/// <summary>
/// Resizes the specified texture and/or generates mipmaps.
/// </summary>
/// <param name="texture">The texture.</param>
/// <param name="width">The desired width.</param>
/// <param name="height">The desired height.</param>
/// <param name="inputGamma">The input gamma.</param>
/// <param name="outputGamma">The output gamma.</param>
/// <param name="generateMipmaps">
/// <see langword="true"/> to generate all mipmap levels; otherwise <see langword="false"/>.
/// </param>
/// <param name="hasAlpha">
/// <see langword="true"/> if <paramref name="texture"/> requires an alpha channel; otherwise,
/// <see langword="false"/> if <paramref name="texture"/> is opaque.
/// </param>
/// <param name="hasFractionalAlpha">
/// <see langword="true"/> if <paramref name="texture"/> contains fractional alpha values;
/// otherwise, <see langword="false"/> if <paramref name="texture"/> is opaque or contains only
/// binary alpha.
/// </param>
/// <param name="premultipliedAlpha">
/// <see langword="true"/> when <paramref name="texture"/> is using premultiplied alpha.;
/// otherwise, <see langword="false"/>.</param>
/// <returns>The resized texture.</returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="texture"/> is <see langword="null"/>.
/// </exception>
public static Texture ResizeAndGenerateMipmaps(Texture texture, int width, int height, float inputGamma, float outputGamma, bool generateMipmaps, bool hasAlpha, bool hasFractionalAlpha, bool premultipliedAlpha)
{
if (texture == null)
throw new ArgumentNullException("texture");
// NVIDIA Texture Tools expect BGRA 8:8:8:8.
if (texture.Description.Format != TextureFormat.B8G8R8A8_UNorm)
throw new ArgumentException("Texture format needs to be B8G8R8A8_UNORM.", "texture");
if (texture.Description.Dimension != TextureDimension.TextureCube && texture.Description.ArraySize > 1)
throw new NotSupportedException("Resizing and mipmap generation for texture arrays is not supported.");
if (texture.Description.Dimension == TextureDimension.Texture3D)
throw new NotSupportedException("Resizing and mipmap generation for volume textures is not supported.");
// ----- InputOptions
var inputOptions = new InputOptions();
inputOptions.SetAlphaMode(hasAlpha ? (premultipliedAlpha ? AlphaMode.Premultiplied : AlphaMode.Transparency)
: AlphaMode.None);
inputOptions.SetFormat(InputFormat.BGRA_8UB);
inputOptions.SetGamma(inputGamma, outputGamma);
inputOptions.SetMipmapFilter(MipmapFilter.Box);
inputOptions.SetMipmapGeneration(generateMipmaps);
bool roundToPowerOfTwo = (width != texture.Description.Width || height != texture.Description.Height);
inputOptions.SetRoundMode(roundToPowerOfTwo ? RoundMode.ToNextPowerOfTwo : RoundMode.None);
inputOptions.SetWrapMode(WrapMode.Mirror);
var description = texture.Description;
bool isCube = description.Dimension == TextureDimension.TextureCube;
var textureType = isCube ? TextureType.TextureCube : TextureType.Texture2D;
inputOptions.SetTextureLayout(textureType, description.Width, description.Height, 1);
for (int arrayIndex = 0; arrayIndex < description.ArraySize; arrayIndex++)
{
for (int mipIndex = 0; mipIndex < description.MipLevels; mipIndex++)
{
int index = texture.GetImageIndex(mipIndex, arrayIndex, 0);
var image = texture.Images[index];
var handle = GCHandle.Alloc(image.Data, GCHandleType.Pinned);
inputOptions.SetMipmapData(handle.AddrOfPinnedObject(), image.Width, image.Height, 1, arrayIndex, mipIndex);
handle.Free();
}
}
// ----- OutputOptions
var outputOptions = new OutputOptions();
outputOptions.SetOutputHeader(false);
outputOptions.Error += OnError;
description.Format = TextureFormat.R8G8B8A8_UNorm;
description.Width = width;
description.Height = height;
description.MipLevels = generateMipmaps ? CalculateMipLevels(width, height) : 1;
var resizedTexture = new Texture(description);
var outputHandler = new OutputHandler(resizedTexture);
outputOptions.SetOutputHandler(outputHandler.BeginImage, outputHandler.WriteData);
// ----- CompressionOptions
var compressionOptions = new CompressionOptions();
compressionOptions.SetFormat(Format.RGBA);
compressionOptions.SetPixelFormat(32, 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000);
compressionOptions.SetQuality(Quality.Normal);
// ----- Run NVTT
try
{
var compressor = new Compressor();
compressor.Compress(inputOptions, compressionOptions, outputOptions);
}
catch (NullReferenceException)
{
// Resizing and mipmap generation without compression sometimes causes a
// NullReferenceException in nvttCompress().
throw new Exception("NullReferenceException in NVIDIA texture tools. Please try again.");
}
return resizedTexture;
}
/// <summary>
/// Compresses the specified texture using a Block Compression format (BC<i>n</i>).
