757 lines
18 KiB
C
757 lines
18 KiB
C
/* -----------------------------------------------------------------------------
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DDS Library
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Based on code from Nvidia's DDS example:
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http://www.nvidia.com/object/dxtc_decompression_code.html
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Copyright (c) 2003 Randy Reddig
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All rights reserved.
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Redistribution and use in source and binary forms, with or without modification,
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are permitted provided that the following conditions are met:
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Redistributions of source code must retain the above copyright notice, this list
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of conditions and the following disclaimer.
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Redistributions in binary form must reproduce the above copyright notice, this
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list of conditions and the following disclaimer in the documentation and/or
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other materials provided with the distribution.
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Neither the names of the copyright holders nor the names of its contributors may
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be used to endorse or promote products derived from this software without
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specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
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ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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----------------------------------------------------------------------------- */
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/* dependencies */
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#include "ddslib.h"
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#include "globaldefs.h"
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/* endian tomfoolery */
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typedef union
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{
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float f;
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char c[ 4 ];
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}
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floatSwapUnion;
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#if GDEF_ARCH_ENDIAN_BIG
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int DDSBigLong( int src ) { return src; }
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short DDSBigShort( short src ) { return src; }
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float DDSBigFloat( float src ) { return src; }
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int DDSLittleLong( int src ){
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return ( ( src & 0xFF000000 ) >> 24 ) |
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( ( src & 0x00FF0000 ) >> 8 ) |
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( ( src & 0x0000FF00 ) << 8 ) |
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( ( src & 0x000000FF ) << 24 );
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}
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short DDSLittleShort( short src ){
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return ( ( src & 0xFF00 ) >> 8 ) |
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( ( src & 0x00FF ) << 8 );
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}
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float DDSLittleFloat( float src ){
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floatSwapUnion in,out;
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in.f = src;
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out.c[ 0 ] = in.c[ 3 ];
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out.c[ 1 ] = in.c[ 2 ];
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out.c[ 2 ] = in.c[ 1 ];
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out.c[ 3 ] = in.c[ 0 ];
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return out.f;
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}
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#else /*__BIG_ENDIAN__*/
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int DDSLittleLong( int src ) { return src; }
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short DDSLittleShort( short src ) { return src; }
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float DDSLittleFloat( float src ) { return src; }
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int DDSBigLong( int src ){
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return ( ( src & 0xFF000000 ) >> 24 ) |
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( ( src & 0x00FF0000 ) >> 8 ) |
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( ( src & 0x0000FF00 ) << 8 ) |
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( ( src & 0x000000FF ) << 24 );
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}
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short DDSBigShort( short src ){
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return ( ( src & 0xFF00 ) >> 8 ) |
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( ( src & 0x00FF ) << 8 );
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}
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float DDSBigFloat( float src ){
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floatSwapUnion in,out;
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in.f = src;
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out.c[ 0 ] = in.c[ 3 ];
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out.c[ 1 ] = in.c[ 2 ];
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out.c[ 2 ] = in.c[ 1 ];
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out.c[ 3 ] = in.c[ 0 ];
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return out.f;
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}
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#endif /*__BIG_ENDIAN__*/
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/*
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DDSDecodePixelFormat()
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determines which pixel format the dds texture is in
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*/
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static void DDSDecodePixelFormat( ddsBuffer_t *dds, ddsPF_t *pf ){
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unsigned int fourCC;
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/* dummy check */
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if ( dds == NULL || pf == NULL ) {
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return;
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}
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/* extract fourCC */
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fourCC = dds->pixelFormat.fourCC;
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/* test it */
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if ( fourCC == 0 ) {
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*pf = DDS_PF_ARGB8888;
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}
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else if ( fourCC == *( (unsigned int*) "DXT1" ) ) {
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*pf = DDS_PF_DXT1;
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}
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else if ( fourCC == *( (unsigned int*) "DXT2" ) ) {
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*pf = DDS_PF_DXT2;
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}
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else if ( fourCC == *( (unsigned int*) "DXT3" ) ) {
