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- 18:48, 10 July 2009 diff hist -10 m FAQ →How to render in pixel space
- 18:47, 10 July 2009 diff hist -10 m FAQ →Where can I download? #2
- 12:36, 5 July 2009 diff hist -2 m Common Mistakes →Palette
- 12:34, 5 July 2009 diff hist +1,573 Common Mistakes →Triple Buffering
- 19:12, 3 July 2009 diff hist +3,601 N Multisampling New page: Full Scene Anti-Aliasing - also called FSAA<br> The 1995 method of doing AA was to call glEnable(GL_POINT_SMOOTH), glEnable(GL_LINE_SMOOTH), glEnable(GL_POLYGON_SMOOTH) and to enable blend...
- 19:04, 3 July 2009 diff hist +18 General OpenGL
- 12:58, 21 June 2009 diff hist +946 FAQ →How Does It Work On Windows?
- 04:55, 18 June 2009 diff hist +3,908 Geometry Shader Examples
- 14:30, 17 June 2009 diff hist +4,412 N Geometry Shader Examples New page: GS = Geometry Shader<br> This is a short document about Geometry Shaders in OpenGL.<br> The first extension to be introduced was GL_EXT_geometry_shader4 on Oct 1, 2007.<br> Then it became ...
- 14:22, 17 June 2009 diff hist +97 Shading languages
- 21:49, 15 June 2009 diff hist +1,126 GLSL : common mistakes →glUniform causes a slow down
- 14:47, 13 June 2009 diff hist +365 History of OpenGL
- 14:58, 12 June 2009 diff hist +484 FAQ →Where can I download? #2
- 18:05, 11 June 2009 diff hist +1,803 FAQ →Which 3D API is better?
- 22:12, 8 June 2009 diff hist +1,631 N Fonts New page: OpenGL doesn't support font rendering since OpenGL is a basic 3D API.<br> Fonts require some OS interaction and font files to be installed, therefore core GL doesn't support fonts at all.<...
- 04:20, 8 June 2009 diff hist +1,335 Texture Combiners →Example : Blend tex0 and tex1 based on a blending factor you supply
- 22:20, 7 June 2009 diff hist +2,750 N Vertex Array Object New page: You might also want to read glVertexAttribPointer which is at http://www.opengl.org/wiki/GlVertexAttribPointer<br> <br> GL 3.0 introduces VAO (Vertex Array Object). It also introduces Gene...
- 21:52, 7 June 2009 diff hist +30 General OpenGL
- 13:26, 1 June 2009 diff hist +1,251 Getting Started
- 21:51, 30 May 2009 diff hist +2,382 N GluLookAt code New page: GLU - the OpenGL Utility library is an additional library that contains a handful of functions for additional tasks.<br> It is traditional and can be found in a lot of tutorials and exampl...
- 21:40, 30 May 2009 diff hist +21 m General OpenGL
- 14:55, 30 May 2009 diff hist +439 m Generic Vertex Attribute - examples
- 05:09, 30 May 2009 diff hist +209 m Generic Vertex Attribute - examples
- 04:46, 30 May 2009 diff hist +38 m Generic Vertex Attribute - examples
- 16:38, 29 May 2009 diff hist +2,620 N Generic Vertex Attribute - examples New page: With GL 2.0, a new way to specify your vertex information became available : glVertexAttribPointer<br> You could of course continue to use glVertexPointer, glTexCoordPointer, glNormalPoint...
- 16:10, 29 May 2009 diff hist +28 General OpenGL
- 23:22, 24 May 2009 diff hist +79 m Getting Started →OpenGL 3.0
- 14:15, 18 May 2009 diff hist +802 GLSL : common mistakes →glUniform causes a slow down
- 14:07, 18 May 2009 diff hist +60 m Texture Sampling
- 14:01, 17 May 2009 diff hist +156 Shadow Mapping without shaders
- 14:00, 17 May 2009 diff hist +3,330 N Shadow Mapping without shaders New page: Since there are websites that already discuss this well, and they are old, they don't use shaders, they don't use VBOs, they don't use FBOs, they use GL_ARB_depth_texture and GL_ARB_shadow...
