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• Runtime polymorphism in c#

  In this article I will write the code first about the classes and explain you later how its achieved in c#.

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• F# and the useful infinite Sequence (I think)

  - by MarkPearl

  So I have seen a few posts done by other F# fans on solving project Euler problems. They looked really interesting and I thought with my limited knowledge of F# I would attempt a few and the first one I had a look at was problem 5. Which said : “2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. What is the smallest number that is evenly divisible by all of the numbers from 1 to 20?” So I jumped into coding it and straight away got stuck – the C# programmer in me wants to do a loop, starting at one and dividing every number by 1 to 20 to see if they all divide and once a match is found, there is your solution. Obviously not the most elegant way but a good old brute force approach. However I am pretty sure this would not be the F# way…. So after a bit of research I found the Sequences and how useful they were. Sequences seemed like the beginning of an approach to solve my problem. In my head I thought - create a sequence, and then start at the beginning of it and move through it till you find a value that is divisible by 1 to 20. Sounds reasonable? So the question is begged - how would you create a sequence that you are sure will be large enough to hold the solution to the problem? Well… You can’t know! Some more googling and I found what I would call infinite sequences – something that looks like this… let nums = 1 |> Seq.unfold (fun i -> Some (i, i + 1))   My interpretation of this would be as follows… create a sequence, and whenever it is called add 1 to its size (I would appreciate someone helping me on wording this right functionally). Something that I don’t understand fully yet is the forward pipe operator (|>) which I think plays a key role in this code. With this in hand I was able to code a basic optimized solution to this problem. I’m going to go over it some more before I post the full code just in case!

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• How to do proper Alpha in XNA?

  - by Soshimo

  Okay, I've read several articles, tutorials, and questions regarding this. Most point to the same technique which doesn't solve my problem. I need the ability to create semi-transparent sprites (texture2D's really) and have them overlay another sprite. I can achieve that somewhat with the code samples I've found but I'm not satisfied with the results and I know there is a way to do this. In mobile programming (BREW) we did it old school and actually checked each pixel for transparency before rendering. In this case it seems to render the sprite below it blended with the alpha above it. This may be an artifact of how I'm rendering the texture but, as I said before, all examples point to this one technique. Before I go any further I'll go ahead and paste my example code. public void Draw(SpriteBatch batch, Camera camera, float alpha) { int tileMapWidth = Width; int tileMapHeight = Height; batch.Begin(SpriteSortMode.Texture, BlendState.AlphaBlend, SamplerState.PointWrap, DepthStencilState.Default, RasterizerState.CullNone, null, camera.TransformMatrix); for (int x = 0; x < tileMapWidth; x++) { for (int y = 0; y < tileMapHeight; y++) { int tileIndex = _map[y, x]; if (tileIndex != -1) { Texture2D texture = _tileTextures[tileIndex]; batch.Draw( texture, new Rectangle( (x * Engine.TileWidth), (y * Engine.TileHeight), Engine.TileWidth, Engine.TileHeight), new Color(new Vector4(1f, 1f, 1f, alpha ))); } } } batch.End(); } As you can see, in this code I'm using the overloaded SpriteBatch.Begin method which takes, among other things, a blend state. I'm almost positive that's my problem. I don't want to BLEND the sprites, I want them to be transparent when alpha is 0. In this example I can set alpha to 0 but it still renders both tiles, with the lower z ordered sprite showing through, discolored because of the blending. This is not a desired effect, I want the higher z-ordered sprite to fade out and not effect the color beneath it in such a manner. I might be way off here as I'm fairly new to XNA development so feel free to steer me in the correct direction in the event I'm going down the wrong rabbit hole. TIA

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• How do I consolidate the differences between iOS and Android update loops?

  - by kkan

  I'm currently working on moving some Android-ndk code to the iPhone. From looking at some samples it seems that the main loop is handled for you and all you've got to do is override the render method on the view to handle the rendering. Then add a selector to handle the update methods. The render method itself looks like it's attached to the windows refresh. But in android I've got my own game loop that controls the rendering and updates using C++ time.h. Is it possible to implement the same here bypassing Apple's loop? I'd really like the keep the structures of the code similar.

