Search Results

Search found 1364 results on 55 pages for 'jump'.

Page 42/55 | < Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >

• IIS not starting: The process cannot access the file because it is being used by another process

  - by Rick Strahl

  Ok, apparently a few people knew about this issue, but it is new to me and has caused me nearly an hour to track down today. What happened is that I’ve been working all day doing some final pre-deployment testing of several tools on my local dev machine. In the process I’ve been starting and stopping several IIS 7 Web sites. At some point I was done and just wanted to start my Default Web Site again and found this  little gem of an error message popping up: The process cannot access the file because it is being used by another process. (Exception from HRESULT: 0x80070020) A lot of headless running around ensued after this, trying to figure out why IIS wouldn’t start. Oddly some sites started right up, others didn’t. I killed INetInfo, all worker processes, tried IISReset a million times and even rebooted – all to no avail. What gives? Skype, you evil Bastard! As it turns out the culprit is – drum roll please - Skype!  What, you may ask, does Skype have to do with IIS and Web Requests? It looks like recent versions of Skype have an option to run over Port 80 and 443 to allow running over corporate firewalls. Which is actually a nice feature that lets Skype work just about anywhere. What’s not so cool is that IIS fails to start up when another application is already using the same port that a Web site is mapped to. In the case of my dev site that’d be port 80 and Skype was hogging it. To fix this issue you can stop Skype from using port 80 and 443 which quickly fixes the problem. Or stop Skype. Duh! To permanently fix the problem in Skype find the option on the Options | Connection tab and uncheck the Use port 80/443 option: Oddly I haven’t run into this problem even though my setup hasn’t changed in quite some time. It appears that it’s bad startup timing that causes this problem to occur. Whatever the circumstance was, Skype somehow ended up starting before IIS.  If Skype is started after IIS has started it will automatically opt for other ports and not use port 80 and so there’s no problem. It’s easy to demonstrate this behavior if you’re looking for it: Stop IIS Stop Skype Start Skype and make a test call Start IIS And voila your error is ready for you! This really shouldn’t be a problem except that it would be really nice if IIS could give a more helpful error message when it can fire up a site because a port is blocked. “The process cannot access a file” is really not a very helpful error message in this scenario… I/O port / file ah what the heck it’s all the same to Windows. Right! I’ve run into this situation quite a bit with other, albeit more obvious applications like running Apache on the local machine for testing and then trying to run an IIS application. Same situation,  although it’s been a while – pre IIS 7 and I think previous versions of IIS actually gave more useful error messages for port blockages and that would be helpful. On the way to figuring this out I ran into some pretty humorous forum posts though with people ragging on why the hell you would be running IIS. Or Skype. The misinformed paranoia police out in full force so to say :-). It’ll be nice to start running IIS Express once Visual Studio 2010 SP1 gets released. Anyway, no surprise that Skype didn’t jump out at me as the culprit right away and I was left fumbling for a while until the Internet came to the rescue. I’m not the first to have found this for sure – I posted a message on Twitter and dozens of people replied they’d run into this before as well. Seems worth mentioning again though – since I’m sure to forget that this happened in a year from now when I hit that same error. Maybe I’ll even find this blog post to remind me…© Rick Strahl, West Wind Technologies, 2005-2011Posted in IIS7  Windows  

  Read the article

• Flash Actionscript 3.0 Game Projectile Creation

  - by Christian Basar

  I have been creating a side-scrolling Actionscript 3.0 game. In this game I want the Player to be able to shoot blow darts as weapons. I had some trouble getting the darts to be created in the right place (in front of the player), but eventually got it working with some help from this page (please look at it for background information on this problem): http://stackoverflow.com/questions/8031553/flash-actionscript-3-0-game-projectile-creation I got the darts to be created in the right place (near the player) and a 'movePlayerDarts()' function moves them. But I actually have a new problem. When the player moves after firing a dart, the dart tries to follow him! If the player jumps, the dart rises up. If the player moves to the left, the dart moves slightly to the left. Obviously, there is some code somewhere which is telling the darts to follow the player. I do not see how, unless the 'playerDartContainer' has something to do with that. But the container is always at position (0,0) and it does not move. Also, as a test I traced a dart's 'y' coordinate within the constantly-running 'movePlayerDarts()' function. As you can see, that function constantly moves the dart down the y axis by increasing its y-coordinate value. But when I jump, the 'y' coordinate being traced is never reduced, even though the dart clearly looks like it's rising! If anybody has any suggestions, I'd appreciate them! Here is the code I use to create the darts: // This function creates a dart public function createDart():void { if (playerDartContainer.numChildren <= 4) { // Play dart shooting sound sndDartShootIns.play(); // Create a new 'PlayerDart' object playerDart = new PlayerDart(); // Set the new dart's initial position and direction depending on the player's direction // Player's facing right if (player.scaleX == 1) { // Create dart in front of player's dart gun playerDart.x = player.x + 12; playerDart.y = player.y - 85; // Dart faces right, too playerDart.scaleX = 1; } // Player's facing left else if (player.scaleX == -1) { // Create dart in front of player's dart gun playerDart.x = player.x - 12; playerDart.y = player.y - 85; // Dart faces left, too playerDart.scaleX = -1; } playerDartContainer.addChild(playerDart); } } // End of 'createDart()' function This code is the EnterFrameHandler for the player darts: // In every frame, call 'movePlayerDarts()' to move the darts within the 'playerDartContainer' public function playerDartEnterFrameHandler(event:Event):void { // Only move the Player's darts if their container has at least one dart within if (playerDartContainer.numChildren > 0) { movePlayerDarts(); } } And finally, this is the code that actually moves all of the player's darts: // Move all of the Player's darts public function movePlayerDarts():void { for (var pdIns:int = 0; pdIns < playerDartContainer.numChildren; pdIns++) { // Set the Player Dart 'instance' variable to equal the current PlayerDart playerDartIns = PlayerDart(playerDartContainer.getChildAt(pdIns)); // Move the current dart in the direction it was shot. The dart's 'x-scale' // factor is multiplied by its speed (5) to move the dart in its correct // direction. If the 'x-scale' factor is -1, the dart is pointing left (as // seen in the 'createDart()' function. (-1 * 5 = -5), so the dart will go // to left at a rate of 5. The opposite is true for the right-ward facing // darts playerDartIns.x += playerDartIns.scaleX * 1; // Make gravity work on the dart playerDartIns.y += 0.7; //playerDartIns.y += 1; // What if the dart hits the ground? if (HitTest.intersects(playerDartIns, floor, this)) { playerDartContainer.removeChild(playerDartIns); } //trace("Dart x: " + playerDartIns.x); trace("Dart y: " + playerDartIns.y); } }

  Read the article

• IE9 Beta

  - by Daniel Moth

  I've been using Internet Explorer 8 since the early pre-release bits, but I never tried IE9 until today – the day the Beta is available. I downloaded it from here: http://www.beautyoftheweb.com/ The download took longer than what I expected, but I was doing other stuff, so no bother. After coming down, it asked me to reboot my computer. Really hate when apps do that, but I did it anyway. The first time I launched it, it prompted me with a list of add-ons I should disable including the start-up time that I could save fore each one. It even let me configure the prompt so, for example, it won't prompt me again unless an add-on contributes to more than 1 second of the startup time. Cool. First thing I noticed is that the search bar had gone and, as you'd expect, you have to search from the address box. I totally despise this feature. The first thing I've been doing with all versions of IE is to turn off the automatic searching from the address bar and now I have no way of searching if I do that. Ridiculous. The second thing I notice is that the tabs are next to the address bar and cannot be moved to go below it. One word for that decision: appalling (and, no, I didn't accidentally drop an 'e' and added an 'l' in the previous word). The third thing I notice to the right is the favorites button (star icon) and when I click on it, it brings up the favorites explorer under it on the right; then I pin the explorer and it jumps to the left(!). Why move the entry point to this feature to the right instead of leaving it on the left is beyond me (other than wanting to retrain me on what I've been used to for all this time), but the fact that pinning it makes it jump sides is… an "astonishing" design decision. As I browse I notice a little annoying pop up in the bottom left every time I hover over a link; there is no status bar. I correctly guessed to right click at the top and turn on the status bar (which also got rid of the popup thereafter) and while I am at it, I bring back my favorites bar which was hidden by default (and am pleased to see that all my favorites are still there). The next thing I notice, I like: IE9 is fast. No joke, I visit sites and they seem to be loading visibly much faster – try it! Beyond the speed, I am interested to find out what else is new. I searched and found a few good links: What's new in Internet Explorer 9 Internet Explorer 9 Features (check out the links under "Clean") Top Features If you are a developer, check out IE's msdn home for many articles, e.g. this section on Canvas and SVG. Either way: wherever you are, get IE9 Beta now and judge for yourself. If you don't like it, you can always uninstall (which auto-restores the previous version). Comments about this post welcome at the original blog.

