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levjs

OpenGL GLSL gl_LightSource[] Won't Accept Parameters Bigger Than 0

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Hi, I have been messing around with GLSL for the first time recently, I am not new to OpenGL, and I have implemented Per-Pixel-Lighting and such for one light. Now I want to implement it for more than one light. The only problem is that gl_LightSource[x].variable with x greater than 0 crashes the program...but this is weird...only when I shut down the window, specifically, when I try to delete the window context. What is going on here. Am I somehow corrupting the windows memory? Thanks for any help you can give. Thanks, Levi [Edited by - levjs on August 14, 2007 4:58:02 PM]

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No, I don't believe you need to enable the lights when you are shading.

Actually, the program breaks when I try to delete the program(I have detached the shaders and all that). If I don't try to delete the program, then it breaks when I try to destroy the window context.

I have no idea what's going on. I may have to just use uniform variables to transfer the lighting information if I can't figure this out.

Levi

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You don't need to enable lights. Same for textures : glEnable(GL_TEXTURE_2D is ignored.

Do you have gl_LightSource[x].variable in yuor code or gl_LightSource[1].variable. It's possible the previous is not supported on your card.
Also, I recommend that you don't use gl_LightSource[x] or any other built in variables. Just upload those things as uniform.
I say this because some drivers have bugs.

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I use the gl_LightSource[1] in my code. Also, I am trying to use uniform variables; I've created a struct for the lighting variables. The thing is, I'm not sure how to pass structures as uniforms. Do I just pass the individual variables, and then declare the struct in my shader as well??

Thanks for all your help.
Levi

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Quote:
Original post by levjs
Do I just pass the individual variables, and then declare the struct in my shader as well??


Yes.

struct thing
{
float value;
vec4 value2;
};

thing zing; //this is an instance of thing

You need to get location of zing.value and zing.value2 and update values using glUniform1f and glUniform4f

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