Add KTX1 texture container support with spec-compliant reader

nel/include/nel/misc/bitmap.h

@@ -48,6 +48,7 @@ const uint32	DXT_HEADER = NL_MAKEFOURCC('D', 'X', 'T', '\0');
 const uint32	PNG_HEADER = NL_MAKEFOURCC(0x89, 'P', 'N', 'G');
 const uint32	JPG_HEADER = NL_MAKEFOURCC(0xff, 0xd8, 0xff, 0xe0);
 const uint32	GIF_HEADER = NL_MAKEFOURCC('G', 'I', 'F', '8');
+const uint32	KTX_HEADER = NL_MAKEFOURCC(0xAB, 'K', 'T', 'X');
 
 
 // dwLinearSize is valid
@@ -145,6 +146,16 @@ private :
 	uint8 readGIF( NLMISC::IStream &f );
 
 
+	/**
+	 * Read a KTX1 from an IStream.
+	 * KTX files can contain compressed (DXTC) or uncompressed texture data.
+	 * \param f IStream (must be a reading stream)
+	 * \param mipMapSkip number of mipmaps to skip
+	 * \return image depth if succeed, 0 else
+	 */
+	uint8 readKTX( NLMISC::IStream &f, uint mipMapSkip );
+
+
 	/**
 	 * Change bitmap format
 	 *
@@ -330,21 +341,23 @@ private :
 	void	swap(CBitmap &other);
 
 	/**
-	 * Read a bitmap(TGA, JPEG, PNG or DDS) from an IStream.
-	 * Bitmap supported are DDS (DXTC1, DXTC1 with Alpha, DXTC3, DXTC5), PNG, JPEG and
-	 * uncompressed TGA (24 and 32 bits).
+	 * Read a bitmap(TGA, JPEG, PNG, DDS or KTX) from an IStream.
+	 * Bitmap supported are DDS (DXTC1, DXTC1 with Alpha, DXTC3, DXTC5),
+	 * KTX (DXTC1, DXTC3, DXTC5, RGBA, Luminance, Alpha),
+	 * PNG, JPEG and uncompressed TGA (24 and 32 bits).
 	 * \param IStream The stream must be in reading mode.
-	 * \param mipMapSkip if the file is a DDS with mipMap. N=mipMapSkip mipmaps are skipped.
+	 * \param mipMapSkip if the file is a DDS or KTX with mipMap. N=mipMapSkip mipmaps are skipped.
 	 * \return image depth (24 or 32), or 0 if load failed
 	 * \throw ESeekFailed : seek has failed
 	 */
 	uint8	load(NLMISC::IStream &f, uint mipMapSkip=0);
 
 
 	/**
-	 * Determinate the bitmap size from a bitmap(TGA or DDS) from an IStream. load just header of the file.
-	 * Bitmap supported are DDS (DXTC1, DXTC1 with Alpha, DXTC3, DXTC5), PNG, JPEG and
-	 * uncompressed TGA (24 and 32 bits).
+	 * Determinate the bitmap size from a bitmap(TGA, DDS or KTX) from an IStream. load just header of the file.
+	 * Bitmap supported are DDS (DXTC1, DXTC1 with Alpha, DXTC3, DXTC5),
+	 * KTX (DXTC1, DXTC3, DXTC5, RGBA, Luminance, Alpha),
+	 * PNG, JPEG and uncompressed TGA (24 and 32 bits).
 	 * NB: at the end, f is seeked to begin.
 	 * \param IStream The stream must be in reading mode.
 	 * \param width the width of the image. 0 if fails.

nel/src/misc/bitmap.cpp

@@ -165,6 +165,17 @@ uint8 CBitmap::load(NLMISC::IStream &f, uint mipMapSkip)
 	}
 #endif // USE_GIF
 
+	if (fileType == KTX_HEADER)
+	{
+#ifdef NEL_ALL_BITMAP_WHITE
+		uint8 result = readKTX(f, mipMapSkip);
+		MakeWhite (*this);
+		return result;
+#else // NEL_ALL_BITMAP_WHITE
+		return readKTX(f, mipMapSkip);
+#endif // NEL_ALL_BITMAP_WHITE
+	}
+
 	// assuming it's TGA
 	NLMISC::IStream::TSeekOrigin origin= f.begin;
 	if(!f.seek (0, origin))
@@ -3667,6 +3678,34 @@ void	CBitmap::loadSize(NLMISC::IStream &f, uint32 &retWidth, uint32 &retHeight)
 		retWidth = lsWidth;
 		retHeight = lsHeight;
 	}
+	else if(fileType == KTX_HEADER)
+	{
+		// skip remaining 8 bytes of KTX identifier
+		f.seek(8, IStream::current);
+
+		// read endianness indicator using raw read (KTX has its own endianness handling)
+		uint32 endianness;
+		f.serialBuffer((uint8 *)&endianness, 4);
+		bool mustSwap = (endianness == 0x01020304);
+
+		// skip glType, glTypeSize, glFormat, glInternalFormat, glBaseInternalFormat (5 uint32s)
+		f.seek(5 * 4, IStream::current);
+
+		// read pixelWidth and pixelHeight using raw reads
+		uint32 w, h;
+		f.serialBuffer((uint8 *)&w, 4);
+		f.serialBuffer((uint8 *)&h, 4);
+
+		if (mustSwap)
+		{
+			NLMISC_BSWAP32(w);
+			NLMISC_BSWAP32(h);
+		}
+
+		retWidth = w;
+		// Per spec: pixelHeight 0 means 1D texture, treat as height 1
+		retHeight = (h == 0) ? 1 : h;
+	}
 	// assuming it's TGA
 	else
 	{