  Read the article

• UPK Hands-on Labs at OHUG

  - by Karen Rihs

  Going to OHUG, June 18-22? Be sure to attend one or more UPK hands-on labs! Choose from Basic, Advanced, What's New, and Prebuilt Content!   Oracle User Productivity Kit 11.1 Workshop – Basic Stephen Armbruster, Oracle Corporation June 19, 2012, 11:00 a.m. – 12:00 p.m. June 20, 2012, 4:30 – 5:30 p.m. The User Productivity Kit (UPK) is a comprehensive, cost-effective, customizable solution that helps your organization quickly create the critical documentation, training, and support materials needed to drive project team and user productivity throughout the lifecycle of your software. The User Productivity Kit provides system process documentation, user acceptance test scripts, comprehensive instructor-led training materials, web-based training materials, role-based performance support, and complete documentation. Also provided is the UPK Developer, which serves as a single-source development and customization tool to enable rapid content creation and customization. The User Productivity Kit delivers: Business process documentation for fit-gap analysis - providing time and cost savings that jump-start your implementation or upgrade User Acceptance test scripts to help test applications prior to go-live State-of-the-art instructional design tools to rapidly build and tailor documentation, instructor-led training materials, and web-based training to fit organizational needs Live-application performance support with transactional and procedural information to maximize user efficiency. By registering for this hands-on UPK workshop, participants will use UPK to build an application job aid and simulation that can be used as performance support for the application. But hurry, space is limited! Oracle User Productivity Kit 11.1 Workshop – Advanced Stephen Armbruster, Oracle Corporation June 20, 2012, 1:30 – 2:30 p.m. This special workshop is for those already familiar with UPK and will cover advanced concepts. In this workshop, you will gain an in-depth knowledge of working with the UPK Developer. Following this workshop, you will be able to: Create publishing categories Add a logo to a publishing project Publish using the newly created category Configure your own library view Manage topic history in a multi-user environment Oracle User Productivity Kit 11.1 Workshop – What’s NEW! Stephen Armbruster, Oracle Corporation June 19, 2012, 1:30 – 2:30 p.m. June 21, 2012, 1:00 – 2:00 p.m. This special workshop is for those already familiar with UPK and will focus on the new features included in the latest version 11.1. In this workshop, you will review most of the new features included in the UPK Developer. Oracle User Productivity Kit 11.1 Workshop – Prebuilt Content Stephen Armbruster, Oracle Corporation June 19, 2012, 4:30 – 5:30 p.m. June 21, 2012, 2:15 – 3:15 p.m. This special workshop is for those already familiar with UPK and will focus on the latest version 11.1. At the end of this workshop, you will be able to demonstrate how to: Import prebuilt content Modify content frames Add a decision frame Translate a topic into Spanish Stephen Armbruster is a principal sales consultant, specializing in HCM and UPK applications for Oracle over the past twelve years. In addition to his current role, he serves as an ambassador for the Fusion User Experience (UX) team and is tasked with evangelizing the UX for end users across all Oracle brands (Fusion, PSFT, JDE, and EBS).  He is also a trusted advisor to Oracle’s Product Management teams related to Learning Management Systems (LMS). Prior to joining Oracle, he was an instructor as well as an instructional technologist working in the medical diagnostics, high tech, and information management industries. As an expert in both LMS and UPK, he regularly speaks at Oracle conferences including Oracle OpenWorld and OHUG on topics that span using Oracle solutions to accomplish employee training, certification, and user adoption. His presentations are both entertaining and engaging.

  Read the article

• T-SQL in Chicago – the LobsterPot teams with DataEducation

  - by Rob Farley

  In May, I’ll be in the US. I have board meetings for PASS at the SQLRally event in Dallas, and then I’m going to be spending a bit of time in Chicago. The big news is that while I’m in Chicago (May 14-16), I’m going to teach my “Advanced T-SQL Querying and Reporting: Building Effectiveness” course. This is a course that I’ve been teaching since the 2005 days, and have modified over time for 2008 and 2012. It’s very much my most popular course, and I love teaching it. Let me tell you why. For years, I wrote queries and thought I was good at it. I was a developer. I’d written a lot of C (and other, more fun languages like Prolog and Lisp) at university, and then got into the ‘real world’ and coded in VB, PL/SQL, and so on through to C#, and saw SQL (whichever database system it was) as just a way of getting the data back. I could write a query to return just about whatever data I wanted, and that was good. I was better at it than the people around me, and that helped. (It didn’t help my progression into management, then it just became a frustration, but for the most part, it was good to know that I was good at this particular thing.) But then I discovered the other side of querying – the execution plan. I started to learn about the translation from what I’d written into the plan, and this impacted my query-writing significantly. I look back at the queries I wrote before I understood this, and shudder. I wrote queries that were correct, but often a long way from effective. I’d done query tuning, but had largely done it without considering the plan, just inferring what indexes would help. This is not a performance-tuning course. It’s focused on the T-SQL that you read and write. But performance is a significant and recurring theme. Effective T-SQL has to be about performance – it’s the biggest way that a query becomes effective. There are other aspects too though – such as using constructs better. For example – I can write code that modifies data nicely, but if I haven’t learned about the MERGE statement and the way that it can impact things, I’m missing a few tricks. If you’re going to do this course, a good place to be is the situation I was in a few years before I wrote this course. You’re probably comfortable with writing T-SQL queries. You know how to make a SELECT statement do what you need it to, but feel there has to be a better way. You can write JOINs easily, and understand how to use LEFT JOIN to make sure you don’t filter out rows from the first table, but you’re coding blind. The first module I cover is on Query Execution. Take a look at the Course Outline at Data Education’s website. The first part of the first module is on the components of a SELECT statement (where I make you think harder about GROUP BY than you probably have before), but then we jump straight into Execution Plans. Some stuff on indexes is in there too, as is simplification and SARGability. Some of this is stuff that you may have heard me present on at conferences, but here you have me for three days straight. I’m sure you can imagine that we revisit these topics throughout the rest of the course as well, and you’d be right. In the second and third modules we look at a bunch of other aspects, including some of the T-SQL constructs that lots of people don’t know, and various other things that can help your T-SQL be, well, more effective. I’ve had quite a lot of people do this course and be itching to get back to work even on the first day. That’s not a comment about the jokes I tell, but because people want to look at the queries they run. LobsterPot Solutions is thrilled to be partnering with Data Education to bring this training to Chicago. Visit their website to register for the course. @rob_farley

  Read the article

• Difficulties with rotation of a sprite

  - by Johnny

  I want to program a dolphin that jumps and rotates like a real dolphin. Jumping is not the problem, but I don't know how to make the rotation. At the moment, my dolphin rotates a little weird. But I want that it rotates like a real dolphin does. How can I improve the rotation? public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; Texture2D image, water; float Gravity = 5.0F; float Acceleration = 20.0F; Vector2 Position = new Vector2(1200,720); Vector2 Velocity; float rotation = 0; SpriteEffects flip; Vector2 Speed = new Vector2(0, 0); public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; graphics.PreferredBackBufferWidth = 1280; graphics.PreferredBackBufferHeight = 720; } protected override void Initialize() { base.Initialize(); } protected override void LoadContent() { spriteBatch = new SpriteBatch(GraphicsDevice); image = Content.Load<Texture2D>("cartoondolphin"); water = Content.Load<Texture2D>("background"); flip = SpriteEffects.None; } protected override void Update(GameTime gameTime) { float VelocityX = 0f; float VelocityY = 0f; float time = (float)gameTime.ElapsedGameTime.TotalSeconds; KeyboardState kbState = Keyboard.GetState(); if(kbState.IsKeyDown(Keys.Left)) { rotation = 0; flip = SpriteEffects.None; VelocityX += -5f; } if(kbState.IsKeyDown(Keys.Right)) { rotation = 0; flip = SpriteEffects.FlipHorizontally; VelocityX += 5f; } // jump if the dolphin is under water if(Position.Y >= 670) { if (kbState.IsKeyDown(Keys.A)) { if (flip == SpriteEffects.None) { rotation += 0.01f; VelocityY += 40f; } else { rotation -= 0.01f; VelocityY += 40f; } } } else { if (flip == SpriteEffects.None) { rotation -= 0.01f; VelocityY += -10f; } else { rotation += 0.01f; VelocityY += -10f; } } float deltaY = 0; float deltaX = 0; deltaY = Gravity * (float)gameTime.ElapsedGameTime.TotalSeconds; deltaX += VelocityX * (float)gameTime.ElapsedGameTime.TotalSeconds * Acceleration; deltaY += -VelocityY * (float)gameTime.ElapsedGameTime.TotalSeconds * Acceleration; Speed = new Vector2(Speed.X + deltaX, Speed.Y + deltaY); Position += Speed * (float)gameTime.ElapsedGameTime.TotalSeconds; Velocity.X = 0; if (Position.Y + image.Height/2 > graphics.PreferredBackBufferHeight) Position.Y = graphics.PreferredBackBufferHeight - image.Height/2; base.Update(gameTime); } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); spriteBatch.Begin(); spriteBatch.Draw(water, new Rectangle(0, graphics.PreferredBackBufferHeight -100, graphics.PreferredBackBufferWidth, 100), Color.White); spriteBatch.Draw(image, Position, null, Color.White, rotation, new Vector2(image.Width / 2, image.Height / 2), 1, flip, 1); spriteBatch.End(); base.Draw(gameTime); } }

  Read the article

• Free RAM disappears - Memory leak?

