23 lines
603 B
Plaintext
23 lines
603 B
Plaintext
|
|
|
|
sampler3D noiseMap : $noiseMap;
|
|
|
|
//FIXME: Use a different number of octaves based on the shader quality settings?
|
|
|
|
|
|
half bandLimitedNoise( float3 P ) {
|
|
return tex3D( noiseMap, P ).x;
|
|
}
|
|
|
|
half perlin(float3 inpos) {
|
|
half4 octaveScales = { 0.5, 0.25, 0.125, 0.0625 };
|
|
half4 noiseSamples;
|
|
|
|
//FIXME: use inpos+inpos? is add still faster than a mul?
|
|
noiseSamples.x = bandLimitedNoise( inpos );
|
|
noiseSamples.y = bandLimitedNoise( inpos*2 );
|
|
noiseSamples.z = bandLimitedNoise( inpos*4 );
|
|
noiseSamples.w = bandLimitedNoise( inpos*8 );
|
|
|
|
return dot( noiseSamples, octaveScales );
|
|
} |