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• Best/ most efficient way to learn a programming language as a beginner [closed]

  - by dizzytri99er

  I am a student and have obtained a one year placement at a business that develops an e-commerce system using C#, HTML, WPF, javascript, ASP and more. Although I do have a little bit of knowledge, I find myself being assigned a lot of tasks that are beyond me and even when I ask for help, the response I get is often cryptic to me. I stare at as much code as possible to just try and "throw myself into it" but I often just get lost in the code I like to consider myself a fast learner and I am damn determined to be a good programmer. I would just like to ask if there are some tips for me to catch up as quick as possible? I don't want to be a nuisance and sit here and ask for help 24/7. I just want to crack on!

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• Is it dangerous for me to give some of my Model classes Control-like methods?

  - by Pureferret

  In my personal project I have tried to stick to MVC, but I've also been made aware that sticking to MVC too tightly can be a bad thing as it makes writing awkward and forces the flow of the program in odd ways (i.e. some simple functions can be performed by something that normally wouldn't, and avoid MVC related overheads). So I'm beginning to feel justified in this compromise: I have some 'manager programs' that 'own' data and have some way to manipulate it, as such I think they'd count as both part of the model, and part of the control, and to me this feels more natural than keepingthem separate. For instance: One of my Managers is the PlayerCharacterManager that has these methods: void buySkill(PlayerCharacter playerCharacter, Skill skill); void changeName(); void changeRole(); void restatCharacter(); void addCharacterToGame(); void createNewCharacter(); PlayerCharacter getPlayerCharacter(); List<PlayerCharacter> getPlayersCharacter(Player player); List<PlayerCharacter> getAllCharacters(); I hope the mothod names are transparent enough that they don't all need explaining. I've called it a manager because it will help manage all of the PlayerCharacter 'model' objects the code creates, and create and keep a map of these. I may also get it to store other information in the future. I plan to have another two similar classes for this sort of control, but I will orchestrate when and how this happens, and what to do with the returned data via a pure controller class. This splitting up control between informed managers and the controller, as opposed to operating just through a controller seems like it will simplify my code and make it flow more. My question is, is this a dangerous choice, in terms of making the code harder to follow/test/fix? Is this somethign established as good or bad or neutral? I oculdn't find anything similar except the idea of Actors but that's not quite why I'm trying to do. Edit: Perhaps an example is needed; I'm using the Controller to update the view and access the data, so when I click the 'Add new character to a player button' it'll call methods in the controller that then go and tell the PlayerCharacterManager class to create a new character instance, it'll call the PlayerManager class to add that new character to the player-character map, and then it'll add this information to the database, and tell the view to update any GUIs effected. That is the sort of 'control sequence' I'm hoping to create with these manager classes.

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• Navigation for ASP.NET Web Forms project published on codeplex

  Navigation for ASP.NET Web Forms manages movement and data passing between aspx Pages in a unit testable manner. There is no Client-side logic, so it works in all browsers, and no Server-side cache, so it works with the browser back button.Features include loosely coupled Pages, typed data passing, empty code-behinds, context-sensitive bread crumb trail, ASP.NET Data binding integration, automatic ASP.NET Ajax history navigation and many more.The source code, binaries and comprehensive documentation...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Writing scripts for Visual Studio project

  - by oillio

  What is the best way to write and run small scripts and tasks that are specific to a particular .Net project? Such things as configuring a database or confirming proper connections to servers. In Ruby, I would build rake tasks for this sort of thing. I am currently using unit tests for these tasks as they are easy to run within VS and they have access to all the necessary libraries and project code. However, this is not really their intended purpose and, with the dropping of Test Lists in VS 2012, it does not work nearly as well as it used to. Is there a better solution than writing a console project to handle these little code snippets I need to run periodically?