  - by Izzy

  On a fresh started system, free reports about 1.5G used RAM (8G RAM alltogether, Ubuntu 12.04 with lightdm and plasma desktop, one konsole window started). Having the apps running I use, it still consumes not more than 2G. However, having the system running for a couple of days, more and more of my free RAM disappears -- without showing up in the list of used apps: while smem --pie=name reports less than 20% used (and 80% being available), everything else says differently. free -m for example reports on about day 7: total used free shared buffers cached Mem: 7459 7013 446 0 178 997 -/+ buffers/cache: 5836 1623 Swap: 9536 296 9240 (so you can see, it's not the buffers or the cache). Today this finally ended with the system crashing completely: the windows manager being gone, apps "hanging in the air" (frameless) -- and a popup notifying me about "too many open files". Syslog reports: kernel: [856738.020829] VFS: file-max limit 752838 reached So I closed those applications I was able to close, and killed X using Ctrl-Alt-backspace. X tried to come up again after that with failsafeX, but was unable to do so as it could no longer detect its configuration. So I switched to a console using Ctrl-Alt-F2, captured all information I could think of (vmstat, free, smem, proc/meminfo, lsof, ps aux), and finally rebooted. X again came up with failsafeX; this time I told it to "recover from my backed-up configuration", then switched to a console and successfully used startx to bring up the graphical environment. I have no real clue to what is causing this issue -- though it must have to do either with X itself, or with some user processes running on X -- as after killing X, free -m output looked like this: total used free shared buffers cached Mem: 7459 2677 4781 0 62 419 -/+ buffers/cache: 2195 5263 Swap: 9536 59 9477 (~3.5GB being freed) -- to compare with the output after a fresh start: total used free shared buffers cached Mem: 7459 1483 5975 0 63 730 -/+ buffers/cache: 689 6769 Swap: 9536 0 9536 Two more helpful outputs are provided by memstat -u. Shortly before the crash: User Count Swap USS PSS RSS mail 1 0 200 207 616 whoopsie 1 764 740 817 2300 colord 1 3200 836 894 2156 root 62 70404 352996 382260 569920 izzy 80 177508 1465416 1519266 1851840 After having X killed: User Count Swap USS PSS RSS mail 1 0 184 188 356 izzy 1 1400 708 739 1080 whoopsie 1 848 668 826 1772 colord 1 3204 804 888 1728 root 62 54876 131708 149950 267860 And after a restart, back in X: User Count Swap USS PSS RSS mail 1 0 212 217 628 whoopsie 1 0 1536 1880 5096 colord 1 0 3740 4217 7936 root 54 0 148668 180911 345132 izzy 47 0 370928 437562 915056 Edit: Just added two graphs from my monitoring system. Interesting to see: everytime when there's a "jump" in memory consumption, CPU peaks as well. Just found this right now -- and it reminds me of another indicator pointing to X itself: Often when returning to my machine and unlocking the screen, I found something doing heavvy work on my CPU. Checking with top, it always turned out to be /usr/bin/X :0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch -background none. So after this long explanation, finally my questions: What could be the possible causes? How can I better identify involved processes/applications? What steps could be taken to avoid this behaviour -- short from rebooting the machine all X days? I was running 8.04 (Hardy) for about 5 years on my old machine, never having experienced the like (always more than 100 days uptime, before rebooting for e.g. kernel updates). This now is a complete new machine with a fresh install of 8.04. In case it matters, some specs: AMD A4-3400 APU with Radeon(tm) HD Graphics, using the open-source ati/radeon driver (so no fglrx installed), 8GB RAM, WDC WD1002FAEX-0 hdd (1TB), Asus F1A75-V Evo mainboard. Ubuntu 12.04 64-bit with KDE4/Plasma. Apps usually open more or less permanently include Evolution, Firefox, konsole (with Midnight Commander running inside, about 4 tabs), and LibreOffice -- plus occasionally Calibre, Gimp and Moneyplex (banking software I'm already using for almost 20 years now, in a version which did fine on Hardy).

  Read the article

• Professional Developers, may I join you?

  - by Ben

  I currently work in technical support for a software/hardware company and for the most part it's a good job, but it's feeling more and more like I'm getting 'stuck' here. No raises in the 5 years I've been here, and lately there seems to be more hiring from the outside than promotion from within. The work I do is more technical than end-user support, as we deal primarily with our field technicians who have a little more technical skill than the general user base. As a result I get into much more technical support issues... often tracking down bugs in our software, finding performance bottlenecks in our database schema, etc. The work I'm most proud of are the development projects I've come up with on my own, and worked on during lunch breaks and slow periods in Support. Over the years I've written a number of useful utilities for the company. Diagnostic type applications that several departments use and appreciate. These include apps that simulate our various hardware devices, log file analysis, time-saving utilities for our work processes, etc. My best projects have been the hardware simulation programs, which are the type of thing we probably wouldn't have put a full-time developer on had anyone thought to do it, but they've ended up being popular and useful enough to be used by development, QA, R&D, and Support. They allow us to interface our software with simulated hardware, rather than clutter up our work areas with bulky, hard to acquire equipment. Since starting here my life has moved forward (married, kid, one more on the way), but it feels like my career has not. I still earn what I earned walking in the door my first day. Company budget is tight, bonuses have gone down, and no raises or cost of living / inflation adjustments either. As the sole source of income for my family I feel I need to do more, and I'd like to have a more active role in creating something at work, not just cleaning up other people's mistakes. I enjoy technical work, and I think development is the next logical step in my career. I'd like to bring some "legitimacy" to my part-time development work, and make myself a more skilled and valuable employee. Ultimately if this can help me better support my family, that would be ideal. Can I make the jump to professional developer? I have an engineering degree, but no formal education in computer science. I write WinForms apps using the .NET framework, do some freelance web development, have volunteered to write software for a nonprofit, and have started experimenting with programming microcontrollers. I enjoy learning new things in the limited free time I have available. I think I have the aptitude to take on a development role, even in an 'apprentice' capacity if such an option is possible. Have any of you moved into development like this? Do any of you developers have any advice or cautionary tales? Are there better career options I haven't thought of? I welcome any and all related comments and thank you in advance for posting them.

  Read the article

• Subterranean IL: Compiling C# exception handlers

  - by Simon Cooper

  An exception handler in C# combines the IL catch and finally exception handling clauses into a single try statement: try { Console.WriteLine("Try block") // ... } catch (IOException) { Console.WriteLine("IOException catch") // ... } catch (Exception e) { Console.WriteLine("Exception catch") // ... } finally { Console.WriteLine("Finally block") // ... } How does this get compiled into IL? Initial implementation If you remember from my earlier post, finally clauses must be specified with their own .try clause. So, for the initial implementation, we take the try/catch/finally, and simply split it up into two .try clauses (I have to use label syntax for this): StartTry: ldstr "Try block" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End EndTry: StartIOECatch: ldstr "IOException catch" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End EndIOECatch: StartECatch: ldstr "Exception catch" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End EndECatch: StartFinally: ldstr "Finally block" call void [mscorlib]System.Console::WriteLine(string) // ... endfinally EndFinally: End: // ... .try StartTry to EndTry catch [mscorlib]System.IO.IOException handler StartIOECatch to EndIOECatch catch [mscorlib]System.Exception handler StartECatch to EndECatch .try StartTry to EndTry finally handler StartFinally to EndFinally However, the resulting program isn't verifiable, and doesn't run: [IL]: Error: Shared try has finally or fault handler. Nested try blocks What's with the verification error? Well, it's a condition of IL verification that all exception handling regions (try, catch, filter, finally, fault) of a single .try clause have to be completely contained within any outer exception region, and they can't overlap with any other exception handling clause. In other words, IL exception handling clauses must to be representable in the scoped syntax, and in this example, we're overlapping catch and finally clauses. Not only is this example not verifiable, it isn't semantically correct. The finally handler is specified round the .try. What happens if you were able to run this code, and an exception was thrown? Program execution enters top of try block, and exception is thrown within it CLR searches for an exception handler, finds catch Because control flow is leaving .try, finally block is run The catch block is run leave.s End inside the catch handler branches to End label. We're actually running the finally before the catch! What we do about it What we actually need to do is put the catch clauses inside the finally clause, as this will ensure the finally gets executed at the correct time (this time using scoped syntax): .try { .try { ldstr "Try block" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End } catch [mscorlib]System.IO.IOException { ldstr "IOException catch" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End } catch [mscorlib]System.Exception { ldstr "Exception catch" call void [mscorlib]System.Console::WriteLine(string) // ... leave.s End } } finally { ldstr "Finally block" call void [mscorlib]System.Console::WriteLine(string) // ... endfinally } End: ret Returning from methods There is a further semantic mismatch that the C# compiler has to deal with; in C#, you are allowed to return from within an exception handling block: public int HandleMethod() { try { // ... return 0; } catch (Exception) { // ... return -1; } } However, you can't ret inside an exception handling block in IL. So the C# compiler does a leave.s to a ret outside the exception handling area, loading/storing any return value to a local variable along the way (as leave.s clears the stack): .method public instance int32 HandleMethod() { .locals init ( int32 retVal ) .try { // ... ldc.i4.0 stloc.0 leave.s End } catch [mscorlib]System.Exception { // ... ldc.i4.m1 stloc.0 leave.s End } End: ldloc.0 ret } Conclusion As you can see, the C# compiler has quite a few hoops to jump through to translate C# code into semantically-correct IL, and hides the numerous conditions on IL exception handling blocks from the C# programmer. Next up: catch-all blocks, and how the runtime deals with non-Exception exceptions.

