gistfile1.txt

void main (void)
{
	float depth = texture2D(tex_depth, gl_TexCoord[0].st).r * 2.0 - 1.0;
	vec3 norm = texture2D(tex_norm, gl_TexCoord[0].st).xyz * 2.0 - 1.0;
	//norm = normalize(norm); // no need?
	vec4 ambient = texture2D(tex_motion, gl_TexCoord[0].st); // currently holds ambient colors
	                                                         // will be used for velocity in future
	
	// Viewport position at this pixel in the range -1 to 1.
	vec4 projection_pos = vec4(gl_TexCoord[0].st * 2.0 - 1.0, depth, 1.0);
		
	// Transform by the view-projection inverse.
	vec4 viewport_pos = invprojmtx * projection_pos;
		
	// Divide by w to get the world position.
	vec4 frag_pos = viewport_pos / viewport_pos.w;

// ... blinn-phong calculations

	gl_FragColor = final_color;
}