path: root/src/shader.frag

#version 450

layout(location = 0) in vec3 fragColor;
layout(location = 1) in vec2 fragPos;

layout(location = 0) out vec4 outColor;

layout(binding = 0) uniform UniformBufferObject {
  mat4 model;
  mat4 view;
  mat4 proj;
  vec2 resolution;
} ubo;

// vec4 ubo_proj(vec2 v) {
//   return ubo.proj * ubo.view * ubo.model * vec4(v, 0.0, 1.0);
// }

// void main() {
//   // float x = gl_FragCoord.x / ubo.resolution.x;
//   // float y = gl_FragCoord.y / ubo.resolution.y;
//   float x = ubo_proj(vec2(gl_FragCoord.x, gl_FragCoord.y)).x / ubo.resolution.x;
//   float y = ubo_proj(vec2(gl_FragCoord.x, gl_FragCoord.y)).y / ubo.resolution.y;
//   //bool colored = mod(gl_FragCoord.x, 10) > 9 || mod(gl_FragCoord.y, 10) > 9;
//   bool colored = mod(x,0.1) > 0.09 || mod(y, 0.1) > 0.09;
//   if (colored) {
//     outColor = vec4(gl_FragCoord.x / ubo.resolution.x, gl_FragCoord.y / ubo.resolution.y, 1.0, 1.0);
//   } else {
//     outColor = vec4(0,0,0, 1.0);
//   }
//   //outColor = vec4(fragColor, 1.0);
// }
vec3 mandel(vec2 z0) {
    float k = 0.0;
    vec2 z = vec2(0.0);
    for(int i = 0; i < 420; ++i) {
        z = vec2(z.x*z.x-z.y*z.y, z.x*z.y*2.0) + z0;
        if (length(z) > 20.0) break;
        k += 1.0;
    }
    float mu = k + 1.0 - log2(log(length(z)));
    return sin(mu*0.1 + vec3(0.0,0.5,1.0));
}
void main() {
    float ar = ubo.resolution.x / ubo.resolution.y;
    vec2 uv = gl_FragCoord.xy / ubo.resolution.yy - vec2(0.66 * ar, 0.5);
    // uv = uv * 2.0 + vec2(-0.3, 0.0);
    float p = 30.0;
    float t = mod(13.0, p);
    if (t > p/2.0) t = p - t;
    float scale = 0.5 + pow(2.0, t);
    vec2 offset = vec2(-1.36799, .01);
    uv += offset*scale;
    uv /= scale;
    outColor = vec4(mandel(uv), 1.0);
}