BeRo1985
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December 3, 2023 05:01
GLSL Octahedral Texture Mapping with Edge Mirroring and Bilinear Interpolation
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| // GLSL Octahedral Texture Mapping with Edge Mirroring and Bilinear Interpolation (by Benjamin 'BeRo' Rosseaux) | |
| ivec2 wrapOctahedralTexelCoordinates(const in ivec2 texel, const in ivec2 texSize) { | |
| ivec2 wrapped = ((texel % texSize) + texSize) % texSize; | |
| return ((((abs(texel.x / texSize.x) + int(texel.x < 0)) ^ (abs(texel.y / texSize.y) + int(texel.y < 0))) & 1) != 0) ? (texSize - (wrapped + ivec2(1))) : wrapped; | |
| } | |
| vec4 textureOctahedralMap(const in sampler2D tex, vec3 direction) { | |
| direction = normalize(direction); // just for to make sure that it is normalized | |
| vec2 uv = direction.xy / (abs(direction.x) + abs(direction.y) + abs(direction.z)); |