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diff --git a/thirdparty/squish/squish.cpp b/thirdparty/squish/squish.cpp
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+/* -----------------------------------------------------------------------------
+
+	Copyright (c) 2006 Simon Brown                          si@sjbrown.co.uk
+
+	Permission is hereby granted, free of charge, to any person obtaining
+	a copy of this software and associated documentation files (the 
+	"Software"), to	deal in the Software without restriction, including
+	without limitation the rights to use, copy, modify, merge, publish,
+	distribute, sublicense, and/or sell copies of the Software, and to 
+	permit persons to whom the Software is furnished to do so, subject to 
+	the following conditions:
+
+	The above copyright notice and this permission notice shall be included
+	in all copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+	OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+	IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 
+	CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 
+	TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 
+	SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+	
+   -------------------------------------------------------------------------- */
+   
+#include <squish.h>
+#include "colourset.h"
+#include "maths.h"
+#include "rangefit.h"
+#include "clusterfit.h"
+#include "colourblock.h"
+#include "alpha.h"
+#include "singlecolourfit.h"
+
+namespace squish {
+
+static int FixFlags( int flags )
+{
+	// grab the flag bits
+	int method = flags & ( kDxt1 | kDxt3 | kDxt5 );
+	int fit = flags & ( kColourIterativeClusterFit | kColourClusterFit | kColourRangeFit );
+	int metric = flags & ( kColourMetricPerceptual | kColourMetricUniform );
+	int extra = flags & kWeightColourByAlpha;
+	
+	// set defaults
+	if( method != kDxt3 && method != kDxt5 )
+		method = kDxt1;
+	if( fit != kColourRangeFit )
+		fit = kColourClusterFit;
+	if( metric != kColourMetricUniform )
+		metric = kColourMetricPerceptual;
+		
+	// done
+	return method | fit | metric | extra;
+}
+
+void Compress( u8 const* rgba, void* block, int flags )
+{
+	// compress with full mask
+	CompressMasked( rgba, 0xffff, block, flags );
+}
+
+void CompressMasked( u8 const* rgba, int mask, void* block, int flags )
+{
+	// fix any bad flags
+	flags = FixFlags( flags );
+
+	// get the block locations
+	void* colourBlock = block;
+	void* alphaBock = block;
+	if( ( flags & ( kDxt3 | kDxt5 ) ) != 0 )
+		colourBlock = reinterpret_cast< u8* >( block ) + 8;
+
+	// create the minimal point set
+	ColourSet colours( rgba, mask, flags );
+	
+	// check the compression type and compress colour
+	if( colours.GetCount() == 1 )
+	{
+		// always do a single colour fit
+		SingleColourFit fit( &colours, flags );
+		fit.Compress( colourBlock );
+	}
+	else if( ( flags & kColourRangeFit ) != 0 || colours.GetCount() == 0 )
+	{
+		// do a range fit
+		RangeFit fit( &colours, flags );
+		fit.Compress( colourBlock );
+	}
+	else
+	{
+		// default to a cluster fit (could be iterative or not)
+		ClusterFit fit( &colours, flags );
+		fit.Compress( colourBlock );
+	}
+	
+	// compress alpha separately if necessary
+	if( ( flags & kDxt3 ) != 0 )
+		CompressAlphaDxt3( rgba, mask, alphaBock );
+	else if( ( flags & kDxt5 ) != 0 )
+		CompressAlphaDxt5( rgba, mask, alphaBock );
+}
+
+void Decompress( u8* rgba, void const* block, int flags )
+{
+	// fix any bad flags
+	flags = FixFlags( flags );
+
+	// get the block locations
+	void const* colourBlock = block;
+	void const* alphaBock = block;
+	if( ( flags & ( kDxt3 | kDxt5 ) ) != 0 )
+		colourBlock = reinterpret_cast< u8 const* >( block ) + 8;
+
+	// decompress colour
+	DecompressColour( rgba, colourBlock, ( flags & kDxt1 ) != 0 );
+
+	// decompress alpha separately if necessary
+	if( ( flags & kDxt3 ) != 0 )
+		DecompressAlphaDxt3( rgba, alphaBock );
+	else if( ( flags & kDxt5 ) != 0 )
+		DecompressAlphaDxt5( rgba, alphaBock );
+}
+
+int GetStorageRequirements( int width, int height, int flags )
+{
+	// fix any bad flags
+	flags = FixFlags( flags );
+	
+	// compute the storage requirements
+	int blockcount = ( ( width + 3 )/4 ) * ( ( height + 3 )/4 );
+	int blocksize = ( ( flags & kDxt1 ) != 0 ) ? 8 : 16;
+	return blockcount*blocksize;	
+}
+
+void CompressImage( u8 const* rgba, int width, int height, void* blocks, int flags )
+{
+	// fix any bad flags
+	flags = FixFlags( flags );
+
+	// initialise the block output
+	u8* targetBlock = reinterpret_cast< u8* >( blocks );
+	int bytesPerBlock = ( ( flags & kDxt1 ) != 0 ) ? 8 : 16;
+
+	// loop over blocks
+	for( int y = 0; y < height; y += 4 )
+	{
+		for( int x = 0; x < width; x += 4 )
+		{
+			// build the 4x4 block of pixels
+			u8 sourceRgba[16*4];
+			u8* targetPixel = sourceRgba;
+			int mask = 0;
+			for( int py = 0; py < 4; ++py )
+			{
+				for( int px = 0; px < 4; ++px )
+				{
+					// get the source pixel in the image
+					int sx = x + px;
+					int sy = y + py;
+					
+					// enable if we're in the image
+					if( sx < width && sy < height )
+					{
+						// copy the rgba value
+						u8 const* sourcePixel = rgba + 4*( width*sy + sx );
+						for( int i = 0; i < 4; ++i )
+							*targetPixel++ = *sourcePixel++;
+							
+						// enable this pixel
+						mask |= ( 1 << ( 4*py + px ) );
+					}
+					else
+					{
+						// skip this pixel as its outside the image
+						targetPixel += 4;
+					}
+				}
+			}
+			
+			// compress it into the output
+			CompressMasked( sourceRgba, mask, targetBlock, flags );
+			
+			// advance
+			targetBlock += bytesPerBlock;
+		}
+	}
+}
+
+void DecompressImage( u8* rgba, int width, int height, void const* blocks, int flags )
+{
+	// fix any bad flags
+	flags = FixFlags( flags );
+
+	// initialise the block input
+	u8 const* sourceBlock = reinterpret_cast< u8 const* >( blocks );
+	int bytesPerBlock = ( ( flags & kDxt1 ) != 0 ) ? 8 : 16;
+
+	// loop over blocks
+	for( int y = 0; y < height; y += 4 )
+	{
+		for( int x = 0; x < width; x += 4 )
+		{
+			// decompress the block
+			u8 targetRgba[4*16];
+			Decompress( targetRgba, sourceBlock, flags );
+			
+			// write the decompressed pixels to the correct image locations
+			u8 const* sourcePixel = targetRgba;
+			for( int py = 0; py < 4; ++py )
+			{
+				for( int px = 0; px < 4; ++px )
+				{
+					// get the target location
+					int sx = x + px;
+					int sy = y + py;
+					if( sx < width && sy < height )
+					{
+						u8* targetPixel = rgba + 4*( width*sy + sx );
+						
+						// copy the rgba value
+						for( int i = 0; i < 4; ++i )
+							*targetPixel++ = *sourcePixel++;
+					}
+					else
+					{
+						// skip this pixel as its outside the image
+						sourcePixel += 4;
+					}
+				}
+			}
+			
+			// advance
+			sourceBlock += bytesPerBlock;
+		}
+	}
+}
+
+} // namespace squish