  Read the article

• #OOW 2012: Big Data and The Social Revolution

  - by Eric Bezille

  As what was saying Cognizant CSO Malcolm Frank about the "Futur of Work", and how the Business should prepare in the face of the new generation  not only of devices and "internet of things" but also due to their users ("The Millennials"), moving from "consumers" to "prosumers" :  we are at a turning point today which is bringing us to the next IT Architecture Wave. So this is no more just about putting Big Data, Social Networks and Customer Experience (CxM) on top of old existing processes, it is about embracing the next curve, by identifying what processes need to be improve, but also and more importantly what processes are obsolete and need to be get ride of, and new processes put in place. It is about managing both the hierarchical and structured Enterprise and its social connections and influencers inside and outside of the Enterprise. And this does apply everywhere, up to the Utilities and Smart Grids, where it is no more just about delivering (faster) the same old 300 reports that have grown over time with those new technologies but to understand what need to be looked at, in real-time, down to an hand full relevant reports with the KPI relevant to the business. It is about how IT can anticipate the next wave, and is able to answers Business questions, and give those capabilities in real-time right at the hand of the decision makers... This is the turning curve, where IT is really moving from the past decade "Cost Center" to "Value for the Business", as Corporate Stakeholders will be able to touch the value directly at the tip of their fingers. It is all about making Data Driven Strategic decisions, encompassed and enriched by ALL the Data, and connected to customers/prosumers influencers. This brings to stakeholders the ability to make informed decisions on question like : “What would be the best Olympic Gold winner to represent my automotive brand ?”... in a few clicks and in real-time, based on social media analysis (twitter, Facebook, Google+...) and connections link to my Enterprise data. A true example demonstrated by Larry Ellison in real-time during his yesterday’s key notes, where “Hardware and Software Engineered to Work Together” is not only about extreme performances but also solutions that Business can touch thanks to well integrated Customer eXperience Management and Social Networking : bringing the capabilities to IT to move to the IT Architecture Next wave. An example, illustrated also todays in 2 others sessions, that I had the opportunity to attend. The first session bringing the “Internet of Things” in Oil&Gaz into actionable decisions thanks to Complex Event Processing capturing sensors data with the ready to run IT infrastructure leveraging Exalogic for the CEP side, Exadata for the enrich datasets and Exalytics to provide the informed decision interface up to end-user. The second session showing Real Time Decision engine in action for ACCOR hotels, with Eric Wyttynck, VP eCommerce, and his Technical Director Pascal Massenet. I have to close my post here, as I have to go to run our practical hands-on lab, cooked with Olivier Canonge, Christophe Pauliat and Simon Coter, illustrating in practice the Oracle Infrastructure Private Cloud recently announced last Sunday by Larry, and developed through many examples this morning by John Folwer. John also announced today Solaris 11.1 with a range of network innovation and virtualization at the OS level, as well as many optimizations for applications, like for Oracle RAC, with the introduction of the lock manager inside Solaris Kernel. Last but not least, he introduced Xsigo Datacenter Fabric for highly simplified networks and storage virtualization for your Cloud Infrastructure. Hoping you will get ready to jump on the next wave, we are here to help...

  Read the article

• Best depth sorting method for a Top Down 2D game using a 3D physics engine

  - by Alic44

  I've spent many days googling this and still have issues with my game engine I'd like to ask about, which I haven't seen addressed before. I think the problem is that my game is an unusual combination of a completely 2D graphical approach using XNA's SpriteBatch, and a completely 3D engine (the amazing BEPU physics engine) with rotation mostly disabled. In essence, my question is similar to this one (the part about "faux 3D"), but the difference is that in my game, the player as well as every other creature is represented by 3D objects, and they can all jump, pick up other objects, and throw them around. What this means is that sorting by one value, such as a Z position (how far north/south a character is on the screen) won't work, because as soon as a smaller creature jumps on top of a larger creature, or a box, and walks backwards, the moment its z value is less than that other creature, it will appear to be behind the object it is actually standing on. I actually originally solved this problem by splitting every object in the game into physics boxes which MUST have a Y height equal to their Z depth. I then based the depth sorting value on the object's y position (how high it is off the ground) PLUS its z position (how far north or south it is on the screen). The problem with this approach is that it requires all moving objects in the game to be split graphically into chunks which match up with a physical box which has its y dimension equal to its z dimension. Which is stupid. So, I got inspired last night to rewrite with a fresh approach. My new method is a little more complex, but I think a little more sane: every object which needs to be sorted by depth in the game exposes the interface IDepthDrawable and is added to a list owned by the DepthDrawer object. IDepthDrawable contains: public interface IDepthDrawable { Rectangle Bounds { get; } //possibly change this to a class if struct copying of the xna Rectangle type becomes an issue DepthDrawShape DepthShape { get; } void Draw(SpriteBatch spriteBatch); } The Bounds Rectangle of each IDepthDrawable object represents the 2D Axis-Aligned Bounding Box it will take up when drawn to the screen. Anything that doesn't intersect the screen will be culled at this stage and the remaining on-screen IDepthDrawables will be Bounds tested for intersections with each other. This is where I get a little less sure of what I'm doing. Each group of collisions will be added to a list or other collection, and each list will sort itself based on its DepthShape property, which will have access to the object-to-be-drawn's physics information. For starting out, lets assume everything in the game is an axis aligned 3D Box shape. Boxes are pretty easy to sort. Something like: if (depthShape1.Back > depthShape2.Front) //if depthShape1 is in front of depthShape2. //depthShape1 goes on top. else if (depthShape1.Bottom > depthShape2.Top) //if depthShape1 is above depthShape2. //depthShape1 goes on top. //if neither of these are true, depthShape2 must be in front or above. So, by sorting draw order by several different factors from the physics engine, I believe I can get a really correct draw order. My question is, is this a good way of going about this, or is there some tried and true, tested way which is completely different and has somehow completely eluded me on the internets? And, if this does seem like a good way to remake my draw order sorting, what's the right sorting algorithm for reordering the Bounds Rectangle collision lists, and how do you deal with a Bounds Rectangle colliding with two different object which don't collide with eachother. I know these are solved problems, but I've only been programming for a year so any specific input here will be greatly appreciated. Thanks for reading this far, ye who made it -- sorry it was so long!

  Read the article

• Improving the running time of Breadth First Search and Adjacency List creation

  - by user45957

  We are given an array of integers where all elements are between 0-9. have to start from the 1st position and reach end in minimum no of moves such that we can from an index i move 1 position back and forward i.e i-1 and i+1 and jump to any index having the same value as index i. Time Limit : 1 second Max input size : 100000 I have tried to solve this problem use a single source shortest path approach using Breadth First Search and though BFS itself is O(V+E) and runs in time the adjacency list creation takes O(n2) time and therefore overall complexity becomes O(n2). is there any way i can decrease the time complexity of adjacency list creation? or is there a better and more efficient way of solving the problem? int main(){ vector<int> v; string str; vector<int> sets[10]; cin>>str; int in; for(int i=0;i<str.length();i++){ in=str[i]-'0'; v.push_back(in); sets[in].push_back(i); } int n=v.size(); if(n==1){ cout<<"0\n"; return 0; } if(v[0]==v[n-1]){ cout<<"1\n"; return 0; } vector<int> adj[100001]; for(int i=0;i<10;i++){ for(int j=0;j<sets[i].size();j++){ if(sets[i][j]>0) adj[sets[i][j]].push_back(sets[i][j]-1); if(sets[i][j]<n-1) adj[sets[i][j]].push_back(sets[i][j]+1); for(int k=j+1;k<sets[i].size();k++){ if(abs(sets[i][j]-sets[i][k])!=1){ adj[sets[i][j]].push_back(sets[i][k]); adj[sets[i][k]].push_back(sets[i][j]); } } } } queue<int> q; q.push(0); int dist[100001]; bool visited[100001]={false}; dist[0]=0; visited[0]=true; int c=0; while(!q.empty()){ int dq=q.front(); q.pop(); c++; for(int i=0;i<adj[dq].size();i++){ if(visited[adj[dq][i]]==false){ dist[adj[dq][i]]=dist[dq]+1; visited[adj[dq][i]]=true; q.push(adj[dq][i]); } } } cout<<dist[n-1]<<"\n"; return 0; }

  Read the article

• Is Cloud Security Holding Back Social SaaS?

