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p0is0n

OpenGL GLSL beginner questions/advice

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p0is0n    100
Hi all. I'm starting to look into GLSL for writing shaders. Only used HLSL before. I am using the tutorials mentioned in the forum faq (clockwork coders, and lighthouse) also using gametutorials. From just searching on the internet when I got stuck I found people saying not to use the ARB extensions/function pointers anymore as openGL version 2.0 uses different ones. Also found people saying not to use gl_FragColor etc.. in shaders anymore. As I am just starting shaders I would rather start it the right way instead of going about it in an old and depreciated way. Note that I do have a simple shader that just sets the vertex transform and texture working using the ARB extensions/function pointers. I am not using GLEW because I don't want to have to include dll's with my project. I am also using windows and c++ by the way. Am I meant to use the ARB extensions? where can I find information on the alternative? Should I just get the orange book? would that answer all my questions? Any advice/clarifications on what the standard is to use would be appreciated. I mainly use DirectX so I am not used to all of these function pointers that need to be used to extend functionallity past version 1.00. [Edited by - p0is0n on May 4, 2009 6:16:58 PM]

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zedz    291
>>Am I meant to use the ARB extensions?
Always If possible (if for the cleanness/less typing if nothing else)

often when a function becomes part of the core opengl the only changes are nameing
eg glFuncARB(..) becomes glFunc(..)
but with glsl IIRC some things changed when glsl became part of the opengl core

http://www.opengl.org/wiki/OpenGL_extensions

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