/// </summary>
/// <param name="texture">The uncompressed texture.</param>
/// <param name="inputGamma">The input gamma.</param>
/// <param name="outputGamma">The output gamma.</param>
/// <param name="generateMipmaps">
/// <see langword="true"/> to generate all mipmap levels; otherwise <see langword="false"/>.
/// </param>
/// <param name="hasAlpha">
/// <see langword="true"/> if <paramref name="texture"/> requires an alpha channel; otherwise,
/// <see langword="false"/> if <paramref name="texture"/> is opaque.
/// </param>
/// <param name="hasFractionalAlpha">
/// <see langword="true"/> if <paramref name="texture"/> contains fractional alpha values;
/// otherwise, <see langword="false"/> if <paramref name="texture"/> is opaque or contains only
/// binary alpha.
/// </param>
/// <param name="premultipliedAlpha">
/// <see langword="true"/> when <paramref name="texture"/> is using premultiplied alpha.;
/// otherwise, <see langword="false"/>.</param>
/// <param name="sharpAlpha">
/// <see langword="true"/> when the texture contains a sharp alpha mask; otherwise
/// <see langword="false"/>.
/// </param>
/// <returns>The compressed texture.</returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="texture"/> is <see langword="null"/>.
/// </exception>
/// <exception cref="ArgumentException">
/// Texture width and height need to be equal (square texture) and a power of two (POT
/// texture).
/// </exception>
internal static Texture CompressBCn(Texture texture, float inputGamma, float outputGamma, bool generateMipmaps, bool hasAlpha, bool hasFractionalAlpha, bool premultipliedAlpha, bool sharpAlpha = false)
{
if (texture == null)
throw new ArgumentNullException("texture");
if (texture.Description.Dimension == TextureDimension.Texture3D)
throw new NotSupportedException("Texture compression for volume textures is not supported.");
// NVIDIA Texture Tools expect BGRA 8:8:8:8.
texture = texture.ConvertTo(TextureFormat.B8G8R8A8_UNorm);
// ----- InputOptions
var inputOptions = new InputOptions();
inputOptions.SetAlphaMode(hasAlpha ? (premultipliedAlpha ? AlphaMode.Premultiplied : AlphaMode.Transparency)
: AlphaMode.None);
inputOptions.SetFormat(InputFormat.BGRA_8UB);
inputOptions.SetGamma(inputGamma, outputGamma);
inputOptions.SetMipmapFilter(MipmapFilter.Box);
inputOptions.SetMipmapGeneration(generateMipmaps);
inputOptions.SetRoundMode(RoundMode.None); // Size is set explicitly.
inputOptions.SetWrapMode(WrapMode.Mirror);
var description = texture.Description;
bool isCube = description.Dimension == TextureDimension.TextureCube;
var textureType = isCube ? TextureType.TextureCube : TextureType.Texture2D;
inputOptions.SetTextureLayout(textureType, description.Width, description.Height, 1);
for (int arrayIndex = 0; arrayIndex < description.ArraySize; arrayIndex++)
{
for (int mipIndex = 0; mipIndex < description.MipLevels; mipIndex++)
{
int index = texture.GetImageIndex(mipIndex, arrayIndex, 0);
var image = texture.Images[index];
var handle = GCHandle.Alloc(image.Data, GCHandleType.Pinned);
inputOptions.SetMipmapData(handle.AddrOfPinnedObject(), image.Width, image.Height, 1, arrayIndex, mipIndex);
handle.Free();
}
}
// ----- OutputOptions
var outputOptions = new OutputOptions();
outputOptions.SetOutputHeader(false);
outputOptions.Error += OnError;
Format compressedFormat;
if (hasAlpha)
{
if (sharpAlpha)
{
compressedFormat = Format.BC2;
description.Format = TextureFormat.BC2_UNorm;
}
else
{
compressedFormat = Format.BC3;
description.Format = TextureFormat.BC3_UNorm;
}
}
else
{
compressedFormat = Format.BC1;
description.Format = TextureFormat.BC1_UNorm;
}
var compressedTexture = new Texture(description);
var outputHandler = new OutputHandler(compressedTexture);
outputOptions.SetOutputHandler(outputHandler.BeginImage, outputHandler.WriteData);
// ----- CompressionOptions
var compressionOptions = new CompressionOptions();
compressionOptions.SetFormat(compressedFormat);
compressionOptions.SetQuality(Quality.Normal);
// ----- Run NVTT
try
{
var compressor = new Compressor();
compressor.Compress(inputOptions, compressionOptions, outputOptions);
}
catch (NullReferenceException)
{
throw new Exception("NullReferenceException in NVIDIA texture tools. Please try again.");
}
return compressedTexture;
}