  - by Mike Stiles

  The true promise of social data co-mingling with enterprise data to influence and inform social marketing (all marketing really) lives in cloud computing. The cloud brings processing power, services, speed and cost savings the likes of which few organizations could ever put into action on their own. So why wouldn’t anyone jump into SaaS (Software as a Service) with both feet? Cloud security. Being concerned about security is proper and healthy. That just means you’re a responsible operator. Whether it’s protecting your customers’ data or trying to stay off the radar of regulatory agencies, you have plenty of reasons to make sure you’re as protected from hacking, theft and loss as you can possibly be. But you also have plenty of reasons to not let security concerns freeze you in your tracks, preventing you from innovating, moving the socially-enabled enterprise forward, and keeping up with competitors who may not be as skittish regarding SaaS technology adoption. Over half of organizations are transferring sensitive or confidential data to the cloud, an increase of 10% over last year. With the roles and responsibilities of CMO’s, CIO’s and other C’s changing, the first thing you should probably determine is who should take point on analyzing cloud software options, providers, and policies. An oft-quoted Ponemon Institute study found 36% of businesses don’t have a cloud security policy at all. So that’s as good a place to start as any. What applications and data are you comfortable housing in the cloud? Do you have a classification system for data that clearly spells out where data types can go and how they can be used? Who, both internally and at the cloud provider, will function as admins? What are the different levels of admin clearance? Will your security policies and procedures sync up with those of your cloud provider? The key is verifiable trust. Trust in cloud security is actually going up. 1/3 of organizations polled say it’s the cloud provider who should be responsible for data protection. And when you look specifically at SaaS providers, that expectation goes up to 60%. 57% “strongly agree” or “agree” there’s more confidence in cloud providers’ ability to protect data. In fact, some businesses bypass the “verifiable” part of verifiable trust. Just over half have no idea what their cloud provider does to protect data. And yet, according to the “Private Cloud Vision vs. Reality” InformationWeek Report, 82% of organizations say security/data privacy are one of the main reasons they’re still holding the public cloud at arm’s length. That’s going to be a tough position to maintain, because just as social is rapidly changing the face of marketing, big data is rapidly changing the face of enterprise IT. Netflix, who’s particularly big on the benefits of the cloud, says, "We're systematically disassembling the corporate IT components." An enterprise can never realize the full power of big data, nor get the full potential value out of it, if it’s unwilling to enable the integrations and dataset connections necessary in the cloud. Because integration is called for to reduce fragmentation, a standardized platform makes a lot of sense. With multiple components crafted to work together, you’re maximizing scalability, optimization, cost effectiveness, and yes security and identity management benefits. You can see how the incentive is there for cloud companies to develop and add ever-improving security features, making cloud computing an eventual far safer bet than traditional IT. @mikestilesPhoto: stock.xchng

  Read the article

• What's wrong with this turn to face algorithm?

  - by Chan

  I implement a torpedo object that chases a rotating planet. Specifically, it will turn toward the planet each update. Initially my implement was: void move() { vector3<float> to_target = target - get_position(); to_target.normalize(); position += (to_target * speed); } which works perfectly for torpedo that is a solid sphere. Now my torpedo is actually a model, which has a forward vector, so using this method looks odd because it doesn't actually turn toward but jump toward. So I revised it a bit to get, double get_rotation_angle(vector3<float> u, vector3<float> v) const { u.normalize(); v.normalize(); double cosine_theta = u.dot(v); // domain of arccosine is [-1, 1] if (cosine_theta > 1) { cosine_theta = 1; } if (cosine_theta < -1) { cosine_theta = -1; } return math3d::to_degree(acos(cosine_theta)); } vector3<float> get_rotation_axis(vector3<float> u, vector3<float> v) const { u.normalize(); v.normalize(); // fix linear case if (u == v || u == -v) { v[0] += 0.05; v[1] += 0.0; v[2] += 0.05; v.normalize(); } vector3<float> axis = u.cross(v); return axis.normal(); } void turn_to_face() { vector3<float> to_target = (target - position); vector3<float> axis = get_rotation_axis(get_forward(), to_target); double angle = get_rotation_angle(get_forward(), to_target); double distance = math3d::distance(position, target); gl_matrix_mode(GL_MODELVIEW); gl_push_matrix(); { gl_load_identity(); gl_translate_f(position.get_x(), position.get_y(), position.get_z()); gl_rotate_f(angle, axis.get_x(), axis.get_y(), axis.get_z()); gl_get_float_v(GL_MODELVIEW_MATRIX, OM); } gl_pop_matrix(); move(); } void move() { vector3<float> to_target = target - get_position(); to_target.normalize(); position += (get_forward() * speed); } The logic is simple, I find the rotation axis by cross product, the angle to rotate by dot product, then turn toward the target position each update. Unfortunately, it looks extremely odds since the rotation happens too fast that it always turns back and forth. The forward vector for torpedo is from the ModelView matrix, the third column A: MODELVIEW MATRIX -------------------------------------------------- R U A T -------------------------------------------------- 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 -------------------------------------------------- Any suggestion or idea would be greatly appreciated.

  Read the article

• Grid pathfinding with a lot of entities

  - by Vee

  I'd like to explain this problem with a screenshot from a released game, DROD: Gunthro's Epic Blunder, by Caravel Games. The game is turn-based and tile-based. I'm trying to create something very similar (a clone of the game), and I've got most of the fundamentals done, but I'm having trouble implementing pathfinding. Look at the screenshot. The guys in yellow are friendly, and want to kill the roaches. Every turn, every guy in yellow pathfinds to the closest roach, and every roach pathfinds to the closest guy in yellow. By closest I mean the target with the shortest path, not a simple distance calculation. All of this without any kind of slowdown when loading the level or when passing turns. And all of the entities change position every turn. Also (not shown in screenshot), there can be doors that open and close and change the level's layout. Impressive. I've tried implementing pathfinding in my clone. First attempt was making every roach find a path to a yellow guy every turn, using a breadth-first search algorithm. Obviously incredibly slow with more than a single roach, and would get exponentially slower with more than a single yellow guy. Second attempt was mas making every yellow guy generate a pathmap (still breadth-first search) every time he moved. Worked perfectly with multiple roaches and a single yellow guy, but adding more yellow guys made the game slow and unplayable. Last attempt was implementing JPS (jump point search). Every entity would individually calculate a path to its target. Fast, but with a limited number of entities. Having less than half the entities in the screenshot would make the game slow. And also, I had to get the "closest" enemy by calculating distance, not shortest path. I've asked on the DROD forums how they did it, and a user replied that it was breadth-first search. The game is open source, and I took a look at the source code, but it's C++ (I'm using C#) and I found it confusing. I don't know how to do it. Every approach I tried isn't good enough. And I believe that DROD generates global pathmaps, somehow, but I can't understand how every entity find the best individual path to other entities that move every turn. What's the trick? This is a reply I just got on the DROD forums: Without having looked at the code I'd wager it's two (or so) pathmaps for the whole room: One to the nearest enemy, and one to the nearest friendly for every tile. There's no need to make a separate pathmap for every entity when the overall goal is "move towards nearest enemy/friendly"... just mark every tile with the number of moves it takes to the nearest target and have the entity chose the move that takes it to the tile with the lowest number. To be honest, I don't understand it that well.

  Read the article

• Is It Worth It To Learn Experimental Languages

  - by Xander Lamkins

  I'm a young programmer who desires to work in the field someday as a programmer. I know Java, VB.NET and C#. I want to learn a new language (as I programmer, I know that it is valuable to extend what I know - to learn languages that make you think differently). I took a look online to see what languages were common. Everybody knows C and C++ (even those muggles who know so little about computers in general), so I thought, maybe I should push for C. C and C++ are nice but they are old. Things like Haskell and Forth (etc. etc. etc.) are old and have lost their popularity. I'm scared of learning C (or even C++) for this same reason. Java is pretty old as well and is slow because it's run by the JVM and not compiled to native code. I've been a Windows developer for quite a while. I recently started using Java - but only because it was more versatile and spreadable to other places. The problem is that it doesn't look like a very usable language for these reasons: It's most used purpose is for web application and cellphone apps (specifically Android) As far as actual products made with it, the only things that come to mind are Netbeans, Eclipse (hurrah for making and IDE with the language the IDE is for - it's like making a webpage for writing HTML/CSS/Javascript), and Minecraft which happens to be fun but laggy and bipolar as far as computer spec. support. Other than that it's used for servers but heck - I don't only want to make/configure servers. The .NET languages are nice, however: People laugh if I even mention VB.NET or C# in a serious conversation. It isn't cross-platform unless you use MONO (which is still in development and has some improvements to be made). Lacks low level stuff because, like Java with the JVM, it is run/managed by the CLR. My first thought was learning something like C and then using it to springboard into C++ (just to make sure I would have a strong understanding/base), but like I said earlier, it's getting older and older by the minute. What I've Looked Into Fantom looks nice. It's like a nice middleman between my two favorite languages and even lets me publish between the two interchangeably, but, unlike what I want, it compiles to the CLR or JVM (depending on what you publish it to) instead of it being a complete compile. D also looks nice. It seems like a very usable language and from multiple sources it appears to actually be better than C/C++. I would jump right with it, but I'm still unsure of its success because it obviously isn't very mainstream at this point. There are a couple others that looked pretty nice that focused on other things such as Opa with web development and Go by GOOGLE. My Question Is it worth learning these "experimental" languages? I've read other questions that say that if you aren't constantly learning languages and open to all languages that you aren't in the right mindset for programming. I understand this and I still might not quite be getting it, but in truth, if a language isn't going to become mainstream, should I spend my time learning something else? I don't want to learn old (or any going to soon be old) programming languages. I know that many people see this as something important, *but would any of you ever actually consider (assuming you didn't already know) FORTRAN? My goal is to stay current to make sure I'm successful in the future. Disclaimer Yes, I am a young programmer, so I probably made a lot of naive statements in my question. Feel free to correct me on ANYTHING! I have to start learning somewhere so I'm sure a lot of my knowledge is sketchy enough to have caused to incorrect statements or flaws in my thinking. Please leave any feelings you have in the comments.

