precision highp float; uniform vec2 resolution; uniform float time; uniform vec2 mouse; uniform sampler2D backbuffer; #define AA 2 const int numIterations = 11; vec4 qsqr( in vec4 a ) { return vec4( a.x*a.x - a.y*a.y - a.z*a.z - a.w*a.w, 2.0*a.x*a.y, 2.0*a.x*a.z, 2.0*a.x*a.w ); } vec4 qmul( in vec4 a, in vec4 b) { return vec4( a.x * b.x - a.y * b.y - a.z * b.z - a.w * b.w, a.y * b.x + a.x * b.y + a.z * b.w - a.w * b.z, a.z * b.x + a.x * b.z + a.w * b.y - a.y * b.w, a.w * b.x + a.x * b.w + a.y * b.z - a.z * b.y ); } vec4 qconj( in vec4 a ) { return vec4( a.x, -a.yzw ); } float qlength2( in vec4 q ) { return dot(q,q); } float map( in vec3 p, out vec4 oTrap, in vec4 c ) { vec4 z = vec4(p,0.0); float md2 = 1.0; float mz2 = dot(z,z); vec4 trap = vec4(abs(z.xyz),dot(z,z)); float n = 1.0; for( int i=0; i4.0) break; n += 1.0; } oTrap = trap; return 0.25*sqrt(mz2/md2)*log(mz2); } vec3 calcNormal( in vec3 p, in vec4 c ) { vec4 z = vec4(p,0.0); vec4 J0 = vec4(1,0,0,0); vec4 J1 = vec4(0,1,0,0); vec4 J2 = vec4(0,0,1,0); for (int i=0; i4.0) break; } vec3 v = vec3(dot(J0,z), dot(J1,z), dot(J2,z)); return normalize( v ); } float intersect( in vec3 ro, in vec3 rd, out vec4 res, in vec4 c ) { vec4 tmp; float resT = -1.0; float maxd = 10.0; float h = 1.0; float t = 0.0; for( int i=0; i<300; i++ ) { if( h<0.0001||t>maxd ) break; h = map( ro+rd*t, tmp, c ); t += h; } if( t

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