X-Git-Url: http://git.localhorst.tv/?a=blobdiff_plain;f=src%2Fnoise.cpp;h=6d59224c2f41f4de89ae982627387fcacd7235a2;hb=e74f1ad236429f05db90c0ace825277e2a3fbc05;hp=4400a1a4988e0b57aee77e7d6b7ae73a522a4441;hpb=42dea80c2cffb75a5721d1cbf0cdd6277f4d520d;p=blank.git diff --git a/src/noise.cpp b/src/noise.cpp index 4400a1a..6d59224 100644 --- a/src/noise.cpp +++ b/src/noise.cpp @@ -12,6 +12,24 @@ constexpr float one_sixth = 1.0f/6.0f; namespace blank { +GaloisLFSR::GaloisLFSR(std::uint64_t seed) +: state(seed) { + +} + +bool GaloisLFSR::operator ()() { + bool result = state & 1; + state >>= 1; + if (result) { + state |= 0x8000000000000000; + state ^= mask; + } else { + state &= 0x7FFFFFFFFFFFFFFF; + } + return result; +} + + SimplexNoise::SimplexNoise(unsigned int seed) : grad({ { 1.0f, 1.0f, 0.0f }, @@ -119,7 +137,7 @@ WorleyNoise::WorleyNoise(unsigned int seed) float WorleyNoise::operator ()(const glm::vec3 &in) const { glm::vec3 center = floor(in); - float closest = 4.0f; + float closest = 1.0f; // cannot be farther away than 1.0 for (int z = -1; z <= 1; ++z) { for (int y = -1; y <= 1; ++y) { @@ -141,7 +159,7 @@ float WorleyNoise::operator ()(const glm::vec3 &in) const { point.z += float(cube_rand % 200000) / 200000.0f; glm::vec3 diff(in - point); - float distance = dot(diff, diff); + float distance = sqrt(dot(diff, diff)); if (distance < closest) { closest = distance; } @@ -150,7 +168,9 @@ float WorleyNoise::operator ()(const glm::vec3 &in) const { } } - return closest; + // closest ranges (0, 1), so normalizing to (-1,1) is trivial + // though heavily biased towards lower numbers + return 2.0f * closest - 1.0f; } }