Materials Example

#version 330

layout(location = 0) in vec3 in_position;
layout(location = 1) in vec3 in_normal;
layout(location = 2) in vec3 in_colour;

out vec3 pass_colour;

uniform mat4 mvpMatrix;

uniform vec3 material1;
uniform vec3 material2;


vec3 decodeColourCode(float code){
    vec3 weights = vec3(0.0);
    weights.x = mod(code, 2.0);
    code = (code - weights.x) * 0.5;
    weights.y = mod(code, 2.0);
    weights.z = (code - weights.y) * 0.5;
    return weights;
}

vec3 customizeColour(vec2 colourData, vec3 materialColour){
    vec3 weights = decodeColourCode(colourData.x);
    vec3 result = materialColour + (weights * colourData.y);
    return clamp(result, 0.0, 1.0);
}

void main(void){

    gl_Position = mvpMatrix * vec4(in_position, 1.0);

    pass_colour = in_colour;
    if(colour.x < -1.5){
        colour = customizeColour(colour.yz, material2);
    }else if(colour.x < -0.5){
        colour = customizeColour(colour.yz, material1);
    }

}