loaded hand gun.  You can do it but it doesn’t make it the smart thing to do. As with any tool that is going to be used in the enterprise it should be subject to governance.  If controls are not in place as they said in the episode of DNR the document libraries and I believe SharePoint in general starts to look as disarrayed and unusable as a shared drive.  Consider these factors before giving into every whim of the users.  You should be able to explain to them the tradeoffs of giving them full control versus being able to leverage the information they collect to the benefit of the organization. These are just a couple of the thoughts that were triggered by the show.  I’m sure there are more discussions that can be had.  Feel free to leave your comments about the pros and cons of SharePoint. del.icio.us Tags: .NET Rocks,SharePoint,software development

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• SharePoint For Newbie Developers: Code Scope

  - by Mark Rackley

  So, I continue to try to come up with diagrams and information to help new SharePoint developers wrap their heads around this SharePoint beast, especially when those newer to development are on my team. To that end, I drew up the below diagram to help some of our junior devs understand where/when code is being executed in SharePoint at a high level. Note that I say “High Level”… This is a simplistic diagram that can get a LOT more complicated if you want to dive in deeper.  For the purposes of my lesson it served its purpose well. So, please no comments from you peanut gallery about information 3 levels down that’s missing unless it adds to the discussion.  Thanks So, the diagram below details where code is executed on a page load and gives the basic flow of the page load. There are actually many more steps, but again, we are staying high level here. I just know someone is still going to say something like “Well.. actually… the dlls are getting executed when…”  Anyway, here’s the diagram with some information I like to point out: Code Scope / Where it is executed So, looking at the diagram we see that dlls and XSL are executed on the server and that JavaScript/jQuery are executed on the client. This is the main thing I like to point out for the following reasons: XSL (for the most part) is faster than JavaScript I actually get this question a lot. Since XSL is executed on the server less data is getting passed over the wire and a beefier machine (hopefully) is doing the processing. The outcome of course is better performance. When You are using jQuery and making Web Service calls you are building XML strings and sending them to the server, then ALL the results come back and the client machine has to parse through the XML and use what it needs and ignore the rest (and there is a lot of garbage that comes back from SharePoint Web Service calls). XSL and JavaScript cannot work together in the same scope Let me clarify. JavaScript can send data back to SharePoint in postbacks that XSL can then use. XSL can output JavaScript and initiate JavaScript variables.  However, XSL cannot call a JavaScript method to get a value and JavaScript cannot directly interact with XSL and call its templates. They are executed in there scope only. No crossing of boundaries here. So, what does this all mean? Well, nothing too deep. This is just some basic fundamental information that all SharePoint devs need to understand. It will help you determine what is the best solution for your specific development situation and it will help the new guys understand why they get an error when trying to call a JavaScript Function from within XSL.  Let me know if you think quick little blogs like this are helpful or just add to the noise. I could probably put together several more that are similar.  As always, thanks for stopping by, hope you learned something new.

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• Real-Time Multi-User Gaming Platform

  - by Victor Engel

  I asked this question at Stack Overflow but was told it's more appropriate here, so I'm posting it again here. I'm considering developing a real-time multi-user game, and I want to gather some information about possibilities before I do some real development. I've thought about how best to ask the question, and for simplicity, the best way that occurred to me was to make an analogy to the field (or playground) game darebase. In the field game of darebase, there are two or more bases. To start, there is one team on each base. The game is a fancy game of tag. When two people meet out in the field, the person who left his base most recently timewise captures the other person. They then return to that person's base. Play continues until everyone is part of the same team. So, analogizing this to an online computer game, let's suppose there are an indefinite number of bases. When a person starts up the game, he has a team that is located at, for example, his current GPS coordinates. It could be a virtual world, but for sake of argument, let's suppose the virtual world corresponds to the player's actual GPS coordinates. The game software then consults the database to see where the closest other base is that is online, and the two teams play their game of virtual tag. Note that the user of the other base could have a different base than the one run by the current user as the closest base to him, in which case, he would be in two simultaneous battles, one with each base. When they go offline, the state of their players is saved on a server somewhere. Game logic calls for the players to have some automaton-logic of some sort, so they can fend for themselves in a limited way using basic rules, until their user goes online again. The user doesn't control the players' movements directly, but issues general directives that influence the players' movement logic. I think this analogy is good enough to frame my question. What sort of platforms are available to develop this sort of game? I've been looking at smartfoxserver, but I'm not convinced yet that it is the best option or even that it will work at all. One possibility, of course, would be to roll out my own web server, but I'd rather not do that if there is an existing service out there already that I could tap into. I will be developing for iOS devices at first. So any suggestions would be greatly appreciated. I think I need to establish the architecture first before proceeding with this project. Note that darbase is not the game I intend to implement, but, upon reflection, that might not be a bad idea either.

