port from perforce

hgplus/ShaderMinifier/tests/real/chocolux.frag

@@ -0,0 +1,43 @@
+uniform vec2 resolution;
+uniform float time;
+
+float h(vec3 q)
+{
+    float f=1.*distance(q,vec3(cos(time)+sin(time*.2),.3,2.+cos(time*.5)*.5));
+    f*=distance(q,vec3(-cos(time*.7),.3,2.+sin(time*.5)));
+    f*=distance(q,vec3(-sin(time*.2)*.5,sin(time),2.));
+    f*=cos(q.y)*cos(q.x)-.1-cos(q.z*7.+time*7.)*cos(q.x*3.)*cos(q.y*4.)*.1;
+    return f;
+}
+
+void main()
+{
+    vec2 p = -1.0 + 2.0 * gl_FragCoord.xy / resolution.xy;
+    vec3 o=vec3(p.x,p.y*1.25-0.3,0.);
+    vec3 d=vec3(p.x+cos(time)*0.3,p.y,1.)/64.;
+    vec4 c=vec4(0.);
+    float t=0.;
+    for(int i=0;i<75;i++)
+    {
+        if(h(o+d*t)<.4)
+        {
+            t-=5.;
+            for(int j=0;j<5;j++)
+            {
+                if(h(o+d*t)<.4)
+                    break;
+                t+=1.;
+            }
+            vec3 e=vec3(.01,.0,.0);
+            vec3 n=vec3(.0);
+            n.x=h(o+d*t)-h(vec3(o+d*t+e.xyy));
+            n.y=h(o+d*t)-h(vec3(o+d*t+e.yxy));
+            n.z=h(o+d*t)-h(vec3(o+d*t+e.yyx));
+            n=normalize(n);
+            c+=max(dot(vec3(.0,.0,-.5),n),.0)+max(dot(vec3(.0,-.5,.5),n),.0)*.5;
+            break;
+        }
+        t+=5.;
+    }
+    gl_FragColor=c+vec4(.1,.2,.5,1.)*(t*.025);
+}