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• How to program a cutting tool for 3D model in game

  - by Jesse S

  I'm looking for a resource to figure out how to program a function to cut a 3d model in game. Example: Enemy/NPC is sliced into 2 pieces with a sword. His body is not hollow, you can see bloody texture where normally a 'polygon hole' would be. The first step is to actually 'cut/slice' the model, then add in polygons to fill the hole in the model. I know this can be done in 3D modelling software, but I'm not sure how to go about doing this in a game, code-wise. I do not wish to use 'pre cut-up" models, the code will determine where the cut is. Any pointers in the right direction would be greatly appreciated.

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• calling methods if previous call success

  - by New Developer

  I my c# program I have to perform 5 steps(tasks) sequentially. basically these five should execute one after the other only the previous task performed is success. Currently I have done it in following style. But this is not very good code style to follow. var isSuccess=false; isSuccess=a.method1(); if(isSuccess) isSuccess=a.method2(); if(isSuccess) isSuccess=a.method3(); if(isSuccess) isSuccess=a.method4(); if(isSuccess) isSuccess=a.method5(); How can I re factor this code. What is the best way I can follow?

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• Multi-threaded JOGL Problem

  - by moeabdol

  I'm writing a simple OpenGL application in Java that implements the Monte Carlo method for estimating the value of PI. The method is pretty easy. Simply, you draw a circle inside a unit square and then plot random points over the scene. Now, for each point that is inside the circle you increment the counter for in points. After determining for all the random points wither they are inside the circle or not you divide the number of in points over the total number of points you have plotted all multiplied by 4 to get an estimation of PI. It goes something like this PI = (inPoints / totalPoints) * 4. This is because mathematically the ratio of a circle's area to a square's area is PI/4, so when we multiply it by 4 we get PI. My problem doesn't lie in the algorithm itself; however, I'm having problems trying to plot the points as they are being generated instead of just plotting everything at once when the program finishes executing. I want to give the application a sense of real-time display where the user would see the points as they are being plotted. I'm a beginner at OpenGL and I'm pretty sure there is a multi-threading feature built into it. Non the less, I tried to manually create my own thread. Each worker thread plots one point at a time. Following is the psudo-code: /* this part of the code exists in display() method in MyCanvas.java which extends GLCanvas and implements GLEventListener */ // main loop for(int i = 0; i < number_of_points; i++){ RandomGenerator random = new RandomGenerator(); float x = random.nextFloat(); float y = random.nextFloat(); Thread pointThread = new Thread(new PointThread(x, y)); } gl.glFlush(); /* this part of the code exists in run() method in PointThread.java which implements Runnable */ void run(){ try{ gl.glPushMatrix(); gl.glBegin(GL2.GL_POINTS); if(pointIsIn) gl.glColor3f(1.0f, 0.0f, 0.0f); // red point else gl.glColor3f(0.0f, 0.0f, 1.0f); // blue point gl.glVertex3f(x, y, 0.0f); // coordinates gl.glEnd(); gl.glPopMatrix(); }catch(Exception e){ } } I'm not sure if my approach to solving this issue is correct. I hope you guys can help me out. Thanks.

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• Control HelpButton, HelpRequested, HelpButtonClicked - Instant help for windows Dialog Form components