- 13:37, 17 May 2009 diff hist -106 General OpenGL
- 13:50, 16 May 2009 diff hist +1 m GLSL : common mistakes →glUniform causes a slow down
- 13:50, 16 May 2009 diff hist +7 m GLSL : common mistakes →glUniform doesn't work
- 13:49, 16 May 2009 diff hist +1,197 GLSL : common mistakes →Compile GLSL
- 05:04, 16 May 2009 diff hist -10 m Common Mistakes
- 13:07, 15 May 2009 diff hist -1 m Texture Mapping →Windows and other OSes
- 13:04, 15 May 2009 diff hist +1,744 Texture Mapping →glBindTexture
- 00:20, 12 May 2009 diff hist +280 m Common Mistakes →Creating a Texture
- 15:31, 9 May 2009 diff hist +87 m Common Mistakes →Color Index, The imaging subset
- 15:29, 9 May 2009 diff hist +4 N Textures - compression New page: test current
- 15:28, 9 May 2009 diff hist +29 m General OpenGL
- 15:27, 9 May 2009 diff hist +756 Common Mistakes →Color Index, The imaging subset
- 05:31, 7 May 2009 diff hist +746 N GLSL : ATI/AMD specific features New page: When you compile your GLSL shader, if you exceed some hw limit, ATI/AMD let's you know by telling you the shader has exceeded "so and so" limit and therefore it will run in <b>software</b>... current
- 05:24, 7 May 2009 diff hist +144 m Shading languages
- 12:22, 5 May 2009 diff hist +14 m Multitexture with GLSL
- 03:56, 4 May 2009 diff hist +1,769 N Skybox New page: A lot of games, specially First Person Shooter (FPS) games need to render a skybox.<br> Typically, the skybox is just a cube. Some games render a sphere or a hemisphere but this doesn't gi...
- 03:42, 4 May 2009 diff hist +13 m General OpenGL
- 19:59, 3 May 2009 diff hist +3,796 N GluProject and gluUnProject code New page: GLU - the OpenGL Utility library is an additional library that contains a handful of functions for additional tasks.<br> It is traditional and can be found in a lot of tutorials and exampl...
- 05:30, 2 May 2009 diff hist +9 m Creating an OpenGL Context (WGL)
- 05:30, 2 May 2009 diff hist +1 m Creating an OpenGL Context (WGL)
- 05:29, 2 May 2009 diff hist -2 m Creating an OpenGL Context (WGL)
- 05:28, 2 May 2009 diff hist +146 Creating an OpenGL Context (WGL)
- 05:26, 2 May 2009 diff hist +1,193 N Creating an OpenGL Context (WGL) New page: In order to create a GL 3.x context (as of this writing, GL 3.1 spec is released), you need to do the following :<br> 1. Create a window.<br> 2. Setup the pixelformat just like you use to....
- 05:13, 2 May 2009 diff hist +48 m General OpenGL
- 14:57, 1 May 2009 diff hist +1,852 N GluPerspective code New page: GLU - the OpenGL Utility library is an additional library that contains a handful of functions for additional tasks.<br> It is traditional and can be found in a lot of tutorials and exampl...
- 14:45, 1 May 2009 diff hist +65 m General OpenGL
- 14:35, 1 May 2009 diff hist +236 m Common Mistakes →The Pixel Ownership Problem
- 14:33, 1 May 2009 diff hist +275 m Common Mistakes →Swap Buffers
- 14:30, 1 May 2009 diff hist +236 m Common Mistakes →Render To Texture
- 14:04, 22 April 2009 diff hist +381 FAQ
- 22:23, 6 April 2009 diff hist +981 N OpenGL and multithreading New page: === Can I create an OpenGL context for a control in a different thread than the one in which the was created on? === Yes. According to the Microsoft documents (MSDN), there is no restricti...
- 22:16, 6 April 2009 diff hist +32 m General OpenGL
- 13:37, 5 April 2009 diff hist +2,000 N Get Context Info New page: === glGetString(GL_VERSION) === This returns a string which may look something like "2.0.6914 WinXP SSE/SSE2/SSE3/3DNow!"<br> 2.0 is the actual version number of GL supported. All the rest...
- 13:27, 5 April 2009 diff hist +48 m General OpenGL
- 18:24, 25 March 2009 diff hist +1,096 m GLSL : common mistakes
- 14:01, 21 March 2009 diff hist +2,119 N Textures - more New page: One of the confusions that has always existed for newcomers is the way that texture format is handled by functions such as glTexImage2D and glTexImage3D.<br> There is the <b>internalFormat...