  Read the article

• Platform jumping problems with AABB collisions

  - by Vee

  See the diagram first: When my AABB physics engine resolves an intersection, it does so by finding the axis where the penetration is smaller, then "push out" the entity on that axis. Considering the "jumping moving left" example: If velocityX is bigger than velocityY, AABB pushes the entity out on the Y axis, effectively stopping the jump (result: the player stops in mid-air). If velocityX is smaller than velocitY (not shown in diagram), the program works as intended, because AABB pushes the entity out on the X axis. How can I solve this problem? Source code: public void Update() { Position += Velocity; Velocity += World.Gravity; List<SSSPBody> toCheck = World.SpatialHash.GetNearbyItems(this); for (int i = 0; i < toCheck.Count; i++) { SSSPBody body = toCheck[i]; body.Test.Color = Color.White; if (body != this && body.Static) { float left = (body.CornerMin.X - CornerMax.X); float right = (body.CornerMax.X - CornerMin.X); float top = (body.CornerMin.Y - CornerMax.Y); float bottom = (body.CornerMax.Y - CornerMin.Y); if (SSSPUtils.AABBIsOverlapping(this, body)) { body.Test.Color = Color.Yellow; Vector2 overlapVector = SSSPUtils.AABBGetOverlapVector(left, right, top, bottom); Position += overlapVector; } if (SSSPUtils.AABBIsCollidingTop(this, body)) { if ((Position.X >= body.CornerMin.X && Position.X <= body.CornerMax.X) && (Position.Y + Height/2f == body.Position.Y - body.Height/2f)) { body.Test.Color = Color.Red; Velocity = new Vector2(Velocity.X, 0); } } } } } public static bool AABBIsOverlapping(SSSPBody mBody1, SSSPBody mBody2) { if(mBody1.CornerMax.X <= mBody2.CornerMin.X || mBody1.CornerMin.X >= mBody2.CornerMax.X) return false; if (mBody1.CornerMax.Y <= mBody2.CornerMin.Y || mBody1.CornerMin.Y >= mBody2.CornerMax.Y) return false; return true; } public static bool AABBIsColliding(SSSPBody mBody1, SSSPBody mBody2) { if (mBody1.CornerMax.X < mBody2.CornerMin.X || mBody1.CornerMin.X > mBody2.CornerMax.X) return false; if (mBody1.CornerMax.Y < mBody2.CornerMin.Y || mBody1.CornerMin.Y > mBody2.CornerMax.Y) return false; return true; } public static bool AABBIsCollidingTop(SSSPBody mBody1, SSSPBody mBody2) { if (mBody1.CornerMax.X < mBody2.CornerMin.X || mBody1.CornerMin.X > mBody2.CornerMax.X) return false; if (mBody1.CornerMax.Y < mBody2.CornerMin.Y || mBody1.CornerMin.Y > mBody2.CornerMax.Y) return false; if(mBody1.CornerMax.Y == mBody2.CornerMin.Y) return true; return false; } public static Vector2 AABBGetOverlapVector(float mLeft, float mRight, float mTop, float mBottom) { Vector2 result = new Vector2(0, 0); if ((mLeft > 0 || mRight < 0) || (mTop > 0 || mBottom < 0)) return result; if (Math.Abs(mLeft) < mRight) result.X = mLeft; else result.X = mRight; if (Math.Abs(mTop) < mBottom) result.Y = mTop; else result.Y = mBottom; if (Math.Abs(result.X) < Math.Abs(result.Y)) result.Y = 0; else result.X = 0; return result; }

  Read the article

• Is it worth to learn Experimental Languages?

  - by Xander Lamkins

  I'm a young programmer who desires to work in the field someday as a programmer. I know Java, VB.NET and C#. I want to learn a new language (as I programmer, I know that it is valuable to extend what I know - to learn languages that make you think differently). I took a look online to see what languages were common. Everybody knows C and C++ (even those muggles who know so little about computers in general), so I thought, maybe I should push for C. C and C++ are nice but they are old. Things like Haskell and Forth (etc. etc. etc.) are old and have lost their popularity. I'm scared of learning C (or even C++) for this same reason. Java is pretty old as well and is slow because it's run by the JVM and not compiled to native code. I've been a Windows developer for quite a while. I recently started using Java - but only because it was more versatile and spreadable to other places. The problem is that it doesn't look like a very usable language for these reasons: It's most used purpose is for web application and cellphone apps (specifically Android) As far as actual products made with it, the only things that come to mind are Netbeans, Eclipse (hurrah for making and IDE with the language the IDE is for - it's like making a webpage for writing HTML/CSS/Javascript), and Minecraft which happens to be fun but laggy and bipolar as far as computer spec. support. Other than that it's used for servers but heck - I don't only want to make/configure servers. The .NET languages are nice, however: People laugh if I even mention VB.NET or C# in a serious conversation. It isn't cross-platform unless you use MONO (which is still in development and has some improvements to be made). Lacks low level stuff because, like Java with the JVM, it is run/managed by the CLR. My first thought was learning something like C and then using it to springboard into C++ (just to make sure I would have a strong understanding/base), but like I said earlier, it's getting older and older by the minute. What I've Looked Into Fantom looks nice. It's like a nice middleman between my two favorite languages and even lets me publish between the two interchangeably, but, unlike what I want, it compiles to the CLR or JVM (depending on what you publish it to) instead of it being a complete compile. D also looks nice. It seems like a very usable language and from multiple sources it appears to actually be better than C/C++. I would jump right with it, but I'm still unsure of its success because it obviously isn't very mainstream at this point. There are a couple others that looked pretty nice that focused on other things such as Opa with web development and Go by GOOGLE. My Question Is it worth learning these "experimental" languages? I've read other questions that say that if you aren't constantly learning languages and open to all languages that you aren't in the right mindset for programming. I understand this and I still might not quite be getting it, but in truth, if a language isn't going to become mainstream, should I spend my time learning something else? I don't want to learn old (or any going to soon be old) programming languages. I know that many people see this as something important, *but would any of you ever actually consider (assuming you didn't already know) FORTRAN? My goal is to stay current to make sure I'm successful in the future. Disclaimer Yes, I am a young programmer, so I probably made a lot of naive statements in my question. Feel free to correct me on ANYTHING! I have to start learning somewhere so I'm sure a lot of my knowledge is sketchy enough to have caused to incorrect statements or flaws in my thinking. Please leave any feelings you have in the comments.

  Read the article

• Asynchrony in C# 5 (Part I)

  - by javarg

  I’ve been playing around with the new Async CTP preview available for download from Microsoft. It’s amazing how language trends are influencing the evolution of Microsoft’s developing platform. Much effort is being done at language level today than previous versions of .NET. In these post series I’ll review some major features contained in this release: Asynchronous functions TPL Dataflow Task based asynchronous Pattern Part I: Asynchronous Functions This is a mean of expressing asynchronous operations. This kind of functions must return void or Task/Task<> (functions returning void let us implement Fire & Forget asynchronous operations). The two new keywords introduced are async and await. async: marks a function as asynchronous, indicating that some part of its execution may take place some time later (after the method call has returned). Thus, all async functions must include some kind of asynchronous operations. This keyword on its own does not make a function asynchronous thought, its nature depends on its implementation. await: allows us to define operations inside a function that will be awaited for continuation (more on this later). Async function sample: Async/Await Sample async void ShowDateTimeAsync() {     while (true)     {         var client = new ServiceReference1.Service1Client();         var dt = await client.GetDateTimeTaskAsync();         Console.WriteLine("Current DateTime is: {0}", dt);         await TaskEx.Delay(1000);     } } The previous sample is a typical usage scenario for these new features. Suppose we query some external Web Service to get data (in this case the current DateTime) and we do so at regular intervals in order to refresh user’s UI. Note the async and await functions working together. The ShowDateTimeAsync method indicate its asynchronous nature to the caller using the keyword async (that it may complete after returning control to its caller). The await keyword indicates the flow control of the method will continue executing asynchronously after client.GetDateTimeTaskAsync returns. The latter is the most important thing to understand about the behavior of this method and how this actually works. The flow control of the method will be reconstructed after any asynchronous operation completes (specified with the keyword await). This reconstruction of flow control is the real magic behind the scene and it is done by C#/VB compilers. Note how we didn’t use any of the regular existing async patterns and we’ve defined the method very much like a synchronous one. Now, compare the following code snippet  in contrast to the previuous async/await: Traditional UI Async void ComplicatedShowDateTime() {     var client = new ServiceReference1.Service1Client();     client.GetDateTimeCompleted += (s, e) =>     {         Console.WriteLine("Current DateTime is: {0}", e.Result);         client.GetDateTimeAsync();     };     client.GetDateTimeAsync(); } The previous implementation is somehow similar to the first shown, but more complicated. Note how the while loop is implemented as a chained callback to the same method (client.GetDateTimeAsync) inside the event handler (please, do not do this in your own application, this is just an example).  How it works? Using an state workflow (or jump table actually), the compiler expands our code and create the necessary steps to execute it, resuming pending operations after any asynchronous one. The intention of the new Async/Await pattern is to let us think and code as we normally do when designing and algorithm. It also allows us to preserve the logical flow control of the program (without using any tricky coding patterns to accomplish this). The compiler will then create the necessary workflow to execute operations as the happen in time.

