/// <summary>
/// Create the mipmaps by downsampling using a filter.
/// </summary>
public void GenerateMipmaps(Filter filter)
{
for (int i = 1; i < Levels; i++)
{
TextureData2D src = Data[i - 1];
TextureData2D dst = Data[i];
int srcWidth = src.GetWidth();
int srcHeight = src.GetHeight();
int dstWidth = dst.GetWidth();
int dstHeight = dst.GetHeight();
float[] tmp = new float[dstWidth * srcHeight * Channels];
PolyphaseKernel xKernel = new PolyphaseKernel(filter, srcWidth, dstWidth, 32);
PolyphaseKernel yKernel = new PolyphaseKernel(filter, srcHeight, dstHeight, 32);
for (int y = 0; y < srcHeight; y++)
{
xKernel.ApplyHorizontal(y, src, tmp, dstWidth);
}
for (int x = 0; x < dstWidth; x++)
{
yKernel.ApplyVertical(x, tmp, dstWidth, srcHeight, Channels, dst);
}
}
}