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• 5 ways to stop code thrashing&hellip;

  - by MarkPearl

  A few days ago I was programming on a personal project and hit a roadblock. I was applying the MVVM pattern and for some reason my view model was not updating the view when the state changed??? I had applied this pattern many times before and had never had this problem. It just didn’t make sense. So what did I do… I did what anyone would have done in my situation and looked to pass the blame to someone or something else. I tried to blame one of the inherited base classes, but it looked fine, then to Visual Studio, but it seemed to be fine and eventually to any random segment of code I came across. My elementary problem had now mushroomed into one that had lost any logical basis and I was in thrashing mode! So what to do when you begin to thrash? 1) Do a general code cleanup – Now there is a difference between cleaning code and changing code . When you thrash you change code and you want to avoid this. What you really want to do is things like rename variables to have better meaning and go over your comments. 2) Do a proof of concept – if cleaning code doesn’t help. The  you want to isolate the problem and identify the key concepts. When you isolate code you ideally want it to be in a totally separate project with as little complexity as possible. Make the building blocks and try and replicate the functionality that you are getting in your current application. 3) Phone a friend – I have found speaking to someone else about the problem generally helps me solve any thrashing issues I am having. Usually they don’t even have to say anything to solve the problem, just you talking them through the problem helps you get clarity of mind. 4) Let the dust settle – Sometimes time is the best solution. I have had a few problems that no matter who I discussed them with and no matter how much code cleaning I had done I just couldn’t seem to fix it. My brain just seemed to be going in circles. A good nights rest has always helped and often just the break away from the problem has helped me find a solution. 5) Stack overflow it – So similar to phone a friend. I am really surprised to see what a melting pot stack overflow has been and what a help it has been in solving technology specific problems. Just be considerate to those using the site and explain clearly exactly what problem you are having and the technologies you are using or else you will probably not get any useful help…

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• How granular should a command be in a CQ[R]S model?

  - by Aaronaught

  I'm considering a project to migrate part of our WCF-based SOA over to a service bus model (probably nServiceBus) and using some basic pub-sub to achieve Command-Query Separation. I'm not new to SOA, or even to service bus models, but I confess that until recently my concept of "separation" was limited to run-of-the-mill database mirroring and replication. Still, I'm attracted to the idea because it seems to provide all the benefits of an eventually-consistent system while sidestepping many of the obvious drawbacks (most notably the lack of proper transactional support). I've read a lot on the subject from Udi Dahan who is basically the guru on ESB architectures (at least in the Microsoft world), but one thing he says really puzzles me: As we get larger entities with more fields on them, we also get more actors working with those same entities, and the higher the likelihood that something will touch some attribute of them at any given time, increasing the number of concurrency conflicts. [...] A core element of CQRS is rethinking the design of the user interface to enable us to capture our users’ intent such that making a customer preferred is a different unit of work for the user than indicating that the customer has moved or that they’ve gotten married. Using an Excel-like UI for data changes doesn’t capture intent, as we saw above. -- Udi Dahan, Clarified CQRS From the perspective described in the quotation, it's hard to argue with that logic. But it seems to go against the grain with respect to SOAs. An SOA (and really services in general) are supposed to deal with coarse-grained messages so as to minimize network chatter - among many other benefits. I realize that network chatter is less of an issue when you've got highly-distributed systems with good message queuing and none of the baggage of RPC, but it doesn't seem wise to dismiss the issue entirely. Udi almost seems to be saying that every attribute change (i.e. field update) ought to be its own command, which is hard to imagine in the context of one user potentially updating hundreds or thousands of combined entities and attributes as it often is with a traditional web service. One batch update in SQL Server may take a fraction of a second given a good highly-parameterized query, table-valued parameter or bulk insert to a staging table; processing all of these updates one at a time is slow, slow, slow, and OLTP database hardware is the most expensive of all to scale up/out. Is there some way to reconcile these competing concerns? Am I thinking about it the wrong way? Does this problem have a well-known solution in the CQS/ESB world? If not, then how does one decide what the "right level" of granularity in a Command should be? Is there some "standard" one can use as a starting point - sort of like 3NF in databases - and only deviate when careful profiling suggests a potentially significant performance benefit? Or is this possibly one of those things that, despite several strong opinions being expressed by various experts, is really just a matter of opinion?