- 13:35, 21 March 2009 diff hist +22 m General OpenGL
- 03:05, 17 March 2009 diff hist +1,966 m Common Mistakes
- 13:26, 16 March 2009 diff hist +266 m FAQ →2 component textures
- 12:04, 13 March 2009 diff hist +308 m Floating point and mipmapping and filtering →GPUs and What is supported
- 14:00, 9 March 2009 diff hist +210 m Common Mistakes →glAreTexturesResident and Video Memory
- 17:54, 8 March 2009 diff hist +428 m FAQ →Multi indexed rendering
- 17:21, 7 March 2009 diff hist +285 m Texture Mapping →How to create a texture
- 14:24, 19 February 2009 diff hist +1,569 N P-buffer New page: Sometime in 2000, WGL_EXT_pbuffer was introduced and later on WGL_ARB_pbuffer and GLX_SGIX_pbuffer. This extension is for creating a pixel buffer (p-buffer), also called offscreen buffer. ...
- 14:07, 19 February 2009 diff hist +15 m General OpenGL
- 17:17, 17 February 2009 diff hist +130 m Texture Mapping →glBindTexture
- 14:54, 17 February 2009 diff hist +878 m Texture Mapping →glGenTextures
- 14:03, 17 February 2009 diff hist +1,400 m Texture Mapping
- 00:31, 16 February 2009 diff hist +4 m Getting Started →External Links
- 17:26, 12 February 2009 diff hist +134 m Debugging Tools
- 17:44, 10 February 2009 diff hist +92 m Vertex Specification Best Practices →Size of a VBO/IBO
- 17:42, 10 February 2009 diff hist +334 N Selection mechanism New page: Please read http://www.opengl.org/wiki/Common_Mistakes#Selection_and_Picking_and_Feedback_Mode<br> for alternative ways for selection and picking. This feature should never have been part ... current
- 18:16, 9 February 2009 diff hist +2,491 N Vertex Specification Best Practices New page: VBO = Vertex Buffer Object, a GL 1.5 feature<br> IBO = same as VBO, but it stands for Index Buffer Object. They are both essentially the same thing.<br> === Size of a VBO/IBO === How smal...
- 17:55, 9 February 2009 diff hist +17 m General OpenGL
- 18:37, 7 February 2009 diff hist +870 m FAQ →glTranslate, glRotate, glScale
- 17:40, 7 February 2009 diff hist +900 m FAQ →Which 3D API is better?
- 17:12, 5 February 2009 diff hist +1 m GL EXT framebuffer object More about FBOs →Color texture, Depth texture
- 17:10, 5 February 2009 diff hist +275 m GL EXT framebuffer object More about FBOs →Color texture, Depth texture
- 17:07, 5 February 2009 diff hist +3,771 m GL EXT framebuffer object More about FBOs
- 16:29, 31 January 2009 diff hist +842 m FAQ →Immediate mode, display lists, vertex arrays, VBO
- 19:37, 19 January 2009 diff hist +28 m Vertex Texture Fetch
- 19:35, 19 January 2009 diff hist +147 m Vertex Texture Fetch
- 15:54, 19 January 2009 diff hist +3,593 Selecting a Shading Language
- 21:19, 12 January 2009 diff hist +1,433 m FAQ
- 05:56, 10 January 2009 diff hist +484 m Skeletal Animation
- 06:27, 9 January 2009 diff hist +309 m Skeletal Animation
- 06:24, 9 January 2009 diff hist +65 m Skeletal Animation
- 18:35, 8 January 2009 diff hist +3,294 N Skeletal Animation
- 17:55, 8 January 2009 diff hist +131 m Shading languages
- 17:23, 3 January 2009 diff hist +1,830 N Fixed Function Texture Binding
- 17:05, 3 January 2009 diff hist +22 m General OpenGL
- 03:47, 2 January 2009 diff hist +2,434 m Framebuffer Object Extension Examples →Quick example, render_to_texture (Cubemap)
- 18:10, 27 December 2008 diff hist +92 m Client-Side Vertex Arrays
- 18:09, 27 December 2008 diff hist +1,207 Vertex Formats current
- 18:00, 27 December 2008 diff hist +2,106 N Vertex Formats
