Add suns.glsl

suns.glsl

@@ -0,0 +1,70 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+uniform vec2  resolution;
+uniform float time;
+
+struct Ray {
+	vec3 o;
+	vec3 d;
+};
+
+// dueling mandelbulbs
+// @acaudwell
+
+// http://www.fractalforums.com/mandelbulb-implementation/realtime-renderingoptimisations/
+
+float mandelbulb(in vec3 p, float power) {
+
+	float dr = 1.0;
+	float r  = length(p);
+
+	vec3 c = p;
+
+	for(int i=0; i<2; i++) {
+
+		float zo0 = asin(p.z / r);
+		float zi0 = atan(p.y, p.x);
+		float zr  = pow(r, power-1.0);
+		float zo  = (zo0) * power;
+		float zi  = (zi0) * power;
+		float czo=cos(zo);
+
+		dr = zr * dr * power + 1.0;
+		zr *= r;
+
+		p = zr * vec3(czo*cos(zi), czo*sin(zi), sin(zo));
+
+		p += c;
+
+		r = length(p);
+	}
+
+	return 0.5 * r * log(r) / r;
+}
+
+void main() {
+	vec2 p = ((gl_FragCoord.xy / resolution.xy) * 2.0 - 1.0) * 2.5;
+
+	float t = time;
+
+	Ray ray1;
+	ray1.o = vec3(0.0);
+	ray1.d = normalize( vec3((p - 1.5*vec2(sin(t-2.0), cos(t+1.0))) * vec2(resolution.x/resolution.y, 1.0), 1.0 ) );
+
+	Ray ray2;
+	ray2.o = vec3(0.0);
+	ray2.d = normalize( vec3((p - 1.5*vec2(cos(-t),sin(t))) * vec2(resolution.x/resolution.y, 1.0), 1.0 ) );
+
+	ray1.d.xy = vec2( ray1.d.x * cos(t) - ray1.d.y * sin(t), ray1.d.x * sin(t) + ray1.d.y * cos(t));
+	ray2.d.xy = vec2( ray2.d.x  *cos(t) - ray2.d.y * sin(t), ray2.d.x * sin(t) + ray2.d.y * cos(t));
+
+	float m1 =  mandelbulb(ray1.o + ray1.d, abs(cos(t)*13.0));
+	float m2 =  mandelbulb(ray2.o + ray2.d, abs(sin(t)*13.0));
+
+	float f = pow(max(m1,m2) , abs(m1-m2));
+	vec3  c = m1 > m2 ? vec3(0.0, 0.05, 0.2) : vec3(0.2, 0.05, 0.0);
+
+	gl_FragColor = vec4(c*f, 1.0);
+}
+