mirror of https://github.com/bkaradzic/bgfx
83 lines
1.4 KiB
Bash
83 lines
1.4 KiB
Bash
//
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// References:
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// Modeling with distance functions
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// http://www.iquilezles.org/www/articles/distfunctions/distfunctions.htm
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//
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// primitives
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float sdSphere(vec3 _pos, float _radius)
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{
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return length(_pos) - _radius;
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}
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float udBox(vec3 _pos, vec3 _extents)
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{
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return length(max(abs(_pos) - _extents, 0.0) );
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}
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float udRoundBox(vec3 _pos, vec3 _extents, float r)
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{
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return length(max(abs(_pos) - _extents, 0.0) ) - r;
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}
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float sdBox(vec3 _pos, vec3 _extents)
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{
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vec3 d = abs(_pos) - _extents;
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return min(max(d.x, max(d.y, d.z) ), 0.0) +
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length(max(d, 0.0) );
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}
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float sdTorus(vec3 _pos, vec2 t)
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{
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vec2 q = vec2(length(_pos.xz) - t.x, _pos.y);
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return length(q) - t.y;
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}
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float sdCylinder(vec3 _pos, vec3 c)
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{
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return length(_pos.xz - c.xy) - c.z;
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}
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float sdCone(vec3 _pos, vec2 c)
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{
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// c must be normalized
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float q = length(_pos.xy);
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return dot(c, vec2(q, _pos.z) );
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}
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float sdPlane(vec3 _pos, vec4 n)
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{
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// n must be normalized
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return dot(_pos, n.xyz) + n.w;
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}
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float sdHexPrism(vec3 _pos, vec2 h)
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{
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vec3 q = abs(_pos);
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return max(q.z - h.y, max(q.x + q.y * 0.57735, q.y * 1.1547) - h.x);
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}
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float sdTriPrism(vec3 _pos, vec2 h)
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{
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vec3 q = abs(_pos);
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return max(q.z - h.y, max(q.x * 0.866025 + _pos.y * 0.5, -_pos.y) - h.x * 0.5);
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}
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// domain operations
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float opUnion(float d1, float d2)
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{
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return min(d1, d2);
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}
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float opSubtract(float d1, float d2)
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{
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return max(-d1, d2);
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}
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float opIntersect(float d1, float d2)
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{
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return max(d1, d2);
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}
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