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• How employable am I as a programmer?

  - by dsimcha

  I'm currently a Ph.D. student in Biomedical Engineering with a concentration in computational biology and am starting to think about what I want to do after graduate school. I feel like I've accumulated a lot of programming skills while in grad school, but taken a very non-traditional path to learning all this stuff. I'm wondering whether I would have an easy time getting hired as a programmer and could fall back on that if I can't find a good job directly in my field, and if so whether I would qualify for a more prestigious position than "code monkey". Things I Have Going For Me Approximately 4 years of experience programming as part of my research. I believe I have a solid enough grasp of the fundamentals that I could pick up new languages and technologies pretty fast, and could demonstrate this in an interview. Good math and statistics skills. An extensive portfolio of open source work (and the knowledge that working on these projects implies): I wrote a statistics library in D, mostly from scratch. I wrote a parallelism library (parallel map, reduce, foreach, task parallelism, pipelining, etc.) that is currently in review for adoption by the D standard library. I wrote a 2D plotting library for D against the GTK Cairo backend. I currently use it for most of the figures I make for my research. I've contributed several major performance optimizations to the D garbage collector. (Most of these were low-hanging fruit, but it still shows my knowledge of low-level issues like memory management, pointers and bit twiddling.) I've contributed lots of miscellaneous bug fixes to the D standard library and could show the change logs to prove it. (This demonstrates my ability read other people's code.) Things I Have Going Against Me Most of my programming experience is in D and Python. I have very little to virtually no experience in the more established, "enterprise-y" languages like Java, C# and C++, though I have learned a decent amount about these languages from small, one-off projects and discussions about language design in the D community. In general I have absolutely no knowledge of "enterprise-y" technlogies. I've never used a framework before, possibly because most reusable code for scientific work and for D tends to call itself a "library" instead. I have virtually no formal computer science/software engineering training. Almost all of my knowledge comes from talking to programming geek friends, reading blogs, forums, StackOverflow, etc. I have zero professional experience with the official title of "developer", "software engineer", or something similar.

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• Portland Silverlight User Group: WP7 &amp; XNA &ndash; I survived.

  - by George Clingerman

  Last night I gave a talk to the Portland Silverlight User Group. http://www.portlandsilverlight.net/Meetings/Details/15 And I survived (which you should have probably already figured out since you’re reading this post AND that’s what I titled it…) Really though it was a fantastic time and I had a lot of fun! I was a little nervous getting ready for it, but I’m always a little nervous getting ready for things. I had the game all written,  I knew the general flow for what the talk was going to be. I read over Scott Hanselman’s 11 Top Tips for a Successful Technical presentation (which has become something I do EVERY time I’m preparing for a talk). I gave myself a brief list of points I wanted to make sure I covered or worked into the talk. But then I was ready and I waited. I hate the waiting. It makes me nervous. Once I was up in front of the room though with my laptop open and some XNA code in front of me, my nerves go away. Then I’m ready. I know XNA, I love talking about XNA and I love sharing what I know and hearing questions that make me think. And hopefully that came through while I was talking. I had a freaking blast. The swag went quickly (and I was even able to hand out some XNA 2.0 books that have been around forever!) and the pizza was been gobbled down. I started the talk at about 6:10 and managed to cover a very brief intro to programming against the game loop (it’s a different concept and one that seems to trip a lot of people up getting started with game development) and then rolled into making a basic 2D game for Windows Phone 7 using XNA. And I finished the whole thing before 8:30. Wahoo! I’m planning on posting the source code and assets on my site so those should be coming soon. And to make things even better, they recorded the whole thing on video so everyone will get to see me pretend I can speak! Just wait till you hear the new song I wrote for this talk…