  Read the article

• My 2D collision code does not work as expected. How do I fix it?

  - by farmdve

  I have a simple 2D game with a tile-based map. I am new to game development, I followed the LazyFoo tutorials on SDL. The tiles are in a bmp file, but each tile inside it corresponds to an internal number of the type of tile(color, or wall). The game is simple, but the code is a lot so I can only post snippets. // Player moved out of the map if((player.box.x < 0)) player.box.x += GetVelocity(player, 0); if((player.box.y < 0)) player.box.y += GetVelocity(player, 1); if((player.box.x > (LEVEL_WIDTH - DOT_WIDTH))) player.box.x -= GetVelocity(player, 0); if((player.box.y > (LEVEL_HEIGHT - DOT_HEIGHT))) player.box.y -= GetVelocity(player, 1); // Now that we are here, we check for collisions if(touches_wall(player.box)) { if(player.box.x < player.prev_x) { player.box.x += GetVelocity(player, 0); } if(player.box.x > player.prev_x) { player.box.x -= GetVelocity(player, 0); } if(player.box.y < player.prev_y) { player.box.y += GetVelocity(player, 1); } if(player.box.y > player.prev_y) { player.box.y -= GetVelocity(player, 1); } } player.prev_x = player.box.x; player.prev_y = player.box.y; Let me explain, player is a structure with the following contents typedef struct { Rectangle box; //Player position on a map(tile or whatever). int prev_x, prev_y; // Previous positions int key_press[3]; // Stores which key was pressed/released. Limited to three keys. E.g Left,right and perhaps jump if possible in 2D int velX, velY; // Velocity for X and Y coordinate. //Health int health; bool main_character; uint32_t jump_ticks; } Player; And Rectangle is just a typedef of SDL_Rect. GetVelocity is a function that according to the second argument, returns the velocity for the X or Y axis. This code I have basically works, however inside the if(touches_wall(player.box)) if statement, I have 4 more. These 4 if statements are responsible for detecting collision on all 4 sides(up,down,left,right). However, they also act as a block for any other movement. Example: I move down the object and collide with the wall, as I continue to move down and still collide with the wall, I wish to move left or right, which is indeed possible(not to mention in 3D games), but remember the 4 if statements? They are preventing me from moving anywhere. The original code on the LazyFoo Productions website has no problems, but it was written in C++, so I had to rewrite most of it to work, which is probably where the problem comes from. I also use a different method of moving, than the one in the examples. Of course, that was just an example. I wish to be able to move no matter at which wall I collide. Before this bit of code, I had another one that had more logic in there, but it was flawed.

  Read the article

• The Rise of Project Intelligence and Why It Matters

  - by Melissa Centurio Lopes

  Normal 0 false false false EN-US 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:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; 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;} By Amy DeWolf Are you doing any of these in your organization? How are you leveraging historical data to forecast projects? There’s a lot going on in government today. The economic pressures agencies feel from the uncertainty of budget cuts and sequestration effect every part of an organization, including the Project Management Office (PMO).  The PMO is responsible for monitoring and administering government IT projects. As time goes on, priorities shift, technology advances, and new regulations are imposed, all of which make planning and executing projects more difficult.  For example, think about your own projects.  How many boxes do you need to check and hoops do you need to jump through to ensure you comply with new regulations? While new regulations and technology advancements can be a good thing, they add an additional layer of complexity to already complex projects. To overcome some of these pressures, particularly new regulations, many in the PMO world are adopting a new approach- Project Intelligence (PI). According to a new Oracle Primavera white paper, The Rise of Project Intelligence: When Project Management is Just Not Enough, “PI uses Business Intelligence methods to leverage historical project data to make more informed decisions and greatly enhance project execution.” Currently, project managers plan and forecast the possible phases in an execution cycle.  However, most project managers don’t have the proper tools to do this as effectively as they would like. As the white paper noted, “The underlying deficiencies in most forecasting approaches are that 1) the PM fails in most instances to leverage historical data and 2) the PM doesn’t employ current Business Intelligence tools.” PI seeks to overturn this by combining modeling tools used in Business Intelligence for projects with the understanding of Emotional Intelligence for managing people.   Simply put, Project Intelligence is built off four main pillars: Actively use historical data to forecast project cycles Understand the intricacies of complex projects Enhance social and emotional intelligence in projects Actively use Business intelligence tools Read our complimentary whitepaper and discover the importance of emotional intelligence and best practices for improving projects, specifically in terms of communication.

  Read the article

• The Future of Air Travel: Intelligence and Automation

  - by BobEvans

  Remember those white-knuckle flights through stormy weather where unexpected plunges in altitude result in near-permanent relocations of major internal organs? Perhaps there’s a better way, according to a recent Wall Street Journal article: “Pilots of a Honeywell International Inc. test plane stayed on their initial flight path, relying on the company's latest onboard radar technology to steer through the worst of the weather. The specially outfitted Boeing 757 barely shuddered as it gingerly skirted some of the most ferocious storm cells over Fort Walton Beach and then climbed above the rest in zero visibility.” Or how about the multifaceted check-in process, which might not wreak havoc on liver location but nevertheless makes you wonder if you’ve been trapped in some sort of covert psychological-stress test? Another WSJ article, called “The Self-Service Airport,” says there’s reason for hope there as well: “Airlines are laying the groundwork for the next big step in the airport experience: a trip from the curb to the plane without interacting with a single airline employee. At the airport of the near future, ‘your first interaction could be with a flight attendant,’ said Ben Minicucci, chief operating officer of Alaska Airlines, a unit of Alaska Air Group Inc.” And in the topsy-turvy world of air travel, it’s not just the passengers who’ve been experiencing bumpy rides: the airlines themselves are grappling with a range of challenges—some beyond their control, some not—that make profitability increasingly elusive in spite of heavy demand for their services. A recent piece in The Economist illustrates one of the mega-challenges confronting the airline industry via a striking set of contrasting and very large numbers: while the airlines pay $7 billion per year to third-party computerized reservation services, the airlines themselves earn a collective profit of only $3 billion per year. In that context, the anecdotes above point unmistakably to the future that airlines must pursue if they hope to be able to manage some of the factors outside of their control (e.g., weather) as well as all of those within their control (operating expenses, end-to-end visibility, safety, load optimization, etc.): more intelligence, more automation, more interconnectedness, and more real-time awareness of every facet of their operations. Those moves will benefit both passengers and the air carriers, says the WSJ piece on The Self-Service Airport: “Airlines say the advanced technology will quicken the airport experience for seasoned travelers—shaving a minute or two from the checked-baggage process alone—while freeing airline employees to focus on fliers with questions. ‘It's more about throughput with the resources you have than getting rid of humans,’ said Andrew O'Connor, director of airport solutions at Geneva-based airline IT provider SITA.” Oracle’s attempting to help airlines gain control over these challenges by blending together a range of its technologies into a solution called the Oracle Airline Data Model, which suggests the following steps: • To retain and grow their customer base, airlines need to focus on the customer experience. • To personalize and differentiate the customer experience, airlines need to effectively manage their passenger data. • The Oracle Airline Data Model can help airlines jump-start their customer-experience initiatives by consolidating passenger data into a customer data hub that drives realtime business intelligence and strategic customer insight. • Oracle’s Airline Data Model brings together multiple types of data that can jumpstart your data-warehousing project with rich out-of-the-box functionality. • Oracle’s Intelligent Warehouse for Airlines brings together the powerful capabilities of Oracle Exadata and the Oracle Airline Data Model to give you real-time strategic insights into passenger demand, revenues, sales channels and your flight network. The airline industry aside, the bullet points above offer a broad strategic outline for just about any industry because the customer experience is becoming pre-eminent in each and there is simply no way to deliver world-class customer experiences unless a company can capture, manage, and analyze all of the relevant data in real-time. I’ll leave you with two thoughts from the WSJ article about the new in-flight radar system from Honeywell: first, studies show that a single episode of serious turbulence can wrack up $150,000 in additional costs for an airline—so, it certainly behooves the carriers to gain the intelligence to avoid turbulence as much as possible. And second, it’s back to that top-priority customer-experience thing and the value that ever-increasing levels of intelligence can deliver. As the article says: “In the cabin, reporters watched screens showing the most intense parts of the nearly 10-mile wide storm, which churned some 7,000 feet below, in vibrant red and other colors. The screens also were filled with tiny symbols depicting likely locations of lightning and hail, which can damage planes and wreak havoc on the nerves of white-knuckle flyers.”  (Bob Evans is senior vice-president, communications, for Oracle.)  

