attribute vec3 aVertexPosition;
attribute vec4 aVertexColor;

uniform mat4 uMVMatrix;
uniform mat4 uPMatrix;

varying vec4 vColor;

uniform float f; // this is incremented every frame
uniform float t; // this is time in milliseconds since epoch

#define M_PI 3.1415926535897932384626433832795


mat3 rotateX(float rad) {
    float c = cos(rad);
    float s = sin(rad);
    return mat3(
        1.0, 0.0, 0.0,
        0.0, c, s,
        0.0, -s, c
    );
}


mat3 rotateY(float rad) {
    float c = cos(rad);
    float s = sin(rad);
    return mat3(
        c, 0.0, -s,
        0.0, 1.0, 0.0,
        s, 0.0, c
    );
}


mat3 rotateZ(float rad) {
    float c = cos(rad);
    float s = sin(rad);
    return mat3(
        c, s, 0.0,
        -s, c, 0.0,
        0.0, 0.0, 1.0
    );
}



void main(void) {
    gl_Position = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1);
    vec3 oColor = vec3(1.0,1.0,1.0);

    float min = 0.0;
    vec3 vertexPosition = aVertexPosition.xyz * rotateX(sin(f/30.0)) * rotateY(cos(f/25.0)) * rotateZ(tan(f/100.0)) / 5.0;

    if(vertexPosition.x > min && vertexPosition.y > min && vertexPosition.z > min) {
       oColor = vec3(1.0,0.0,0.0);
    }

    vColor = vec4(oColor,1.0);
}