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<html lang="en" >
<head>
<meta charset="UTF-8">
<title>#85 in 2021 / GLSL Shader</title>
<link rel="stylesheet" href="css/normalize.min.css">
</head>
<body>
<script id="fs" type="x-shader/x-fragment">
precision mediump float;
uniform float time;
uniform vec2 mouse;
uniform vec2 resolution;
// window ratio
float ratio = resolution.x / resolution.y;
float PI = 3.1415926;
float a = PI * 2.0 / 72.0;
mat2 scale(vec2 scale){
return mat2(scale.x, 0.0, 0.0, scale.y);
}
void main(void) {
// center center
vec2 p = vec2(gl_FragCoord.xy * 2.0 - resolution) / min(resolution.x, resolution.y);
// left bottom
//vec2 p = gl_FragCoord.xy / resolution.xy;
float l = length(p);
vec3 c = vec3(l, abs(sin(time) * 1.0 - p.x), abs(cos(time) * 1.0 - p.y));
float d = 0.0;
for (float i = 0.0; i < 72.0; i++) {
p = p + vec2(cos(time) / 100.0, sin(time) / 100.0);
vec2 q = p + vec2(
cos((0.0 - time * 2.0) * PI / 180.0 * i),
sin((0.0 - time * 2.0) * PI / 180.0 * i)) * (0.03 * i);
d += 0.01 / length(q);
}
d = pow(d, 2.0);
gl_FragColor = vec4(c * d, 1.0);
}
</script>
<script id="vs" type="x-shader/x-vertex">
attribute vec3 position;
void main(void){
gl_Position = vec4(position, 1.0);
}
</script>
<script src="js/script.js"></script>
</body>
</html>