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*pf = DDS_PF_DXT3;
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}
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else if ( fourCC == *( (unsigned int*) "DXT4" ) ) {
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*pf = DDS_PF_DXT4;
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}
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else if ( fourCC == *( (unsigned int*) "DXT5" ) ) {
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*pf = DDS_PF_DXT5;
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}
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else{
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*pf = DDS_PF_UNKNOWN;
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}
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}
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/*
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DDSGetInfo()
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extracts relevant info from a dds texture, returns 0 on success
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*/
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int DDSGetInfo( ddsBuffer_t *dds, int *width, int *height, ddsPF_t *pf ){
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/* dummy test */
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if ( dds == NULL ) {
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return -1;
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}
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/* test dds header */
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if ( *( (int*) dds->magic ) != *( (int*) "DDS " ) ) {
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return -1;
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}
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if ( DDSLittleLong( dds->size ) != 124 ) {
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return -1;
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}
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/* extract width and height */
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if ( width != NULL ) {
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*width = DDSLittleLong( dds->width );
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}
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if ( height != NULL ) {
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*height = DDSLittleLong( dds->height );
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}
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/* get pixel format */
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DDSDecodePixelFormat( dds, pf );
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/* return ok */
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return 0;
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}
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/*
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DDSGetColorBlockColors()
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extracts colors from a dds color block
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*/
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static void DDSGetColorBlockColors( ddsColorBlock_t *block, ddsColor_t colors[ 4 ] ){
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unsigned short word;
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/* color 0 */
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word = DDSLittleShort( block->colors[ 0 ] );
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colors[ 0 ].a = 0xff;
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/* extract rgb bits */
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colors[ 0 ].b = (unsigned char) word;
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colors[ 0 ].b <<= 3;
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colors[ 0 ].b |= ( colors[ 0 ].b >> 5 );
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word >>= 5;
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colors[ 0 ].g = (unsigned char) word;
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colors[ 0 ].g <<= 2;
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colors[ 0 ].g |= ( colors[ 0 ].g >> 5 );
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word >>= 6;
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colors[ 0 ].r = (unsigned char) word;
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colors[ 0 ].r <<= 3;
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colors[ 0 ].r |= ( colors[ 0 ].r >> 5 );
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/* same for color 1 */
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word = DDSLittleShort( block->colors[ 1 ] );
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colors[ 1 ].a = 0xff;
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/* extract rgb bits */
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colors[ 1 ].b = (unsigned char) word;
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colors[ 1 ].b <<= 3;
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colors[ 1 ].b |= ( colors[ 1 ].b >> 5 );
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word >>= 5;
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colors[ 1 ].g = (unsigned char) word;
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colors[ 1 ].g <<= 2;
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colors[ 1 ].g |= ( colors[ 1 ].g >> 5 );
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word >>= 6;
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colors[ 1 ].r = (unsigned char) word;
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colors[ 1 ].r <<= 3;
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colors[ 1 ].r |= ( colors[ 1 ].r >> 5 );
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/* use this for all but the super-freak math method */
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if ( block->colors[ 0 ] > block->colors[ 1 ] ) {
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/* four-color block: derive the other two colors.
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00 = color 0, 01 = color 1, 10 = color 2, 11 = color 3
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these two bit codes correspond to the 2-bit fields
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stored in the 64-bit block. */
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word = ( (unsigned short) colors[ 0 ].r * 2 + (unsigned short) colors[ 1 ].r ) / 3;
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/* no +1 for rounding */
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/* as bits have been shifted to 888 */
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colors[ 2 ].r = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].g * 2 + (unsigned short) colors[ 1 ].g ) / 3;
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colors[ 2 ].g = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].b * 2 + (unsigned short) colors[ 1 ].b ) / 3;
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colors[ 2 ].b = (unsigned char) word;
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colors[ 2 ].a = 0xff;
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word = ( (unsigned short) colors[ 0 ].r + (unsigned short) colors[ 1 ].r * 2 ) / 3;
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colors[ 3 ].r = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].g + (unsigned short) colors[ 1 ].g * 2 ) / 3;
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colors[ 3 ].g = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].b + (unsigned short) colors[ 1 ].b * 2 ) / 3;
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colors[ 3 ].b = (unsigned char) word;
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colors[ 3 ].a = 0xff;
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}
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else
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{
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/* three-color block: derive the other color.
