namespace blank {
-SimplexNoise::SimplexNoise(unsigned int seed)
+GaloisLFSR::GaloisLFSR(std::uint64_t seed) noexcept
+: state(seed) {
+
+}
+
+bool GaloisLFSR::operator ()() noexcept {
+ bool result = state & 1;
+ state >>= 1;
+ if (result) {
+ state |= 0x8000000000000000;
+ state ^= mask;
+ } else {
+ state &= 0x7FFFFFFFFFFFFFFF;
+ }
+ return result;
+}
+
+
+SimplexNoise::SimplexNoise(unsigned int seed) noexcept
: grad({
{ 1.0f, 1.0f, 0.0f },
{ -1.0f, 1.0f, 0.0f },
{ 0.0f, 1.0f, -1.0f },
{ 0.0f, -1.0f, -1.0f },
}) {
- unsigned int val = seed;
+ GaloisLFSR random(seed ^ 0x0123456789ACBDEF);
for (size_t i = 0; i < 256; ++i) {
- val = 2346765 * val + 6446345;
- perm[i] = val % 256;
+ random(perm[i]);
perm[i + 256] = perm[i];
+ perm12[i] = perm[i] % 12;
+ perm12[i + 256] = perm12[i];
}
}
-float SimplexNoise::operator ()(const glm::vec3 &in) const {
+float SimplexNoise::operator ()(const glm::vec3 &in) const noexcept {
float skew = (in.x + in.y + in.z) * one_third;
glm::vec3 skewed(glm::floor(in + skew));
(unsigned char)(skewed.y),
(unsigned char)(skewed.z),
};
- size_t corner[4] = {
- Perm(index[0] + Perm(index[1] + Perm(index[2]))),
- Perm(index[0] + second.x + Perm(index[1] + second.y + Perm(index[2] + second.z))),
- Perm(index[0] + third.x + Perm(index[1] + third.y + Perm(index[2] + third.z))),
- Perm(index[0] + 1 + Perm(index[1] + 1 + Perm(index[2] + 1))),
+ unsigned char corner[4] = {
+ Perm12(index[0] + Perm(index[1] + Perm(index[2]))),
+ Perm12(index[0] + int(second.x) + Perm(index[1] + int(second.y) + Perm(index[2] + int(second.z)))),
+ Perm12(index[0] + int(third.x) + Perm(index[1] + int(third.y) + Perm(index[2] + int(third.z)))),
+ Perm12(index[0] + 1 + Perm(index[1] + 1 + Perm(index[2] + 1))),
};
float n[4];
float t[4];
}
-unsigned char SimplexNoise::Perm(size_t idx) const {
+unsigned char SimplexNoise::Perm(size_t idx) const noexcept {
return perm[idx];
}
-const glm::vec3 &SimplexNoise::Grad(size_t idx) const {
- return grad[idx % 12];
+unsigned char SimplexNoise::Perm12(size_t idx) const noexcept {
+ return perm12[idx];
+}
+
+const glm::vec3 &SimplexNoise::Grad(unsigned char idx) const noexcept {
+ return grad[idx];
}
-WorleyNoise::WorleyNoise(unsigned int seed)
+WorleyNoise::WorleyNoise(unsigned int seed) noexcept
: seed(seed)
, num_points(8) {
}
-float WorleyNoise::operator ()(const glm::vec3 &in) const {
+float WorleyNoise::operator ()(const glm::vec3 &in) const noexcept {
glm::vec3 center = floor(in);
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) {
for (int x = -1; x <= 1; ++x) {
- glm::tvec3<int> cube(center.x + x, center.y + y, center.z + z);
+ glm::vec3 cube(center.x + x, center.y + y, center.z + z);
unsigned int cube_rand =
- (cube.x * 130223) ^
- (cube.y * 159899) ^
- (cube.z * 190717) ^
+ (unsigned(cube.x) * 130223) ^
+ (unsigned(cube.y) * 159899) ^
+ (unsigned(cube.z) * 190717) ^
seed;
for (int i = 0; i < num_points; ++i) {
glm::vec3 point(cube);
cube_rand = 190667 * cube_rand + 109807;
- point.x += float(cube_rand % 200000) / 200000.0f;
+ point.x += float(cube_rand % 262144) / 262144.0f;
cube_rand = 135899 * cube_rand + 189169;
- point.y += float(cube_rand % 200000) / 200000.0f;
+ point.y += float(cube_rand % 262144) / 262144.0f;
cube_rand = 159739 * cube_rand + 112139;
- point.z += float(cube_rand % 200000) / 200000.0f;
+ point.z += float(cube_rand % 262144) / 262144.0f;
glm::vec3 diff(in - point);
float distance = sqrt(dot(diff, diff));