statistics.glsl

 
#version 330
 
#ifdef VERTEX_SHADER
layout(location= 0) in vec3 position;
 
uniform mat4 mvpMatrix;
uniform mat4 mvMatrix;
 
out vec3 vertex_position;
void main( )
{
    gl_Position= mvpMatrix * vec4(position, 1);
    vertex_position= vec3(mvMatrix * vec4(position, 1));
}
#endif
 
#ifdef FRAGMENT_SHADER
in vec3 vertex_position;
 
#ifdef EARLY_TESTS
layout(early_fragment_tests) in;
#endif
 
out vec4 fragment_color;
void main( )
{
    // recalcule la normale 
    // permet de recharger les objets passes a travers M2/vertices / optimisation 
    vec3 t= dFdx(vertex_position);
    vec3 b= dFdy(vertex_position);
    vec3 n= normalize( cross(t, b) );
    
    float cos_theta= abs(n.z);
    vec3 color= vec3(1) * cos_theta;
    fragment_color= vec4(color, 1);
}
#endif