- 17:49, 27 December 2008 diff hist +21 m General OpenGL
- 17:49, 27 December 2008 diff hist +221 m Client-Side Vertex Arrays
- 17:43, 27 December 2008 diff hist +2,689 N Client-Side Vertex Arrays
- 17:29, 27 December 2008 diff hist +20 m General OpenGL
- 20:33, 21 December 2008 diff hist +2,083 N GL EXT framebuffer object More about FBOs
- 20:13, 21 December 2008 diff hist +48 m OpenGL Extension →Framebuffer related extensions
- 17:43, 19 December 2008 diff hist +11 m GL EXT framebuffer multisample current
- 15:52, 19 December 2008 diff hist +2,998 N Texturing a Sphere
- 15:29, 19 December 2008 diff hist +25 m General OpenGL
- 19:39, 15 December 2008 diff hist +755 m Hardware specifics: ATI
- 19:31, 15 December 2008 diff hist -9 m NPOT Texture →OpenGL 2.0 and GL_ARB_texture_non_power_of_two
- 19:30, 15 December 2008 diff hist -14 m Common Mistakes →Updating A Texture
- 19:29, 15 December 2008 diff hist +29 m Common Mistakes →Creating a Cubemap Texture
- 18:22, 12 December 2008 diff hist +118 m NPOT Texture
- 18:21, 12 December 2008 diff hist -292 m GL EXT framebuffer multisample
- 18:20, 12 December 2008 diff hist -867 m Framebuffer Object Extension Examples
- 19:01, 10 December 2008 diff hist +1,446 N GLSL : nVidia specific features
- 18:47, 10 December 2008 diff hist +142 m Shading languages
- 03:23, 9 December 2008 diff hist +59 m Texture Sampling
- 03:19, 9 December 2008 diff hist -28 m GL EXT texture integer →Create The Texture
- 02:14, 6 December 2008 diff hist +1,048 m FAQ
- 17:28, 5 December 2008 diff hist +1 m Platform specifics: Windows →SwapInterval aka vsyc
- 17:28, 5 December 2008 diff hist +180 m Platform specifics: Windows →wglShareLists
- 17:26, 5 December 2008 diff hist +1,956 N Swap Interval
- 17:07, 5 December 2008 diff hist +28 m Platform specifics: Linux
- 14:53, 1 December 2008 diff hist +1,005 m Debugging Tools
- 14:36, 1 December 2008 diff hist +2,790 m FAQ
- 19:57, 29 November 2008 diff hist +1,628 m Texture Sampling
- 19:40, 29 November 2008 diff hist +1,580 N Texture Sampling
- 19:10, 29 November 2008 diff hist +141 m Shading languages
- 16:29, 29 November 2008 diff hist +1,247 m Texture Mapping
- 19:32, 26 November 2008 diff hist +631 m Vertex Texture Fetch
- 06:44, 16 November 2008 diff hist +302 m Getting Started →External Links
- 06:43, 16 November 2008 diff hist +767 m Getting Started →External Links
- 18:10, 15 November 2008 diff hist +114 m Getting Started →External Links
- 05:51, 11 November 2008 diff hist -104 m Common Mistakes
- 05:48, 11 November 2008 diff hist +679 m Common Mistakes →Creating a Texture
- 05:45, 11 November 2008 diff hist -24 m NPOT Texture →OpenGL 2.0 and GL_ARB_texture_non_power_of_two
- 05:43, 11 November 2008 diff hist +292 m Texture Mapping
- 05:29, 11 November 2008 diff hist +190 m Vertex Texture Fetch
- 17:26, 8 November 2008 diff hist +362 m Common Mistakes →Color Index, The imaging subset
- 19:21, 2 November 2008 diff hist +872 m Getting Started →OpenGL 2.0+ and extensions
- 19:08, 2 November 2008 diff hist +340 m Framebuffer Object Extension Examples
- 19:05, 2 November 2008 diff hist +230 m Framebuffer Object Extension Examples
- 05:48, 2 November 2008 diff hist +175 m GL EXT framebuffer multisample →Examples :
- 05:44, 2 November 2008 diff hist +686 m Framebuffer Object Extension Examples
- 17:07, 30 October 2008 diff hist +1,137 m Platform specifics: Windows →What about the WGL functions?