  Instant help for windows dialog components is a great feature and very much known since windows 98. but I saw many many people are not aware it and query on Google to get help, but “help button” for dialogs helps you or your customers to get the help instantly. Every dialog window has help icon if that dialog was coded to enable it. it really helps to know the functionality of the components quickly. For example I was trying to pint a document from acrobat reader and opened printer properties to print the content front and back of the paper. If you observe there is a help button before close button. To get help on options of “Print on Both Sides” you would need to click on help button first and then click on the area on which you want to see the help. above picture shows help text for the options of “Print on Both Sides”. If you would like to get the help using keyboard you can use F1 key. Help button can be displayed only if minimize button and maximize button both are not shown unless you want go with custom buttons. below is the way if you want to get Help button for windows forms.   In this sample demo I want to have a checkbox and need to show help when I click on F1 on check box. So I created a form which country check box and help label as show in adjacent picture. Below is the code for your code bind file. using System; using System.Windows.Forms; namespace WindowsFormsApplication1 {     public partial classForm1: Form    {         publicForm1()         {             InitializeComponent();         }         private void Form1_Load(objectsender, EventArgs e)         {             this.Text = "Help Button Demo Form";             lblHelp.Text = "Press F1 on any component to get Instant Help";             this.HelpButton = true;             this.MaximizeBox = false;             this.MinimizeBox = false;             chkCountry.Tag = "Check or Uncheck Coutry Check Box";             chkCountry.HelpRequested += newHelpEventHandler(chkCountry_HelpRequested);             chkCountry.MouseLeave += newEventHandler(chkCountry_MouseLeave);         }         void chkCountry_HelpRequested(objectsender, HelpEventArgs hlpevent)         {             ControlrequestingControl = (Control)sender;             lblHelp.Text = (string)requestingControl.Tag;             hlpevent.Handled = true;         }         void chkCountry_MouseLeave(objectsender, EventArgs e)         {             lblHelp.Text = "Press F1 on any component to get Instant Help";         }     } } In above code  “HelpRequested” is an event will be fired when you click on F1 on Country checkbox. I stored the help information in the checkbox property called “Tag”. You might also maintain a property file to keep help text for each component differently. If you click on F1 when focus is on main form instead on individual component then generally separate help window opens. This can be done using the event “Form.HelpRequested” to open help windows as in below code. this.HelpRequested += newHelpEventHandler(Form1_HelpRequested); voidForm1_HelpRequested(objectsender, HelpEventArgs hlpevent) {     frmHelp.Show(); } span.fullpost {display:none;}

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• Unity mouse input not working in webplayer build

  - by Califer

  I have a button script with the following code void OnMouseDown() { animation.Play("button-squish"); enlarged = true; audio.PlayOneShot(buttonSound); } void OnMouseUpAsButton() { if (enlarged) { SelectThisButton(); enlarged = false; animation.Play("button-return"); } } void OnMouseExit() { if (enlarged) { enlarged = false; animation.Play("button-return"); } } It works great in the editor, but when I made a build and tested it in Chrome none of the buttons had any response. Further testing revealed that it did work in Firefox. Rather than telling people to change their browser if they want to play, I want to make the button code work. How else can I get the buttons to know when they're being pressed if the built-in stuff isn't working?

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• How can I make refactoring a priority for my team?

  - by Joseph Garland

  The codebase I work with daily has no automated tests, inconsistent naming and tons of comments like "Why is this here?", "Not sure if this is needed" or "This method isn't named right" and the code is littered with "Changelogs" despite the fact we use source control. Suffice it to say, our codebase could use refactoring. We always have tasks to fix bugs or add new features, so no time is put aside to refactor code to be better and more modular, and it doesn't seem to be a high priority. How can I demonstrate the value of refactoring such that it gets added to our task lists? Is it worth it to just refactor as I go, asking for forgiveness rather than permission?

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• SEO-meta description crawling issue [duplicate]

  - by user3707382

  This question already has an answer here: Meta Descriptions not working for google search 3 answers i have following code where i m including my title and description for the page But google crawled only title not the meta description from the code. Where as meta description was read from the keywords present in html of the page.. Please guide me guys where i m coding wrongly <!DOCTYPE html> <html> <head> <title>title inserted here</title> <meta http-equiv="Content-Type" content="text/html;charset=utf-8"> <meta name="description" content="description here"/>

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• Does CSS Positioning Affect SEO [duplicate]

  - by etangins

  This question is an exact duplicate of: Make Offscreen Sliding Content Without Hurting SEO [duplicate] If I positioned the very first content that appears in my code below the fold, would that content be given less weight and therefore be less effective with SEO? In addition, if I had a large image that took up most of the top of the screen and resulting in my content being below the fold or toward the bottom of the screen, would that content be given less weight? Note This is content that occurs early on in my code. I'm not talking about having a ton of content and if the content that occurs later would be given less weight, but if content that occurs early on put ends up below the fold would be given less weight.

