internal static Image <T>[] GenerateMipmaps <T>(Image <T> baseImage) where T : struct, IPixel <T>
{
int mipLevelCount = MipmapHelper.ComputeMipLevels(baseImage.Width, baseImage.Height);
Image <T>[] mipLevels = new Image <T> [mipLevelCount];
mipLevels[0] = baseImage;
int i = 1;
int currentWidth = baseImage.Width;
int currentHeight = baseImage.Height;
while (currentWidth != 1 || currentHeight != 1)
{
int newWidth = Math.Max(1, currentWidth / 2);
int newHeight = Math.Max(1, currentHeight / 2);
Image <T> newImage = baseImage.Clone(context => context.Resize(newWidth, newHeight, KnownResamplers.Lanczos3));
Debug.Assert(i < mipLevelCount);
mipLevels[i] = newImage;
i++;
currentWidth = newWidth;
currentHeight = newHeight;
}
Debug.Assert(i == mipLevelCount);
return(mipLevels);
}
public ImageSharpTexture(Image <Rgba32> image, bool mipmap = true)
{
if (mipmap)
{
Images = MipmapHelper.GenerateMipmaps(image);
}
else
{
Images = new Image <Rgba32>[] { image };
}
}
public ImageSharpTexture(Image <Rgba32> image, bool mipmap, bool srgb)
{
Format = srgb ? PixelFormat.R8_G8_B8_A8_UNorm_SRgb : PixelFormat.R8_G8_B8_A8_UNorm;
if (mipmap)
{
Images = MipmapHelper.GenerateMipmaps(image);
}
else
{
Images = new Image <Rgba32>[] { image };
}
}
public ImageSharpCubemapTexture(
Image <Rgba32> positiveX,
Image <Rgba32> negativeX,
Image <Rgba32> positiveY,
Image <Rgba32> negativeY,
Image <Rgba32> positiveZ,
Image <Rgba32> negativeZ,
bool mipmap = true)
{
CubemapTextures = new Image <Rgba32> [6][];
if (mipmap)
{
CubemapTextures[0] = MipmapHelper.GenerateMipmaps(positiveX);
CubemapTextures[1] = MipmapHelper.GenerateMipmaps(negativeX);
CubemapTextures[2] = MipmapHelper.GenerateMipmaps(positiveY);
CubemapTextures[3] = MipmapHelper.GenerateMipmaps(negativeY);
CubemapTextures[4] = MipmapHelper.GenerateMipmaps(positiveZ);
CubemapTextures[5] = MipmapHelper.GenerateMipmaps(negativeZ);
}
else
{
CubemapTextures[0] = new Image <Rgba32>[1] {
positiveX
};
CubemapTextures[1] = new Image <Rgba32>[1] {
negativeX
};
CubemapTextures[2] = new Image <Rgba32>[1] {
positiveY
};
CubemapTextures[3] = new Image <Rgba32>[1] {
negativeY
};
CubemapTextures[4] = new Image <Rgba32>[1] {
positiveZ
};
CubemapTextures[5] = new Image <Rgba32>[1] {
negativeZ
};
}
}
