private Bitmap NoiseTexture(int octaves, double persistence, double initFrequency, double initAmplitude)
{
Bitmap finalNoise = new Bitmap(Heightmap.Instance.Width, Heightmap.Instance.Height, PixelFormat.Format24bppRgb);
BitmapData finalDataNoise = finalNoise.LockBits(new Rectangle(0, 0, finalNoise.Width, finalNoise.Height),
ImageLockMode.WriteOnly, finalNoise.PixelFormat);
byte[] finalRawData = new byte[finalDataNoise.Height * finalDataNoise.Stride];
Marshal.Copy(finalDataNoise.Scan0, finalRawData, 0, finalDataNoise.Height * finalDataNoise.Stride);
// write noise
AForge.Math.PerlinNoise noise = new AForge.Math.PerlinNoise(octaves, persistence, initFrequency, initAmplitude);
int height = finalDataNoise.Height, width = finalDataNoise.Width, stride = finalDataNoise.Stride;
Parallel.For(0, height, i =>
{
for (int j = 0; j < width; j++)
{
var value = (byte)(Math.Max(0.0f, Math.Min(1.0f, (float)noise.Function2D(i, j) * 0.5f + 0.5f)) * 255);
value = (byte)((value < 0) ? 0 : (value > 255) ? 255 : value);
finalRawData[i * stride + j * 3] = value;
finalRawData[i * stride + j * 3 + 1] = value;
finalRawData[i * stride + j * 3 + 2] = value;
}
});
Marshal.Copy(finalRawData, 0, finalDataNoise.Scan0, finalRawData.Length);
finalNoise.UnlockBits(finalDataNoise);
return(finalNoise);
}
public void PerlinNoise(int octaves, double persistence, double initFrequency, double initAmplitude, bool threaded)
{
LockForWriting();
// reserve for texture values
if (_dimensionsChanged)
{
MapValues = new byte[_height * _stride];
}
// not ready for writing
if (MapValues == null || !_bitsLocked)
{
return;
}
// subdivide work betweek threads
if (threaded)
{
// thread work subdivitions
int subDivs = (int)Math.Ceiling((double)_height / (Environment.ProcessorCount - 1));
// perlin function
Perlin = new AForge.Math.PerlinNoise(octaves, persistence, initFrequency, initAmplitude);
// assign work to threads
for (int i = 0; i < Environment.ProcessorCount - 1; i++)
{
int startIndex = i * subDivs;
int endIndex = Math.Min(startIndex + subDivs, _height);
// fire up threads
_perlinWorker[i] = new Thread(() => CalculateSection(startIndex, endIndex));
_perlinWorker[i].Start();
}
// wait for all threads to finish
for (int i = 0; i < Environment.ProcessorCount - 1; i++)
{
_perlinWorker[i].Join();
}
}
else
{
// perlin function
Perlin = new AForge.Math.PerlinNoise(octaves, persistence, initFrequency, initAmplitude);
// assign perlin noise value per pixel
for (int i = 0; i < _height; i++)
{
for (int j = 0; j < _width; j++)
{
var value = Math.Max(0.0f, Math.Min(1.0, (double)Perlin.Function2D((double)i, (double)j) * 0.5 + 0.5));
// from 0.0 - 1.0 to 0 - 255 byte data
value = value * 255;
// assign values at rgb positions
this[i, j] = (byte)value;
}
}
}
CopyToTexture();
Unlock();
}