  Read the article

• Numerically stable(ish) method of getting Y-intercept of mouse position?

  - by Fraser

  I'm trying to unproject the mouse position to get the position on the X-Z plane of a ray cast from the mouse. The camera is fully controllable by the user. Right now, the algorithm I'm using is... Unproject the mouse into the camera to get the ray: Vector3 p1 = Vector3.Unproject(new Vector3(x, y, 0), 0, 0, width, height, nearPlane, farPlane, viewProj; Vector3 p2 = Vector3.Unproject(new Vector3(x, y, 1), 0, 0, width, height, nearPlane, farPlane, viewProj); Vector3 dir = p2 - p1; dir.Normalize(); Ray ray = Ray(p1, dir); Then get the Y-intercept by using algebra: float t = -ray.Position.Y / ray.Direction.Y; Vector3 p = ray.Position + t * ray.Direction; The problem is that the projected position is "jumpy". As I make small adjustments to the mouse position, the projected point moves in strange ways. For example, if I move the mouse one pixel up, it will sometimes move the projected position down, but when I move it a second pixel, the project position will jump back to the mouse's location. The projected location is always close to where it should be, but it does not smoothly follow a moving mouse. The problem intensifies as I zoom the camera out. I believe the problem is caused by numeric instability. I can make minor improvements to this by doing some computations at double precision, and possibly abusing the fact that floating point calculations are done at 80-bit precision on x86, however before I start micro-optimizing this and getting deep into how the CLR handles floating point, I was wondering if there's an algorithmic change I can do to improve this? EDIT: A little snooping around in .NET Reflector on SlimDX.dll: public static Vector3 Unproject(Vector3 vector, float x, float y, float width, float height, float minZ, float maxZ, Matrix worldViewProjection) { Vector3 coordinate = new Vector3(); Matrix result = new Matrix(); Matrix.Invert(ref worldViewProjection, out result); coordinate.X = (float) ((((vector.X - x) / ((double) width)) * 2.0) - 1.0); coordinate.Y = (float) -((((vector.Y - y) / ((double) height)) * 2.0) - 1.0); coordinate.Z = (vector.Z - minZ) / (maxZ - minZ); TransformCoordinate(ref coordinate, ref result, out coordinate); return coordinate; } // ... public static void TransformCoordinate(ref Vector3 coordinate, ref Matrix transformation, out Vector3 result) { Vector3 vector; Vector4 vector2 = new Vector4 { X = (((coordinate.Y * transformation.M21) + (coordinate.X * transformation.M11)) + (coordinate.Z * transformation.M31)) + transformation.M41, Y = (((coordinate.Y * transformation.M22) + (coordinate.X * transformation.M12)) + (coordinate.Z * transformation.M32)) + transformation.M42, Z = (((coordinate.Y * transformation.M23) + (coordinate.X * transformation.M13)) + (coordinate.Z * transformation.M33)) + transformation.M43 }; float num = (float) (1.0 / ((((transformation.M24 * coordinate.Y) + (transformation.M14 * coordinate.X)) + (coordinate.Z * transformation.M34)) + transformation.M44)); vector2.W = num; vector.X = vector2.X * num; vector.Y = vector2.Y * num; vector.Z = vector2.Z * num; result = vector; } ...which seems to be a pretty standard method of unprojecting a point from a projection matrix, however this serves to introduce another point of possible instability. Still, I'd like to stick with the SlimDX Unproject routine rather than writing my own unless it's really necessary.

  Read the article

• Introducing the Oracle Linux Playground yum repo

  - by wcoekaer

  We just introduced a new yum repository/channel on http://public-yum.oracle.com called the playground channel. What we started doing is the following: When a new stable mainline kernel is released by Linus or GregKH, we internally build RPMs to test it and do some QA work around it to keep track of what's going on with the latest development kernels. It helps us understand how performance moves up or down and if there are issues, we try to help look into them and of course send that stuff back upstream. Many Linux users out there are interested in trying out the latest features but there are some potential barriers to do this. (1) in general, you are looking at an upstream development distribution, which means that everything changes both in userspace(random applications) and kernel. Projects like Fedora are very useful and someone that wants to just see how the entire distribution evolves with all the changes, this is a great way to be current. A drawback here, though, is that if you have applications that are not part of the distribution, there's a lot of manual work involved or they might just not work because the changes are too drastic. The introduction of systemd is a good example. (2) when you look at many of our customers, that are interested in our database products or applications, the starting point of having a supported/certified userspace/distribution, like Oracle Linux, is a much easier way to get your feet wet in seeing what new/future Linux kernel enhancements could do. This is where the playground channel comes into play. When you install Oracle Linux 6 (which anyone can download and use from http://edelivery.oracle.com/linux), grab the latest public yum repository file http://public-yum.oracle.com/public-yum-ol6.repo, put it in /etc/yum.repos.d and enable the playground repo : [ol6_playground_latest] name=Latest mainline stable kernel for Oracle Linux 6 ($basearch) - Unsupported baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/playground/latest/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=1 Now, all you need to do : type yum update and you will be downloading the latest stable kernel which will install cleanly on Oracle Linux 6. Thus you end up with a stable Linux distribution where you can install all your software, and then download the latest stable kernel (at time of writing this is 3.6.7) without having to recompile a kernel, without having to jump through hoops. There is of course a big, very important disclaimer this is NOT for PRODUCTION use. We want to try and help make it easy for people that are interested, from a user perspective, where the Linux kernel is going and make it easy to install and use it and play around with new features. Without having to learn how to compile a kernel and without necessarily having to install a complete new distribution with all the changes top to bottom. So we don't or won't introduce any new userspace changes, this project really is around making it easy to try out the latest upstream Linux kernels in a very easy way on an environment that's stable and you can keep current, since all the latest errata for Oracle Linux 6 are published on the public yum repo as well. So one repository location for all your current changes and the upstream kernels. We hope that this will get more users to try out the latest kernel and report their findings. We are always interested in understanding stability and performance characteristics. As new features are going into the mainline kernel, that could potentially be interesting or useful for various products, we will try to point them out on our blogs and give an example on how something can be used so you can try it out for yourselves. Anyway, I hope people will find this useful and that it will help increase interested in upstream development beyond reading lkml by some of the more non-kernel-developer types.

  Read the article

• Passed: Exam 70-480: Programming in HTML5 with JavaScript and CSS3

  First off: Mission accomplished successfully. And it was fun! Using the resources listed in my previous article about Learning Content, I'd like to thank Microsoft Technical Evangelists Jeremy Foster and Michael Palermo for their excellent jump start videos on Channel 9, and the various authors at Pluralsight. Local Prometric testing centre Back in November I chose a local testing centre which was the easiest to access from my office despite the horrible traffic you might experience here on the island. Actually, it was not the closest one. But due to their website, their awards as Microsoft Learning Center, and my general curiosity about the premises, I gave FRCI my priority. Boy, how should I regret this decision this morning... The official Prometric exam guide asks any attendee to show up at least 30 minutes prior to the scheduled time of the test. Well, this should have been the easier part but unfortunately due to heavier traffic than usual I arrived only 20 minutes before time. Not too bad but more to come. The building called 'le Hub' is nicely renovated and provides the right environment for an IT group of companies like FRCI. I think they have currently 5 independent IT departments over there. Even the handling at the reception was straight forward, welcoming and at my ease. But then... first shock: "We don't have any exam registration for today." - Hm, that's nice... Here's my mail confirmation from Prometric. First attack successfully handled and the lady went off again to check their records. Next shock: A couple of minutes later, another guy tries to explain me that "the staff of the testing centre is already on vacation and the centre is officially closed." - Are you kidding me? Here's the official confirmation by Prometric, and I don't find it funny that I take a day off today only to hear this kind of blubbering nonsense. I thought that I'll be on the safe side choosing a company with a good reputation here on the island. Another 40 (!) minutes later, they finally come back to the waiting area with a pre-filled form about the test appointment. And finally, after an hour of waiting, discussing, restarting the testing PC, and lots of talk, I am allowed to sit down and take the exam. Exam details Well, you know the rules. Signing an NDA doesn't allow me to provide you any details about the questions or topics that have been covered. Please check out the official exam description, and you're on the right way. Sorry, guys... ;-) The result "Congratulations! You have passed this Microsoft Certification exam." - In general, I have to admit that the parts on HTML5 and CSS3 were the easiest after all, and that I have to get myself a little bit more familiar with certain Javascript features like class definitions, inheritance and data security. Anyway, exam passed - who cares about the details? Next goal Of course, the journey to Microsoft Certifications continues and my next goal is to pass exams 70-481 - Essentials of Developing Windows Store Apps using HTML5 and JavaScript and 70-482 - Advanced Windows Store App Development using HTML5 and JavaScript. This would allow me to achieve the certification of MCSD: Windows Store Apps using HTML5. I guess, during 2013 I'll be busy with various learning and teaching lessons.

  Read the article

< Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >