private void InitWithKTXTexture(BinaryReader reader)
{
var identifier = reader.ReadBytes(12);
if (identifier[1] != 'K' || identifier[2] != 'T' || identifier[3] != 'X')
{
throw new InvalidDataException("Invalid KTX header");
}
var endiannes = reader.ReadUInt32();
if (endiannes != 0x04030201)
{
throw new InvalidDataException("Unsupported endiannes");
}
var glType = reader.ReadInt32();
var glTypeSize = reader.ReadInt32();
var glFormat = reader.ReadInt32();
var glInternalFormat = reader.ReadInt32();
var glBaseInternalFormat = reader.ReadInt32();
var pixelWidth = reader.ReadInt32();
var pixelHeight = reader.ReadInt32();
var pixelDepth = reader.ReadInt32();
var numberOfArrayElements = reader.ReadInt32();
var numberOfFaces = reader.ReadInt32();
var numberOfMipmapLevels = reader.ReadInt32();
var bytesOfKeyValueData = reader.ReadInt32();
reader.ReadBytes(bytesOfKeyValueData);
if (numberOfArrayElements != 0)
{
throw new InvalidDataException("Array textures are not supported");
}
if (numberOfFaces != 1)
{
throw new InvalidDataException("Cubemap textures are not supported");
}
if (pixelDepth != 0)
{
throw new InvalidDataException("3D Textures are not supported");
}
if ((pixelWidth & 3) != 0 || (pixelHeight & 3) != 0)
{
throw new InvalidDataException("Texture dimensions should multiple of 4");
}
SurfaceSize = ImageSize = new Size(pixelWidth, pixelHeight);
Action glCommands = PrepareOpenGLTexture;
PrepareOpenGLTexture();
for (int i = 0; i < Math.Max(1, numberOfMipmapLevels); i++)
{
var dataLength = reader.ReadInt32();
MemoryUsed = 0;
if (i > 0 && (pixelWidth < 8 || pixelHeight < 8))
{
continue;
}
// Copy variables because they will be captured.
int mipLevel = i;
int width = pixelWidth;
int height = pixelHeight;
if (glFormat == 0)
{
var data = ReadTextureData(reader, dataLength);
glCommands += () => {
if (!etc2Checked)
{
etc2Checked = true;
if (PlatformRenderer.GetGLESMajorVersion() >= 3)
{
etc2Supported = true;
}
else
{
var ext = GL.GetString(StringName.Extensions);
etc2Supported = ext?.Contains("ETC2_RGBA8") ?? false;
}
Debug.Write(etc2Supported ? "ETC2 textures supported." : "ETC2 textures not supported.");
}
PlatformRenderer.PushTexture(handle, 0);
const int etc1Rgb8Oes = 36196;
if (etc2Supported || (Application.Platform == PlatformId.Android && glInternalFormat == etc1Rgb8Oes))
{
GL.CompressedTexImage2D(
TextureTarget.Texture2D, mipLevel, (PixelInternalFormat)glInternalFormat,
width, height, 0, dataLength, data);
}
else
{
var rgba8Data = Marshal.AllocHGlobal(width * height * 4);
Etc2Decoder.Decode(data, rgba8Data, width, height, glInternalFormat);
GL.TexImage2D(TextureTarget.Texture2D, mipLevel, PixelInternalFormat.Rgba, width, height, 0, PixelFormat.Rgba, PixelType.UnsignedByte, rgba8Data);
Marshal.FreeHGlobal(rgba8Data);
}
PlatformRenderer.PopTexture(0);
PlatformRenderer.CheckErrors();
};
}
else
{
var data = ReadTextureData(reader, dataLength);
glCommands += () => {
PlatformRenderer.PushTexture(handle, 0);
GL.TexImage2D(
TextureTarget.Texture2D, mipLevel, (PixelInternalFormat)glInternalFormat,
width, height, 0, (PixelFormat)glFormat, (PixelType)glType, data);
PlatformRenderer.PopTexture(0);
PlatformRenderer.CheckErrors();
};
}
pixelWidth /= 2;
pixelHeight /= 2;
}
Application.InvokeOnMainThread(glCommands);
}