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pixelhead

OpenGL [GLSL] get version in c code?

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Hi - I'm trying to make a program compatible with older OpenGL versions and am running into problems with GLSL. I need to detect if the GLSL code will run since if it doesn't I have to turn on some features in software. My basic question is, how does one query the GLSL version from C code? I have tried adding the #version 110 macro into my shader and it causes a compile error (unknown directive). The test machine has OpenGL 1.5.1 and probably GLSL < 1.1 (#version was added in GLSL 1.1 right?). Without the #version, it compiles fine but the rendering is not quite right. I didn't think I was doing anything too complicated: <code> vec3 normal, lightDir, viewVector, halfVector; vec4 diffuse, ambient, globalAmbient, specular = vec4(0.0); float NdotL,NdotHV; normal = normalize(gl_NormalMatrix * gl_Normal); lightDir = normalize(vec3(gl_LightSource[0].position)); NdotL = max(dot(normal, lightDir), 0.0); // set color gl_FrontColor = NdotL * gl_Color; </code> Thanks.

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how does one query the GLSL version from C code?

glGetString( GL_VERSION )
glGetString( GL_SHADING_LANGUAGE_VERSION_ARB )

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Thanks zedz for the info! Thought it might be something simple.

I dug around a bit more and you can query the GL_ARB_shading_language_100 extension for GLSL support and the glGetString() method for version.

For more details:

http://www.opengl.org/sdk/docs/tutorials/ClockworkCoders/extensions_part2.php

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