60 lines
921 B
GLSL
60 lines
921 B
GLSL
varying vec3 dir;
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float flr(vec3 p, float f)
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{
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return abs(f - p.y);
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}
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float sph(vec3 p, vec4 spr)
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{
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return length(spr.xyz - p) - spr.w;
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}
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float iso_tore(vec3 p, vec3 center, float r1, float r2)
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{
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p -= center;
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float xx = sqrt(p.x * p.x + p.z * p.z) - r1;
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float dist = sqrt(xx * xx + p.y * p.y) - r2;
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return mix(dist, dist, 0.9);
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}
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float scene(vec3 p)
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{
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float d = iso_tore(p, vec3(0,0,15), 2.0, 0.5);
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return d;
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}
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vec3 getN(vec3 p)
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{
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float eps = 0.01;
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return normalize(vec3(
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scene(p+vec3(eps,0,0))-scene(p-vec3(eps,0,0)),
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scene(p+vec3(0,eps,0))-scene(p-vec3(0,eps,0)),
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scene(p+vec3(0,0,eps))-scene(p-vec3(0,0,eps))
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));
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}
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void main()
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{
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float g,d = 0.0;
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vec3 p = vec3(0);
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vec3 ndir = normalize(dir);
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for(int i = 0; i < 64; i++)
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{
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d = scene(p);
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p = p + d * ndir;
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}
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if(d > 1.0)
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{
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gl_FragColor = vec4(1.0,0.0,0.0,1.0);
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return;
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}
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vec3 n = getN(p);
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gl_FragColor = vec4(n, 1.0);
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}
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