I am using OpenGL 3.3 and am tryin to implement shadow mapping using cube maps. I have a framebuffer with a depth attachment and a cube map texture.

My question is how to design the shaders for the first pass, when creating the shadowmap.

This is my vertex shader:

in vec3 position;

uniform mat4 lightWVP;

void main()
{
    gl_Position = lightWVP * vec4(position, 1.0);
}

Now, do I even need a fragment shader in this shader pass? from what I understand after reading http://www.opengl.org/wiki/Fragment_Shader, by default gl_FragCoord.z is written to the currently attached depth component (to which my cubemap texture is bound to).

Thus I shouldnt even need a fragment shader for this pass and from what I understand, there is no other work to do in the fragment shader other than writing this value.

Is this correct?