- 03:43, 26 October 2008 diff hist +2,763 N Mathematics of glTexGen
- 03:14, 26 October 2008 diff hist +30 m General OpenGL
- 18:03, 23 October 2008 diff hist +3,823 N Texture Combiners
- 16:46, 23 October 2008 diff hist +24 m General OpenGL
- 03:55, 20 October 2008 diff hist +1,988 N GL EXT texture integer
- 03:37, 20 October 2008 diff hist +59 m OpenGL Extension →Texturing related extensions
- 18:19, 19 October 2008 diff hist +3,881 Floating point and mipmapping and filtering
- 18:00, 19 October 2008 diff hist -21 m OpenGL Extension →Texturing related extensions
- 18:00, 19 October 2008 diff hist +21 m OpenGL Extension →Texturing related extensions
- 05:07, 11 October 2008 diff hist +575 m Common Mistakes
- 15:01, 10 October 2008 diff hist +1,050 m FAQ
- 15:00, 9 October 2008 diff hist +390 m Getting Started →OpenGL 2.0 and extensions
- 01:49, 8 October 2008 diff hist +1,283 m GL EXT framebuffer multisample
- 16:03, 7 October 2008 diff hist +414 m GL EXT framebuffer multisample
- 16:00, 7 October 2008 diff hist +1,207 m Framebuffer Object Extension Examples
- 15:55, 7 October 2008 diff hist +94 m Vertex Buffer Object →Sample Code
- 15:47, 7 October 2008 diff hist +61 m Common Mistakes →Creating a Cubemap Texture
- 15:46, 7 October 2008 diff hist +60 m Common Mistakes →Creating a Texture
- 16:52, 2 October 2008 diff hist +883 N OpenGL Error Codes
- 16:44, 2 October 2008 diff hist +21 m General OpenGL
- 16:32, 2 October 2008 diff hist +3,916 N GL EXT framebuffer multisample
- 16:19, 2 October 2008 diff hist +37 m OpenGL Extension →Framebuffer related extensions
- 15:08, 1 October 2008 diff hist +1,507 m Common Mistakes
- 15:16, 29 September 2008 diff hist +2,248 m Common Mistakes
- 21:40, 28 September 2008 diff hist +1,538 Platform specifics: Windows
- 01:20, 27 September 2008 diff hist +473 m Common Mistakes →Texture Precision
- 05:49, 25 September 2008 diff hist +1,206 m Common Mistakes →Creating a Texture
- 01:10, 21 September 2008 diff hist +247 m GLSL : common mistakes →Easy Optimization
- 01:10, 21 September 2008 diff hist +250 m GLSL : common mistakes →Not Used
- 01:07, 21 September 2008 diff hist +80 m OpenGL Shading Language →A sample trivial GLSL Fragment Shader
- 01:07, 21 September 2008 diff hist +86 m OpenGL Shading Language →A sample trivial GLSL Vertex Shader
- 16:56, 20 September 2008 diff hist +8 m Getting Started →OpenGL Viewers
- 14:08, 19 September 2008 diff hist +174 m Vertex Texture Fetch
- 22:27, 18 September 2008 diff hist +803 FAQ
- 22:20, 18 September 2008 diff hist +1,803 N FAQ
- 22:03, 18 September 2008 diff hist +39 General OpenGL
- 14:20, 16 September 2008 diff hist +1,461 Common Mistakes
- 04:17, 11 September 2008 diff hist +451 Common Mistakes →Unsupported formats #3
- 04:59, 10 September 2008 diff hist +201 m Vertex Buffer Object →Sample Code
- 17:35, 8 September 2008 diff hist +225 GLSL : common mistakes
- 04:55, 31 August 2008 diff hist +3,411 Framebuffer Object Extension Examples
- 16:48, 27 August 2008 diff hist +384 m Vertex Texture Fetch
- 05:45, 26 August 2008 diff hist +2,509 m Framebuffer Object Extension Examples
- 04:30, 26 August 2008 diff hist +21 m Common Mistakes →Creating a Cubemap Texture
- 04:29, 26 August 2008 diff hist +1,589 m Common Mistakes →Creating a Texture