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• Folly : la bibliothèque C++ open-source de Facebook, une initiative pour partager les outils utilisés en interne

  Folly : la bibliothèque C++ open-source de Facebook Une initiative pour partager les outils utilisés en interne Herb Sutter, l'expert reconnu du langage C++, encense dans son dernier billet de blog l'initiative de Facebook qui vient tout juste de publier en open-source sa bibliothèque d'utilités : Folly. Cette bibliothèque contient tout un tas d'algorithmes et de structures utilisés dans le code de Facebook. L'essentiel des fonctionnalités couvre les problèmes de performances ou d'absence d'implémentations trouvés dans les bibliothèques déjà existantes comme Boost ou la bibliothèque standard. De plus en plus d'entreprises mettent leur code source à disposition de tous et permettent...

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• Adobe Air apps on the Mac App Store?

  - by coneybeare

  Before you chastise me for asking this, I have an Adobe Air app that has a lot of investment in it, and if there is a way to utilize the existing code-base in any way, it is worth considering. I have heard news reports in passing about Adobe creating some kind of tool to allow flash or air apps to be ported to native objective-c code, but the information found in google is mostly commentary on the one-time Apple blockade. My question(s) is/are this: Is it even possible, at any level, to use an existing Air app to create a Mac Store app? If possible, what are the resources I can use to accomplish this?

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• On what name should I claim copyright in open source software?

  - by ONOZ

  When I want to use the Apache 2.0 licence in my project, I should include this in the comments of my source code: Copyright [yyyy] [name of copyright owner] Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. What name should I fill in for [name of copyright owner]? I am currently working alone on this project, but I'm going to release the source code so there might be other contributors in the near future.

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• Multiple vulnerabilities in Thunderbird

  - by chandan

  CVE DescriptionCVSSv2 Base ScoreComponentProduct and Resolution CVE-2012-0451 Improper Control of Generation of Code ('Code Injection') vulnerability 4.3 Thunderbird Solaris 11 11/11 SRU 8.5 CVE-2012-0455 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability 4.3 CVE-2012-0456 Information Exposure vulnerability 5.0 CVE-2012-0457 Resource Management Errors vulnerability 9.3 CVE-2012-0458 Permissions, Privileges, and Access Controls vulnerability 6.8 CVE-2012-0459 Permissions, Privileges, and Access Controls vulnerability 7.5 CVE-2012-0460 Permissions, Privileges, and Access Controls vulnerability 6.4 CVE-2012-0461 Denial of Service (DoS) vulnerability 7.5 CVE-2012-0462 Denial of Service (DoS) vulnerability 7.5 CVE-2012-0464 Resource Management Errors vulnerability 7.5 This notification describes vulnerabilities fixed in third-party components that are included in Sun's product distribution.Information about vulnerabilities affecting Oracle Sun products can be found on Oracle Critical Patch Updates and Security Alerts page.

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• Multiple vulnerabilities in Firefox web browser

  - by chandan

  CVE DescriptionCVSSv2 Base ScoreComponentProduct and Resolution CVE-2012-0451 Improper Control of Generation of Code ('Code Injection') vulnerability 4.3 Firefox web browser Solaris 11 11/11 SRU 8.5 CVE-2012-0455 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability 4.3 CVE-2012-0456 Information Exposure vulnerability 5.0 CVE-2012-0457 Resource Management Errors vulnerability 9.3 CVE-2012-0458 Permissions, Privileges, and Access Controls vulnerability 6.8 CVE-2012-0459 Permissions, Privileges, and Access Controls vulnerability 7.5 CVE-2012-0460 Permissions, Privileges, and Access Controls vulnerability 6.4 CVE-2012-0461 Denial of Service (DoS) vulnerability 7.5 CVE-2012-0462 Denial of Service (DoS) vulnerability 7.5 CVE-2012-0464 Resource Management Errors vulnerability 7.5 This notification describes vulnerabilities fixed in third-party components that are included in Sun's product distribution.Information about vulnerabilities affecting Oracle Sun products can be found on Oracle Critical Patch Updates and Security Alerts page.