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00 = color 0, 01 = color 1, 10 = color 2,
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11 = transparent.
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These two bit codes correspond to the 2-bit fields
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stored in the 64-bit block */
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word = ( (unsigned short) colors[ 0 ].r + (unsigned short) colors[ 1 ].r ) / 2;
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colors[ 2 ].r = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].g + (unsigned short) colors[ 1 ].g ) / 2;
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colors[ 2 ].g = (unsigned char) word;
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word = ( (unsigned short) colors[ 0 ].b + (unsigned short) colors[ 1 ].b ) / 2;
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colors[ 2 ].b = (unsigned char) word;
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colors[ 2 ].a = 0xff;
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/* random color to indicate alpha */
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colors[ 3 ].r = 0x00;
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colors[ 3 ].g = 0xff;
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colors[ 3 ].b = 0xff;
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colors[ 3 ].a = 0x00;
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}
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}
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/*
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DDSDecodeColorBlock()
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decodes a dds color block
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fixme: make endian-safe
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*/
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static void DDSDecodeColorBlock( unsigned int *pixel, ddsColorBlock_t *block, int width, unsigned int colors[ 4 ] ){
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int r, n;
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unsigned int bits;
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unsigned int masks[] = { 3, 12, 3 << 4, 3 << 6 }; /* bit masks = 00000011, 00001100, 00110000, 11000000 */
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int shift[] = { 0, 2, 4, 6 };
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/* r steps through lines in y */
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for ( r = 0; r < 4; r++, pixel += ( width - 4 ) ) /* no width * 4 as unsigned int ptr inc will * 4 */
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{
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/* width * 4 bytes per pixel per line, each j dxtc row is 4 lines of pixels */
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/* n steps through pixels */
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for ( n = 0; n < 4; n++ )
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{
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bits = block->row[ r ] & masks[ n ];
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bits >>= shift[ n ];
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switch ( bits )
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{
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case 0:
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*pixel = colors[ 0 ];
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pixel++;
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break;
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case 1:
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*pixel = colors[ 1 ];
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pixel++;
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break;
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case 2:
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*pixel = colors[ 2 ];
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pixel++;
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break;
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case 3:
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*pixel = colors[ 3 ];
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pixel++;
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break;
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default:
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/* invalid */
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pixel++;
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break;
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}
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}
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}
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}
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/*
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DDSDecodeAlphaExplicit()
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decodes a dds explicit alpha block
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*/
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static void DDSDecodeAlphaExplicit( unsigned int *pixel, ddsAlphaBlockExplicit_t *alphaBlock, int width, unsigned int alphaZero ){
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int row, pix;
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unsigned short word;
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ddsColor_t color;
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/* clear color */
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color.r = 0;
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color.g = 0;
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color.b = 0;
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/* walk rows */
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for ( row = 0; row < 4; row++, pixel += ( width - 4 ) )
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{
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word = DDSLittleShort( alphaBlock->row[ row ] );
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/* walk pixels */
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for ( pix = 0; pix < 4; pix++ )
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{
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/* zero the alpha bits of image pixel */
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*pixel &= alphaZero;
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color.a = word & 0x000F;
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color.a = color.a | ( color.a << 4 );
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*pixel |= *( (unsigned int*) &color );
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word >>= 4; /* move next bits to lowest 4 */
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pixel++; /* move to next pixel in the row */
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}
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}
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}
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/*
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DDSDecodeAlpha3BitLinear()
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decodes interpolated alpha block
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*/
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static void DDSDecodeAlpha3BitLinear( unsigned int *pixel, ddsAlphaBlock3BitLinear_t *alphaBlock, int width, unsigned int alphaZero ){