- 23:08, 23 August 2008 diff hist +335 m OpenGL Shading Language →A sample trivial GLSL Vertex Shader
- 13:17, 23 August 2008 diff hist +44 m Vertex Buffer Object
- 13:16, 23 August 2008 diff hist +9,035 N Vertex Buffer Object
- 13:13, 23 August 2008 diff hist +10 m General OpenGL
- 17:31, 21 August 2008 diff hist +34 m Common Mistakes →Render To Texture
- 17:25, 21 August 2008 diff hist +245 m GLSL : common mistakes
- 01:28, 17 August 2008 diff hist +660 m GLSL : common mistakes
- 01:17, 17 August 2008 diff hist +371 m GLSL : common mistakes
- 16:22, 12 August 2008 diff hist +100 m FAQ/Depth Buffer
- 19:39, 2 August 2008 diff hist -3 m Common Mistakes →Texture Border Color Problem
- 19:38, 2 August 2008 diff hist +566 m Common Mistakes
- 18:15, 30 July 2008 diff hist +1,213 N Debugging Tools
- 18:03, 30 July 2008 diff hist +22 m General OpenGL
- 18:02, 30 July 2008 diff hist +74 m Getting Started →OpenGL Viewers
- 02:14, 28 July 2008 diff hist +850 Common Mistakes
- 05:23, 26 July 2008 diff hist +2,372 N Vertex Transformation
- 04:35, 26 July 2008 diff hist +28 General OpenGL
- 17:13, 22 July 2008 diff hist +3,128 Common Mistakes →Creating a Texture
- 18:09, 20 July 2008 diff hist +230 m Common Mistakes →Creating a Texture
- 02:29, 20 July 2008 diff hist +1,349 Common Mistakes
- 14:23, 14 July 2008 diff hist +1,389 Common Mistakes
- 20:36, 12 July 2008 diff hist +74 m Common Mistakes →Render To Texture
- 20:34, 12 July 2008 diff hist +509 Common Mistakes →Creating a Texture
- 13:39, 11 July 2008 diff hist +103 m Detecting the Shader Model
- 15:04, 8 July 2008 diff hist +547 m Common Mistakes →Creating a Texture
- 15:03, 8 July 2008 diff hist +1 m Common Mistakes →When Your Texture
- 15:00, 8 July 2008 diff hist +1,674 Common Mistakes
- 23:55, 5 July 2008 diff hist +1,870 N Multitexture with GLSL
- 23:47, 5 July 2008 diff hist +29 General OpenGL
- 17:41, 4 July 2008 diff hist +2,252 N Framebuffer Object Extension Examples
- 15:36, 4 July 2008 diff hist +4 m Common Mistakes →glEnableClientState(GL_INDEX_ARRAY)
- 15:35, 4 July 2008 diff hist +2,247 Common Mistakes
- 17:39, 2 July 2008 diff hist +1,474 N Common Mistakes
- 17:25, 2 July 2008 diff hist +22 General OpenGL
- 02:56, 29 June 2008 diff hist +75 m Getting Started →External Links
- 14:37, 21 June 2008 diff hist +327 m Getting Started →External Links
- 15:17, 27 May 2008 diff hist +345 m GLSL : common mistakes →Binding A Texture
- 15:15, 27 May 2008 diff hist +429 m GLSL : common mistakes →Binding A Texture
- 00:20, 25 May 2008 diff hist +2,317 m Texture Mapping
- 23:47, 24 May 2008 diff hist -1 m General OpenGL
- 23:47, 24 May 2008 diff hist +8 General OpenGL
- 23:47, 24 May 2008 diff hist -7 m General OpenGL
- 15:37, 22 May 2008 diff hist +3,575 N NPOT Texture
- 15:07, 22 May 2008 diff hist +20 m General OpenGL
- 20:51, 20 May 2008 diff hist +3,052 N Vertex Texture Fetch
- 20:19, 20 May 2008 diff hist +144 m Shading languages
- 20:22, 5 May 2008 diff hist +447 m Getting Started
- 19:59, 5 May 2008 diff hist +168 m Getting Started →Windows
- 16:40, 17 April 2008 diff hist +21 m OpenGL Extension →Extensions of Interest for the GL 2 Programmer
- 16:21, 17 April 2008 diff hist -2 m OpenGL Extension
- 16:19, 17 April 2008 diff hist +1,662 OpenGL Extension
- 15:26, 8 April 2008 diff hist +35 m GLSL : common mistakes →The MAD instruction