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diff --git a/src/parsec/img_supp.cpp b/src/parsec/img_supp.cpp
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+/*
+ * PARSEC - Image/Texture Helper Functions
+ *
+ * $Author: uberlinuxguy $ - $Date: 2004/09/26 03:43:42 $
+ *
+ * Orginally written by:
+ *   Copyright (c) Markus Hadwiger     <msh@parsec.org>   1999-2001
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */ 
+
+// C library
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+// compilation flags/debug support
+#include "config.h"
+#include "debug.h"
+
+// general definitions
+#include "general.h"
+#include "objstruc.h"
+
+// global externals
+#include "globals.h"
+
+// local module header
+#include "img_supp.h"
+
+
+
+// convert numerical aspect ratio to texgeo_aspect spec (glide-style) ---------
+//
+static dword tex_aspect_to_texgeo_gr[] = {
+
+	0,
+	TEXGEO_ASPECT_GR_1x1,
+	TEXGEO_ASPECT_GR_2x1,
+	0,
+	TEXGEO_ASPECT_GR_4x1,
+	0,
+	0,
+	0,
+	TEXGEO_ASPECT_GR_8x1,
+
+	0,
+	TEXGEO_ASPECT_GR_1x1,
+	TEXGEO_ASPECT_GR_1x2,
+	0,
+	TEXGEO_ASPECT_GR_1x4,
+	0,
+	0,
+	0,
+	TEXGEO_ASPECT_GR_1x8,
+};
+
+
+// determine aspect ratio code for texture coordinates ------------------------
+//
+dword IMG_DetermineTexGeoAspect( dword width, dword height )
+{
+	ASSERT( ( width > 0 ) && ( height > 0 ) );
+	ASSERT( ( width & ( width - 1 ) ) == 0 );
+	ASSERT( ( height & ( height - 1 ) ) == 0 );
+
+	if ( width >= height ) {
+		dword aspect = width / height;
+		if ( aspect > 8 )
+			PANIC( 0 );
+		return tex_aspect_to_texgeo_gr[ aspect ];
+	} else {
+		dword aspect = height / width;
+		if ( aspect > 8 )
+			PANIC( 0 );
+		return tex_aspect_to_texgeo_gr[ aspect + 9 ];
+	}
+}
+
+
+// mapping tables for general aspect ratio codes up to 1024 -------------------
+//
+static dword tex_aspect_to_texgeo_horizontal[] = {
+
+	0x04000001, TEXGEO_ASPECT_1024x1,
+	0x02000001, TEXGEO_ASPECT_512x1,
+	0x01000001, TEXGEO_ASPECT_256x1,
+	0x00800001, TEXGEO_ASPECT_128x1,
+	0x00400001, TEXGEO_ASPECT_64x1,
+	0x00200001, TEXGEO_ASPECT_32x1,
+	0x00100001, TEXGEO_ASPECT_16x1,
+	0x00080001, TEXGEO_ASPECT_8x1,
+	0x00040001, TEXGEO_ASPECT_4x1,
+	0x00020001, TEXGEO_ASPECT_2x1,
+	0x00010001, TEXGEO_ASPECT_1x1,
+};
+
+static dword tex_aspect_to_texgeo_vertical[] = {
+
+	0x00010002, TEXGEO_ASPECT_1x2,
+	0x00010004, TEXGEO_ASPECT_1x4,
+	0x00010008, TEXGEO_ASPECT_1x8,
+	0x00010010, TEXGEO_ASPECT_1x16,
+	0x00010020, TEXGEO_ASPECT_1x32,
+	0x00010040, TEXGEO_ASPECT_1x64,
+	0x00010080, TEXGEO_ASPECT_1x128,
+	0x00010100, TEXGEO_ASPECT_1x256,
+	0x00010200, TEXGEO_ASPECT_1x512,
+	0x00010400, TEXGEO_ASPECT_1x1024,
+};
+
+
+// determine (extended) aspect ratio code for texture coordinates -------------
+//
+int IMG_DetermineTexGeoAspectExt( dword width, dword height )
+{
+	ASSERT( ( width > 0 ) && ( height > 0 ) );
+	ASSERT( ( width & ( width - 1 ) ) == 0 );
+	ASSERT( ( height & ( height - 1 ) ) == 0 );
+
+	int asp;
+	unsigned int aindx;
+
+	if ( width > height ) {
+		asp   = width / height;
+		aindx = ( asp << 16 ) | 0x0001;
+	} else {
+		asp = height / width;
+		aindx = ( 0x0001 << 16 ) | asp;
+	}
+
+	// 1024 at most
+	if ( asp > 1024 ) {
+		return -1;
+	}
+
+	int aspect = -1;
+
+	if ( ( aindx & 0xffff ) == 0x0001 ) {
+		int atlen = CALC_NUM_ARRAY_ENTRIES( tex_aspect_to_texgeo_horizontal );
