uniform float mode = 0;
uniform float width = 0.2;
uniform float speed = 4.0;

#define PI 3.1415926535897932384626433832795


float t(float minv, float maxv, float m) {
    float range = (maxv - minv);
    return (minv + range/2) + (range/2) * sin(iGlobalTime * m);
}
float pulse(float freq) {
    return 0.5 + 0.25 * sin(iGlobalTime * freq);
}

float getProceduralColors(inout vec3 diffuse, inout vec3 specular, inout float shininess) {
    if (abs(_modelNormal.y) > width) {
        discard;
    }
    if (mode == 0) {
        diffuse = vec3(t(.5, 1, 5), t(.5, 1, 3), t(.5, 1, 2));
        if (abs(_modelNormal.y) > width) {
            discard;
        }
        return 1.0;
    } else if (mode == 1) {
        float count = 2;
        float rad = mod(iGlobalTime * 2.0, 2 * PI);
        rad -= PI;
        rad += _modelNormal.y / 0.25;
        float currad = atan(_modelNormal.z, _modelNormal.x);
        currad = mod((currad + PI) * count, 2 * PI);
        currad -= PI;
        diffuse = vec3(t(.5, 1, 5), t(.5, 1, 3), t(.5, 1, 2));
        float drad = abs(currad - rad);
        if (drad > PI) {
            drad = 2 * PI - drad;
        }
        if (drad > PI/2) {
            discard;
        }
        return 1.0;
    } else if (mode == 2) {
        float color = floor(mod(iGlobalTime * 5, 6.0));
        if (color == 0) {
            diffuse = vec3(1, .3, .7);
        } else if (color == 2) {
            diffuse = vec3(66/255.0, 232/255.0, 244/255.0);
        } else if (color == 4) {
            diffuse = vec3(179/255.0, 66/255.0, 244/255.0);
        } else {
            discard;
        }
        return 1.0;
    } else if (mode == 3) {
        float count = 4 + 50 * sin(iGlobalTime * 1);
        float rad = mod(iGlobalTime * 2.0, 2 * PI);
        rad -= PI;
        rad += _modelNormal.y / 0.25;
        float currad = atan(_modelNormal.z, _modelNormal.x);
        currad = mod((currad + PI) * count, 2 * PI);
        currad -= PI;
        diffuse = vec3(t(.5, 1, 5), t(.5, 1, 3), t(.5, 1, 2));
        float drad = abs(currad - rad);
        if (drad > PI) {
            drad = 2 * PI - drad;
        }
        if (drad > PI/2) {
            discard;
        }
        return 1.0;
    } else if (mode == 4) {
        float count = 20;
        float rad = mod(iGlobalTime * 2.0, 2 * PI);
        rad -= PI;
        rad += _modelNormal.y / 0.5;
        float currad = atan(_modelNormal.z, _modelNormal.x);
        currad = mod((currad + PI) * count, 2 * PI);
        currad -= PI;
        diffuse = vec3(t(.5, 1, 5), t(.5, 1, 3), t(.5, 1, 2));
        float drad = abs(currad - rad);
        if (drad > PI) {
            drad = 2 * PI - drad;
        }
        if (drad > 0.3) {
            discard;
        }
        return 1.0;
    }
    //float size = 0.5 + (1 + sin(iGlobalTime * 2)) * 0.14;
    diffuse = vec3(1.0, 0, 0);
    return 1.0;
}