/// <summary>
/// Loads a compressed DDS file into an OpenGL texture.
/// </summary>
/// <param name="ResourceFile">The path to the DDS file.</param>
private void LoadDDS(string ResourceFile)
{
using (BinaryReader stream = new BinaryReader(new FileStream(ResourceFile, FileMode.Open)))
{
string filecode = new string(stream.ReadChars(4));
if (filecode != "DDS ") // first 4 chars should be "DDS "
{
throw new Exception("File was not a DDS file format.");
}
DDS.DDSURFACEDESC2 imageData = new DDS.DDSURFACEDESC2(stream); // read the DirectDraw surface descriptor
this.Size = new Size((int)imageData.Width, (int)imageData.Height);
if (imageData.LinearSize == 0)
{
throw new Exception("The linear scan line size was zero.");
}
bool compressed = true;
int factor = 0, buffersize = 0, blocksize = 0;
PixelInternalFormat format;
switch (imageData.PixelFormat.FourCC) // check the compression type
{
case "DXT1": // DXT1 compression ratio is 8:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt1Ext;
factor = 2;
blocksize = 8;
break;
case "DXT3": // DXT3 compression ratio is 4:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt3Ext;
factor = 4;
blocksize = 16;
break;
case "DXT5": // DXT5 compression ratio is 4:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt5Ext;
factor = 4;
blocksize = 16;
break;
default:
compressed = false;
if (imageData.PixelFormat.ABitMask == 0xf000 && imageData.PixelFormat.RBitMask == 0x0f00 &&
imageData.PixelFormat.GBitMask == 0x00f0 && imageData.PixelFormat.BBitMask == 0x000f &&
imageData.PixelFormat.RGBBitCount == 16)
{
format = PixelInternalFormat.Rgba;
}
throw new Exception(string.Format("File compression \"{0}\" is not supported.", imageData.PixelFormat.FourCC));
}
if (imageData.LinearSize != 0)
{
buffersize = (int)((imageData.MipmapCount > 1) ? imageData.LinearSize * factor : imageData.LinearSize);
}
else
{
buffersize = (int)(stream.BaseStream.Length - stream.BaseStream.Position);
}
// read the pixel data and then pin it to memory so that the garbage collector
// doesn't shuffle the data around while OpenGL is decompressing it
byte[] pixels = stream.ReadBytes(buffersize);
GCHandle pinned = GCHandle.Alloc(pixels, GCHandleType.Pinned);
try
{
this.TextureTarget = (imageData.Height == 1 || imageData.Width == 1) ? TextureTarget.Texture1D : TextureTarget.Texture2D;
this.TextureID = Gl.GenTexture();
Gl.BindTexture(TextureTarget, TextureID);
Gl.TexParameteri(TextureTarget, TextureParameterName.TextureMinFilter, TextureParameter.Linear);
Gl.TexParameteri(TextureTarget, TextureParameterName.TextureMagFilter, TextureParameter.Linear);
int nOffset = 0, nWidth = (int)imageData.Width, nHeight = (int)imageData.Height;
for (int i = 0; i < (imageData.MipmapCount == 0 ? 1 : imageData.MipmapCount); ++i)
{
if (nWidth == 0)
{
nWidth = 1; // smallest mipmap is 1x1 pixels
}
if (nHeight == 0)
{
nHeight = 1;
}
int nSize = 0;
if (compressed)
{
nSize = ((nWidth + 3) / 4) * ((nHeight + 3) / 4) * blocksize;
Gl.CompressedTexImage2D(TextureTarget, i, format, nWidth, nHeight, 0, nSize, (IntPtr)(pinned.AddrOfPinnedObject().ToInt64() + nOffset));
}
else
{
nSize = nWidth * nHeight * 4 * ((int)imageData.PixelFormat.RGBBitCount / 8);
Gl.TexImage2D(TextureTarget, i, format, nWidth, nHeight, 0, PixelFormat.Bgra, PixelType.UnsignedShort4444, (IntPtr)(pinned.AddrOfPinnedObject().ToInt64() + nOffset));
}
nOffset += nSize;
nWidth /= 2;
nHeight /= 2;
}
}
catch (Exception)
{ // There was some sort of Dll related error, or the target GPU does not support glCompressedTexImage2DARB
throw;
}
finally
{
pinned.Free();
}
}
}
/// <summary>
/// Loads a compressed DDS file into an OpenGL texture.
