Question

What do the default vertex, fragment and geometry GLSL shaders look like for version #330?

I’ll be using #version 330 GLSL Version 3.30 NVIDIA via Cg compiler, because that is what my graphics card supports.

With default shaders, I mean shaders that do the same exact thing as the graphics card would do when the shader program is turned off.

I can’t find a good example for #version 330. Been googling all day. Not sure if the term default shader is called something else like trivial or basic and if that is why I can’t find it.

Any recommendations for a book with version 330 or link to an easy beginner tutorial with version 330 would be great as well.

example of a trivial vertex shader in #version 110, does the default vertex transformation

#version 110

void main()
{
    gl_Position = gl_ProjectionMatrix * gl_ModelViewMatrix * gl_Vertex;
}

example of a trivial fragment shader in #version 110, turns color into red

#version 110

void main()
{
    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
}

Answer 1

There are no “default” shaders with OpenGL. It looks like what you want a very simple example of a shader that transforms vertices to clip space and gives them a color, so here you go:

Vertex shader:

#version 330

layout(location = 0)in vec4 vert;

uniform mat4 projection;
uniform mat4 view;
uniform mat4 model;

void main()
{
    gl_Position = projection * view * model * vert;
}

Fragment shader:

#version 330

out vec4 fragColor;

void main()
{
    fragColor = vec4(1.0, 0.0, 0.0, 1.0);
}

The core OpenGL 3.3 profile drops support for a lot of old fixed-function things like the matrix stack. You are expected to handle your own matrices and send them to your shaders. There is no ftransform, and gl_Position is pretty much the only valid gl_* variable.

While glBindAttribLocation is not deprecated, the preferred method of defining the location of vertex attributes is through “layout(location = x)” in GLSL.

In the vertex shader, “attribute” is now “in” and “varying” is now “out”. In the fragment shader, “varying” is now “in” and “gl_FragColor” is defined by an “out” variable. I believe that gl_FragColor is still valid, but now it’s possible to use an out variable to define the color.

This tutorial is very good and teaches core OpenGL and GLSL 3.30, I would recommend you use it to help you learn more about GLSL. Also remember that the GLSL Reference Pages is your friend.