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• "Whole-team" C++ features?

  - by Blaisorblade

  In C++, features like exceptions impact your whole program: you can either disable them in your whole program, or you need to deal with them throughout your code. As a famous article on C++ Report puts it: Counter-intuitively, the hard part of coding exceptions is not the explicit throws and catches. The really hard part of using exceptions is to write all the intervening code in such a way that an arbitrary exception can propagate from its throw site to its handler, arriving safely and without damaging other parts of the program along the way. Since even new throws exceptions, every function needs to provide basic exception safety — unless it only calls functions which guarantee throwing no exception — unless you disable exceptions altogether in your whole project. Hence, exceptions are a "whole-program" or "whole-team" feature, since they must be understood by everybody in a team using them. But not all C++ features are like that, as far as I know. A possible example is that if I don't get templates but I do not use them, I will still be able to write correct C++ — or will I not?. I can even call sort on an array of integers and enjoy its amazing speed advantage wrt. C's qsort (because no function pointer is called), without risking bugs — or not? It seems templates are not "whole-team". Are there other C++ features which impact code not directly using them, and are hence "whole-team"? I am especially interested in features not present in C. Update: I'm especially looking for features where there's no language-enforced sign you need to be aware of them. The first answer I got mentioned const-correctness, which is also whole-team, hence everybody needs to learn about it; however, AFAICS it will impact you only if you call a function which is marked const, and the compiler will prevent you from calling it on non-const objects, so you get something to google for. With exceptions, you don't even get that; moreover, they're always used as soon as you use new, hence exceptions are more "insidious". Since I can't phrase this as objectively, though, I will appreciate any whole-team feature. Appendix: Why this question is objective (if you wonder) C++ is a complex language, so many projects or coding guides try to select "simple" C++ features, and many people try to include or exclude some ones according to mostly subjective criteria. Questions about that get rightfully closed regularly here on SO. Above, instead, I defined (as precisely as possible) what a "whole-team" language feature is, provide an example (exceptions), together with extensive supporting evidence in the literature about C++, and ask for whole-team features in C++ beyond exceptions. Whether you should use "whole-team" features, or whether that's a relevant concept, might be subjective — but that only means the importance of this question is subjective, like always.

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• Javascript Only Search Method [on hold]

  - by user2118228

  I need to put a search function on a website that is going to be on a CD-ROM with no access to the internet. It has 80 pages, and about 500 'items', so I'd prefer to not have to hard code 100's of 'if statements if possible. I've found a few programs you can buy that will index and generate results (Zoom Search, JSS Index, The German Guys') but there are odd quirks with each one. Plus I would rather code it myself to get complete control over it, and to really understand what it's doing. Basically searching for a few words would display the product image and description; clicking on that would take you the related URL. This is kind of complicated, I can't find an easy solution not dealing with hundreds of if Statements. Has anyone ever created anything like this or know a better method? I'm not really sure a better way to go about this. I've used PHP/MYSQL for search results before, but this cannot run any php.

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• Fixing a bug that has never caused a problem until now.

  - by codeelegance

  I recently made a change that caused some code to be run far more often than it used to. This lead to the discovery of a bug. This bug had the potential to happen any time that code was run but because it was run so seldom it never surfaced. When I brought this to the lead developer's attention he wanted me to undo the change that exposed the bug rather than fix the bug quoting the adage, "If it ain't broke, don't fix it". Its clear to me that we were just lucky up until now but he won't listen to reason. Should I fix it anyway? Update The lead technically doesn't have any authority over me. Just tenure. He's been the sole developer on the project for a number of years until a year ago and I think he doesn't take constructive criticism very well. For what's worth, I didn't criticize him I just pointed out that just because the bug never showed up didn't mean it wasn't there.

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• How to move a rectangle properly?