/// </summary>
/// <param name="ResourceFile">The path to the DDS file.</param>
private void LoadDDS(string ResourceFile)
{
using (BinaryReader stream = new BinaryReader(new FileStream(ResourceFile, FileMode.Open)))
{
string filecode = new string(stream.ReadChars(4));
if (filecode != "DDS ") // first 4 chars should be "DDS "
throw new Exception("File was not a DDS file format.");
DDS.DDSURFACEDESC2 imageData = new DDS.DDSURFACEDESC2(stream); // read the DirectDraw surface descriptor
this.Size = new Size((int)imageData.Width, (int)imageData.Height);
if (imageData.LinearSize == 0)
throw new Exception("The linear scan line size was zero.");
bool compressed = true;
int factor = 0, buffersize = 0, blocksize = 0;
PixelInternalFormat format;
switch (imageData.PixelFormat.FourCC) // check the compression type
{
case "DXT1": // DXT1 compression ratio is 8:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt1Ext;
factor = 2;
blocksize = 8;
break;
case "DXT3": // DXT3 compression ratio is 4:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt3Ext;
factor = 4;
blocksize = 16;
break;
case "DXT5": // DXT5 compression ratio is 4:1
format = PixelInternalFormat.CompressedRgbaS3tcDxt5Ext;
factor = 4;
blocksize = 16;
break;
default:
compressed = false;
if (imageData.PixelFormat.ABitMask == 0xf000 && imageData.PixelFormat.RBitMask == 0x0f00 &&
imageData.PixelFormat.GBitMask == 0x00f0 && imageData.PixelFormat.BBitMask == 0x000f &&
imageData.PixelFormat.RGBBitCount == 16) format = PixelInternalFormat.Rgba;
throw new Exception(string.Format("File compression \"{0}\" is not supported.", imageData.PixelFormat.FourCC));
}
if (imageData.LinearSize != 0) buffersize = (int)((imageData.MipmapCount > 1) ? imageData.LinearSize * factor : imageData.LinearSize);
else buffersize = (int)(stream.BaseStream.Length - stream.BaseStream.Position);
// read the pixel data and then pin it to memory so that the garbage collector
// doesn't shuffle the data around while OpenGL is decompressing it
byte[] pixels = stream.ReadBytes(buffersize);
GCHandle pinned = GCHandle.Alloc(pixels, GCHandleType.Pinned);
try
{
this.TextureTarget = (imageData.Height == 1 || imageData.Width == 1) ? TextureTarget.Texture1D : TextureTarget.Texture2D;
this.TextureID = Gl.GenTexture();
Gl.BindTexture(TextureTarget, TextureID);
Gl.TexParameteri(TextureTarget, TextureParameterName.TextureMinFilter, (int)TextureParam.Linear);
Gl.TexParameteri(TextureTarget, TextureParameterName.TextureMagFilter, (int)TextureParam.Linear);
int nOffset = 0, nWidth = (int)imageData.Width, nHeight = (int)imageData.Height;
for (int i = 0; i < (imageData.MipmapCount == 0 ? 1 : imageData.MipmapCount); ++i)
{
if (nWidth == 0) nWidth = 1; // smallest mipmap is 1x1 pixels
if (nHeight == 0) nHeight = 1;
int nSize = 0;
if (compressed)
{
nSize = ((nWidth + 3) / 4) * ((nHeight + 3) / 4) * blocksize;
Gl.CompressedTexImage2D(TextureTarget, i, format, nWidth, nHeight, 0, nSize, (IntPtr)(pinned.AddrOfPinnedObject().ToInt64() + nOffset));
}
else
{
nSize = nWidth * nHeight * 4 * ((int)imageData.PixelFormat.RGBBitCount / 8);
Gl.TexImage2D(TextureTarget, i, format, nWidth, nHeight, 0, PixelFormat.Bgra, PixelType.UnsignedShort4444, (IntPtr)(pinned.AddrOfPinnedObject().ToInt64() + nOffset));
}
nOffset += nSize;
nWidth /= 2;
nHeight /= 2;
}
}
catch (Exception)
{ // There was some sort of Dll related error, or the target GPU does not support glCompressedTexImage2DARB
throw;
}
finally
{
pinned.Free();
}
}
}