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• Focusing on Mobile @ Oracle OpenWorld

  - by Carlos Chang

  Plenty of exciting trends in the industry today: Cloud, Big Data, Mobile, etc. The first two are amazing of course, but for me, it's mobile, mobile and... MOBILE.   Why? Think back to the mozilla browser (Marc Andreessen's mozilla, not today's mozilla.org), Netscape and the nascent beginnings of the World Wide Web. Amazing times. Companies were just starting to set up their home pages, basic HTML, hyperlinks, images, ooooh, aaaah.  Yahoo! was *the* search engine back then. :-\   Anywhoo, I would pose that mobile today, we are in a similar junction. Sure, there's millions of apps on Apple's App Store and Google Play, but within the enterprise, it's just getting started. I'm talking about going beyond the simple, tactical apps such as calendaring, contacts or directory service lookup. And while mobile first a common mantra, I'm referring to mobile plus which includes and looks upon the whole enterprise holistically and adds new parameters, such as your GPS location, perhaps even your vital signs. (Apple's health kit?)  Everything is going mobile. Everything connected. But with the enterprise - scalability, security, integration, app management, user management, etc. Amazing times ahead. Ok, got that off my mind. Oracle OpenWorld 2014 - Going Mobile!  If you're coming to the big dance, I've highlighted some key mobile sessions below. And if you see me around, and there's a bar within reach, high five me for a beer. I mean, if you read this far, and didn't already jump to the list below, I think you deserve one.   Cheers!  Monday, 9/29/14 at 10:15 AM - General Session: Time for You to Rethink Mobile? Oracle Mobile Strategy and Roadmap Tuesday, 9/30/14 @ 12:00 PM; MW3020 - Develop and Deploy Mobile Applications with Oracle’s Mobile Wednesday, 10/1/2014 @10:15 AM; MW 3022 Introduction to Oracle Mobile Application Framework Wednesday, 10/1/2014 @11:30 AM Accelerate Enterprise Mobility with Oracle Mobile Cloud Service Click here to view the complete Focus on Mobile sessions at this years Oracle OpenWorld 2014, and don't forget to follow @OracleMobile on Twitter. 

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• Accessing SQL Server data from iOS apps

  - by RobertChipperfield

  Almost all mobile apps need access to external data to be valuable. With a huge amount of existing business data residing in Microsoft SQL Server databases, and an ever-increasing drive to make more and more available to mobile users, how do you marry the rather separate worlds of Microsoft's SQL Server and Apple's iOS devices? The classic answer: write a web service layer Look at any of the questions on this topic asked in Internet discussion forums, and you'll inevitably see the answer, "just write a web service and use that!". But what does this process gain? For a well-designed database with a solid security model, and business logic in the database, writing a custom web service on top of this just to access some of the data from a different platform seems inefficient and unnecessary. Desktop applications interact with the SQL Server directly - why should mobile apps be any different? The better answer: the iSql SDK Working along the lines of "if you do something more than once, make it shared," we set about coming up with a better solution for the general case. And so the iSql SDK was born: sitting between SQL Server and your iOS apps, it provides the simple API you're used to if you've been developing desktop apps using the Microsoft SQL Native Client. It turns out a web service remained a sensible idea: HTTP is much more suited to the Big Bad Internet than SQL Server's native TDS protocol, removing the need for complex configuration, firewall configuration, and the like. However, rather than writing a web service for every app that needs data access, we made the web service generic, serving only as a proxy between the SQL Server and a client library integrated into the iPhone or iPad app. This client library handles all the network communication, and provides a clean API. OSQL in 25 lines of code As an example of how to use the API, I put together a very simple app that allowed the user to enter one or more SQL statements, and displayed the results in a rather primitively formatted text field. The total amount of Objective-C code responsible for doing the work? About 25 lines. You can see this in action in the demo video. Beta out now - your chance to give us your suggestions! We've released the iSql SDK as a beta on the MobileFoo website: you're welcome to download a copy, have a play in your own apps, and let us know what we've missed using the Feedback button on the site. Software development should be fun and rewarding: no-one wants to spend their time writing boiler-plate code over and over again, so stop writing the same web service code, and start doing exciting things in the new world of mobile data!