  - by bodycountPP

  I recently started to learn OpenGL. Right now I finished the first chapter of the "OpenGL SuperBible". There were two examples. The first had the complete code and showed how to draw a simple triangle. The second example is supposed to show how to move a rectangle using SpecialKeys. The only code provided for this example was the SpecialKeys method. I still tried to implement it but I had two problems. In the previous example I declared and instaciated vVerts in the SetupRC() method. Now as it is also used in the SpecialKeys() method, I moved the declaration and instantiation to the top of the code. Is this proper c++ practice? I copied the part where vertex positions are recalculated from the book, but I had to pick the vertices for the rectangle on my own. So now every time I press a key for the first time the rectangle's upper left vertex is moved to (-0,5:-0.5). This ok because of GLfloat blockX = vVerts[0]; //Upper left X GLfloat blockY = vVerts[7]; // Upper left Y But I also think that this is the reason why my rectangle is shifted in the beginning. After the first time a key was pressed everything works just fine. Here is my complete code I hope you can help me on those two points. GLBatch squareBatch; GLShaderManager shaderManager; //Load up a triangle GLfloat vVerts[] = {-0.5f,0.5f,0.0f, 0.5f,0.5f,0.0f, 0.5f,-0.5f,0.0f, -0.5f,-0.5f,0.0f}; //Window has changed size, or has just been created. //We need to use the window dimensions to set the viewport and the projection matrix. void ChangeSize(int w, int h) { glViewport(0,0,w,h); } //Called to draw the scene. void RenderScene(void) { //Clear the window with the current clearing color glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT|GL_STENCIL_BUFFER_BIT); GLfloat vRed[] = {1.0f,0.0f,0.0f,1.0f}; shaderManager.UseStockShader(GLT_SHADER_IDENTITY,vRed); squareBatch.Draw(); //perform the buffer swap to display the back buffer glutSwapBuffers(); } //This function does any needed initialization on the rendering context. //This is the first opportunity to do any OpenGL related Tasks. void SetupRC() { //Blue Background glClearColor(0.0f,0.0f,1.0f,1.0f); shaderManager.InitializeStockShaders(); squareBatch.Begin(GL_QUADS,4); squareBatch.CopyVertexData3f(vVerts); squareBatch.End(); } //Respond to arrow keys by moving the camera frame of reference void SpecialKeys(int key,int x,int y) { GLfloat stepSize = 0.025f; GLfloat blockSize = 0.5f; GLfloat blockX = vVerts[0]; //Upper left X GLfloat blockY = vVerts[7]; // Upper left Y if(key == GLUT_KEY_UP) { blockY += stepSize; } if(key == GLUT_KEY_DOWN){blockY -= stepSize;} if(key == GLUT_KEY_LEFT){blockX -= stepSize;} if(key == GLUT_KEY_RIGHT){blockX += stepSize;} //Recalculate vertex positions vVerts[0] = blockX; vVerts[1] = blockY - blockSize*2; vVerts[3] = blockX + blockSize * 2; vVerts[4] = blockY - blockSize *2; vVerts[6] = blockX+blockSize*2; vVerts[7] = blockY; vVerts[9] = blockX; vVerts[10] = blockY; squareBatch.CopyVertexData3f(vVerts); glutPostRedisplay(); } //Main entry point for GLUT based programs int main(int argc, char** argv) { //Sets the working directory. Not really needed gltSetWorkingDirectory(argv[0]); //Passes along the command-line parameters and initializes the GLUT library. glutInit(&argc,argv); //Tells the GLUT library what type of display mode to use, when creating the window. //Double buffered window, RGBA-Color mode,depth-buffer as part of our display, stencil buffer also available glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGBA|GLUT_DEPTH|GLUT_STENCIL); //Window size glutInitWindowSize(800,600); glutCreateWindow("MoveRect"); glutReshapeFunc(ChangeSize); glutDisplayFunc(RenderScene); glutSpecialFunc(SpecialKeys); //initialize GLEW library GLenum err = glewInit(); //Check that nothing goes wrong with the driver initialization before we try and do any rendering. if(GLEW_OK != err) { fprintf(stderr,"Glew Error: %s\n",glewGetErrorString); return 1; } SetupRC(); glutMainLoop(); return 0; }

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