GenVect PerlinNoise2D::generate(size_t xn, size_t yn)
{
GenVect generation = GenVect(xn);
GenVect result = GenVect(xn);
for (size_t x = 0; x < xn; x++)
{
generation[x] = randomNoise(yn);
result[x] = generation[x];
}
for (size_t i = 0; i < depth; i++)
{
GenVect nextGen = GenVect(xn);
for (size_t x = 0; x < xn; x++)
{
nextGen[x] = std::vector<float>(yn);
for (size_t y = 0; y < yn; y++)
{
int x1 = _perlin_noise2d::floor(x / 2.0f);
int x2 = _perlin_noise2d::ceil(x / 2.0f);
int y1 = _perlin_noise2d::floor(y / 2.0f);
int y2 = _perlin_noise2d::ceil(y / 2.0f);
nextGen[x][y] = generation[x1][y1] + generation[x2][y2];
result[x][y] += nextGen[x][y];
}
}
generation = nextGen;
}
return result;
}
int main(void)
{
cv :: Mat randomNoise(numTrainingPoints, numVariables, CV_32FC1 );
cv :: randu (randomNoise, 0., 1.) ;
//the Mat file randomNoise is now filled with uniformly
//distributed random numbers between 0 and 1.
cv::imshow("random noise", randomNoise);
cv::waitKey(0);
}
void NoiseProcessor::perlinNoise(Image *img) {
auto size = nextPow2(std::max(size_.get().x, size_.get().y));
std::vector<std::unique_ptr<Image>> levels;
std::vector<TemplateImageSampler<float,float>> samplers;
auto currentSize = std::pow(2, levels_.get().x);
auto iterations = levels_.get().y - levels_.get().x + 1;
float currentPersistance = 1;
while (currentSize <= size && iterations--) {
size2_t imgsize{static_cast<size_t>(currentSize)};
auto img1 = util::make_unique<Image>(imgsize, DataFLOAT32::get());
randomNoise(img1.get(), -currentPersistance, currentPersistance);
samplers.push_back(TemplateImageSampler<float,float>(img1.get()));
levels.push_back(std::move(img1));
currentSize *= 2;
currentPersistance *= persistence_.get();
}
auto data = static_cast<float *>(
img->getColorLayer()->getEditableRepresentation<LayerRAM>()->getData());
float repri = 1.0 / size;
// size_t index = 0;
util::IndexMapper2D index(size_.get());
#pragma omp parallel for
for (long long y = 0; y < size_.get().y; y++) {
for (long long x = 0; x < size_.get().x; x++) {
float v = 0;
float X = x * repri;
float Y = y * repri;
for (auto &sampler : samplers) {
v += sampler.sample(X, Y);
}
v = (v + 1.0f) / 2.0f;
data[index(x, size_.get().y - 1 - y)] = glm::clamp(v, 0.0f, 1.0f);
}
}
}