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• Microsoft and Application Architectures

  Microsoft has dealt with several kinds of application architectures to include but not limited to desktop applications, web applications, operating systems, relational database systems, windows services, and web services. Because of the size and market share of Microsoft, virtually every modern language works with or around a Microsoft product. Some of the languages include: Visual Basic, VB.Net, C#, C++, C, ASP.net, ASP, HTML, CSS, JavaScript, Java and XML. From my experience, Microsoft strives to maintain an n-tier application standard where an application is comprised of multiple layers that perform specific functions, for example: presentation layer, business layer, data access layer are three general layers that just about every formally structured application contains. The presentation layer contains anything to do with displaying information to the screen and how it appears on the screen. The business layer is the middle man between the presentation layer and data access layer and transforms data from the data access layer in to useable information to be stored later or sent to an output device through the presentation layer. The data access layer does as its name implies, it allows the business layer to access data from a data source like MS SQL Server, XML, or another data source. One of my favorite technologies that Microsoft has come out with recently is the .Net Framework. This framework allows developers to code an application in multiple languages and compiles them in to one intermediate language called the Common Language Runtime (CLR). This allows VB and C# developers to work seamlessly together as if they were working in the same project. The only real disadvantage to using the .Net Framework is that it only natively runs on Microsoft operating systems. However, Microsoft does control a majority of the operating systems currently installed on modern computers and servers, especially with personal home computers. Given that the Microsoft .Net Framework is so flexible it is an ideal for business to develop applications around it as long as they wanted to commit to using Microsoft technologies and operating systems in the future. I have been a professional developer for about 9+ years now and have seen the .net framework work flawlessly in just about every instance I have used it. In addition, I have used it to develop web applications, mobile phone applications, desktop applications, web service applications, and windows service applications to name a few.

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• Investigating Strategies For Functional Decomposition

  - by Liam McLennan

  Introducing Functional Decomposition Before I begin I must apologise. I think I am using the term ‘functional decomposition’ loosely, and probably incorrectly. For the purpose of this article I use functional decomposition to mean the recursive splitting of a large problem into increasingly smaller ones, so that the one large problem may be solved by solving a set of smaller problems. The justification for functional decomposition is that the decomposed problem is more easily solved. As software developers we recognise that the smaller pieces are more easily tested, since they do less and are more cohesive. Functional decomposition is important to all scientific pursuits. Once we understand natural selection we can start to look for humanities ancestral species, once we understand the big bang we can trace our expanding universe back to its origin. Isaac Newton acknowledged the compositional nature of his scientific achievements: If I have seen further than others, it is by standing upon the shoulders of giants   The Two Strategies For Functional Decomposition of Computer Programs Private Methods When I was working on my undergraduate degree I was taught to functionally decompose problems by using private methods. Consider the problem of painting a house. The obvious solution is to solve the problem as a single unit: public void PaintAHouse() { // all the things required to paint a house ... } We decompose the problem by breaking it into parts: public void PaintAHouse() { PaintUndercoat(); PaintTopcoat(); } private void PaintUndercoat() { // everything required to paint the undercoat } private void PaintTopcoat() { // everything required to paint the topcoat } The problem can be recursively decomposed until a sufficiently granular level of detail is reached: public void PaintAHouse() { PaintUndercoat(); PaintTopcoat(); } private void PaintUndercoat() { prepareSurface(); fetchUndercoat(); paintUndercoat(); } private void PaintTopcoat() { fetchPaint(); paintTopcoat(); } According to Wikipedia, at least one computer programmer has referred to this process as “the art of subroutining”. The practical issues that I have encountered when using private methods for decomposition are: To preserve the top level API all of the steps must be private. This means that they can’t easily be tested. The private methods often have little cohesion except that they form part of the same solution. Decomposing to Classes The alternative is to decompose large problems into multiple classes, effectively using a class instead of each private method. The API delegates to related classes, so the API is not polluted by the sub-steps of the problem, and the steps can be easily tested because they are each in their own highly cohesive class. Additionally, I think that this technique facilitates better adherence to the Single Responsibility Principle, since each class can be decomposed until it has precisely one responsibility. Revisiting my previous example using class composition: public class HousePainter { private undercoatPainter = new UndercoatPainter(); private topcoatPainter = new TopcoatPainter(); public void PaintAHouse() { undercoatPainter.Paint(); topcoatPainter.Paint(); } } Summary When decomposing a problem there is more than one way to represent the sub-problems. Using private methods keeps the logic in one place and prevents a proliferation of classes (thereby following the four rules of simple design) but the class decomposition is more easily testable and more compatible with the Single Responsibility Principle.