+		for ( int ati = 0; ati < atlen; ati += 2 ) {
+			if ( tex_aspect_to_texgeo_horizontal[ ati ] == aindx ) {
+				aspect = tex_aspect_to_texgeo_horizontal[ ati + 1 ];
+				break;
+			}
+		}
+	} else {
+		int atlen = CALC_NUM_ARRAY_ENTRIES( tex_aspect_to_texgeo_vertical );
+		for ( int ati = 0; ati < atlen; ati += 2 ) {
+			if ( tex_aspect_to_texgeo_vertical[ ati ] == aindx ) {
+				aspect = tex_aspect_to_texgeo_vertical[ ati + 1 ];
+				break;
+			}
+		}
+	}
+
+	return aspect;
+}
+
+
+// determine scale code for texture coordinates -------------------------------
+//
+dword IMG_DetermineTexGeoScale( dword maxside )
+{
+	ASSERT( ( maxside > 0 ) && ( maxside <= 1024 ) );
+	ASSERT( ( maxside & ( maxside - 1 ) ) == 0 );
+
+	//NOTE:
+	// texture coordinate scale factors take care of the mapping from texture
+	// coordinates as stored in an object to native api coordinates. object
+	// texture coordinates are stored unnormalized, i.e., they are actual
+	// absolute coordinates where [0, length-1] covers the texture once.
+	// in glide, the larger side of a texture always has to be scaled to 256.
+	// the smaller side has to be scaled using the same scale factor, thus
+	// preserving the aspect ratio (which is supplied to the api).
+	// in opengl, both sides need to be scaled to 1.0, i.e., the aspect ratio
+	// is not preserved in the coordinates themselves.
+	// in order to derive a scale factor for a texture that can be used by all
+	// renderers, the factor determined here scales the larger side to 256 if
+	// it is smaller or equal to 256 (small textures). larger textures simply
+	// store the power of two of the largest side (not supported by glide).
+
+	// default: take as is
+	dword scalecode = TEXGEO_SCALE_1;
+
+	if ( maxside < 256 ) {
+
+		// glide-style scale factor (1..256)
+		scalecode = ( ( 256 / maxside ) << TEXGEO_SCALESHIFT ) & TEXGEO_SCALEMASK;
+
+		// glide-style scale factor as power of two (0..8)
+		dword sl2 = 0;
+		for ( dword sc = TEXGEO_SCALE_1; sc < scalecode; sc <<= 1 )
+			++sl2;
+		ASSERT( sl2 <= 8 );
+		scalecode |= ( sl2 << TEXGEO_SCALE2SHIFT ) & TEXGEO_SCALE2MASK;
+
+	} else if ( maxside > 256 ) {
+
+		// extended scaling is not to 256 anymore, but to 1024
+		// only the power of two version is stored as table index
+		dword sl2 = ( maxside == 1024 ) ? 10 : 9;
+		scalecode = ( sl2 << TEXGEO_SCALE2SHIFT ) & TEXGEO_SCALE2MASK;
+	}
+
+	return scalecode;
+}
+
+
+// determine number of texels in a texture including all mipmap levels --------
+//
+dword IMG_CountMipmapTexels( dword texw, dword texh, dword lodlarge, dword lodsmall )
+{
+	ASSERT( lodlarge >= lodsmall );
+
+	dword numtexels = texw * texh;
+	dword miptexels = numtexels;
+
+	// count additional texels of lower mipmap levels
+	for ( dword lev = lodlarge; lev > lodsmall; lev-- ) {
+
+		//NOTE:
+		// the next lower mipmap level not always has one forth
+		// the texels of its predecessor. it has half the texels
+		// for an aspect ratio != 1 if the shorter side has
+		// already reached length 1.
+
+		ASSERT( ( texw > 1 ) || ( texh > 1 ) );
+
+		if ( texw > 1 ) {
+			texw >>= 1;
+			miptexels >>= 1;
+		}
+		if ( texh > 1 ) {
+			texh >>= 1;
+			miptexels >>= 1;
+		}
+
+		numtexels += miptexels;
+	}
+
+	return numtexels;
+}
+
+
+