Hi guys, I'm hoping smeone can give me some advice.
I recently got "Beginning OpenGL Game Programming 2nd edition" by Luke Bernstead.

The first thing i have been doing is doing is reading through and compiling / running the projects.
When I get to the first one with a fragment shader (Chapter 6) however, it bombs out. After some debugging, I've narrowed it down to the fragment shader.

this is the supplied shader:

#version 130

in vec4 color;
out vec4 outColor;

void main(void) {
outColor = color;
}

I tried changing the shader to something like this, which allows the program to run but everything is rendered black:
void main()
{
gl_FragColor = gl_Color;
}
[as far as I can tell this is deprecated anyway]


I also mentioned the vert shader works; here it is:
#version 130

uniform mat4 projection_matrix;
uniform mat4 modelview_matrix;

in vec3 a_Vertex;
in vec3 a_Color;
out vec4 color;

void main(void)
{
vec4 pos = modelview_matrix * vec4(a_Vertex, 1.0);
gl_Position = projection_matrix * pos;
color = vec4(a_Color, 1.0);
}


When I investigate what glGetShaderInfoLog says, all i get is:

- Fragment Shader Fai

useful, huh?


Unfortunately, I'm new to this whole thing and after a lot of searching on-line I'm still at an impasse. I hoping by posting here someone would be able to help me.

Oh yeah, my laptop's graphics card is: ATI Radeon HD 4500 series. I ran GPUCapsViewer; which told me that the card is fully shader version 1.3 compatible.

Any help appreciated, am i doing something wrong?!
[/quote]
If you are going to change the fragment shader, it needs to be compatible with the vertex shader. You have a varying variable called color from the vertex shader being passed to the fragment shader but where is it declared? You need to do this if you want to use the built-in type:
#version 130

in vec4 color;

void main(void) {
gl_FragColor = color;
}
Personally, when I am learning from a book with source code, I don't build the projects until I understand the underlying code. That way whether it compiles or not, I will be in a position to get it to work. The alternative is too frustrating.