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• Partner BI Applications 4-Day Hands-on Training Workshop

  - by Mike.Hallett(at)Oracle-BI&EPM

  Normal 0 false false false EN-GB X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;} 12th - 15th February 2012, Oracle Reading (UK) - REGISTER NOW This training will provide attendees with an in-depth working understanding of the architecture, the technical and the functional content of the Oracle Business Intelligence Applications, whilst also providing an understanding of their installation, configuration and extension. The course will cover the following topics: Overview of Oracle Business Intelligence Applications Oracle BI Applications Fundamentals and Features Configuring BI Applications for Oracle E-Business Suite Understanding BI Applications Architecture Fundamentals of BI Applications Security Prerequisites - This training is only for OPN member Partners. Good understanding of basic data warehousing concepts Hands on experience in Oracle Business Intelligence Enterprise Edition Hands on experience in Informatica Good understanding of any of the following Oracle EBS modules: General Ledger, Accounts Receivables, Accounts Payables Some understanding of  Oracle BI Applications is required (See Sales & Technical Tutorials for OBI, BI-Apps and Hyperion EPM)  Please note that attendees are required to bring a laptop. Laptop 4GB RAM-Recognized by Windows 64 bits 80GB free space in Hard drive or External Device CPU Core 2 Duo or Higher Operating System Requirements Windows 7, Windows XP, Windows 2003 NOT ALLOWED with Windows Vista An Administrator User

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• Best way to implement a simple bullet trajectory

  - by AirieFenix

  I searched and searched and although it's a fair simple question, I don't find the proper answer but general ideas (which I already have). I have a top-down game and I want to implement a gun which shoots bullets that follow a simple path (no physics nor change of trajectory, just go from A to B thing). a: vector of the position of the gun/player. b: vector of the mouse position (cross-hair). w: the vector of the bullet's trajectory. So, w=b-a. And the position of the bullet = [x=x0+speed*time*normalized w.x , y=y0+speed*time * normalized w.y]. I have the constructor: public Shot(int shipX, int shipY, int mouseX, int mouseY) { //I get mouse with Gdx.input.getX()/getY() ... this.shotTime = TimeUtils.millis(); this.posX = shipX; this.posY = shipY; //I used aVector = aVector.nor() here before but for some reason didn't work float tmp = (float) (Math.pow(mouseX-shipX, 2) + Math.pow(mouseY-shipY, 2)); tmp = (float) Math.sqrt(Math.abs(tmp)); this.vecX = (mouseX-shipX)/tmp; this.vecY = (mouseY-shipY)/tmp; } And here I update the position and draw the shot: public void drawShot(SpriteBatch batch) { this.lifeTime = TimeUtils.millis() - this.shotTime; //position = positionBefore + v*t this.posX = this.posX + this.vecX*this.lifeTime*speed*Gdx.graphics.getDeltaTime(); this.posY = this.posY + this.vecY*this.lifeTime*speed*Gdx.graphics.getDeltaTime(); ... } Now, the behavior of the bullet seems very awkward, not going exactly where my mouse is (it's like the mouse is 30px off) and with a random speed. I know I probably need to open the old algebra book from college but I'd like somebody says if I'm in the right direction (or points me to it); if it's a calculation problem, a code problem or both. Also, is it possible that Gdx.input.getX() gives me non-precise position? Because when I draw the cross-hair it also draws off the cursor position. Sorry for the long post and sorry if it's a very basic question. Thanks!

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