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int row, pix;
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unsigned int stuff;
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unsigned char bits[ 4 ][ 4 ];
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unsigned short alphas[ 8 ];
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ddsColor_t aColors[ 4 ][ 4 ];
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/* get initial alphas */
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alphas[ 0 ] = alphaBlock->alpha0;
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alphas[ 1 ] = alphaBlock->alpha1;
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/* 8-alpha block */
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if ( alphas[ 0 ] > alphas[ 1 ] ) {
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/* 000 = alpha_0, 001 = alpha_1, others are interpolated */
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alphas[ 2 ] = ( 6 * alphas[ 0 ] + alphas[ 1 ] ) / 7; /* bit code 010 */
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alphas[ 3 ] = ( 5 * alphas[ 0 ] + 2 * alphas[ 1 ] ) / 7; /* bit code 011 */
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alphas[ 4 ] = ( 4 * alphas[ 0 ] + 3 * alphas[ 1 ] ) / 7; /* bit code 100 */
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alphas[ 5 ] = ( 3 * alphas[ 0 ] + 4 * alphas[ 1 ] ) / 7; /* bit code 101 */
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alphas[ 6 ] = ( 2 * alphas[ 0 ] + 5 * alphas[ 1 ] ) / 7; /* bit code 110 */
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alphas[ 7 ] = ( alphas[ 0 ] + 6 * alphas[ 1 ] ) / 7; /* bit code 111 */
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}
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/* 6-alpha block */
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else
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{
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/* 000 = alpha_0, 001 = alpha_1, others are interpolated */
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alphas[ 2 ] = ( 4 * alphas[ 0 ] + alphas[ 1 ] ) / 5; /* bit code 010 */
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alphas[ 3 ] = ( 3 * alphas[ 0 ] + 2 * alphas[ 1 ] ) / 5; /* bit code 011 */
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alphas[ 4 ] = ( 2 * alphas[ 0 ] + 3 * alphas[ 1 ] ) / 5; /* bit code 100 */
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alphas[ 5 ] = ( alphas[ 0 ] + 4 * alphas[ 1 ] ) / 5; /* bit code 101 */
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alphas[ 6 ] = 0; /* bit code 110 */
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alphas[ 7 ] = 255; /* bit code 111 */
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}
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/* decode 3-bit fields into array of 16 bytes with same value */
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/* first two rows of 4 pixels each */
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stuff = *( (unsigned int*) &( alphaBlock->stuff[ 0 ] ) );
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bits[ 0 ][ 0 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 0 ][ 1 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 0 ][ 2 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 0 ][ 3 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 1 ][ 0 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 1 ][ 1 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 1 ][ 2 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 1 ][ 3 ] = (unsigned char) ( stuff & 0x00000007 );
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/* last two rows */
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stuff = *( (unsigned int*) &( alphaBlock->stuff[ 3 ] ) ); /* last 3 bytes */
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bits[ 2 ][ 0 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 2 ][ 1 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 2 ][ 2 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 2 ][ 3 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 3 ][ 0 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 3 ][ 1 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 3 ][ 2 ] = (unsigned char) ( stuff & 0x00000007 );
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stuff >>= 3;
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bits[ 3 ][ 3 ] = (unsigned char) ( stuff & 0x00000007 );
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/* decode the codes into alpha values */
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for ( row = 0; row < 4; row++ )
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{
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for ( pix = 0; pix < 4; pix++ )
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{
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aColors[ row ][ pix ].r = 0;
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aColors[ row ][ pix ].g = 0;
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aColors[ row ][ pix ].b = 0;
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aColors[ row ][ pix ].a = (unsigned char) alphas[ bits[ row ][ pix ] ];
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}
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}
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/* write out alpha values to the image bits */
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for ( row = 0; row < 4; row++, pixel += width - 4 )
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{
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for ( pix = 0; pix < 4; pix++ )
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{
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/* zero the alpha bits of image pixel */
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*pixel &= alphaZero;
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/* or the bits into the prev. nulled alpha */
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*pixel |= *( (unsigned int*) &( aColors[ row ][ pix ] ) );
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pixel++;
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}
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}
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}
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/*
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DDSDecompressDXT1()
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decompresses a dxt1 format texture
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*/
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static int DDSDecompressDXT1( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
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int x, y, xBlocks, yBlocks;
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unsigned int *pixel;
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ddsColorBlock_t *block;
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ddsColor_t colors[ 4 ];
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/* setup */
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xBlocks = width / 4;
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yBlocks = height / 4;
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/* walk y */
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for ( y = 0; y < yBlocks; y++ )
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{
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/* 8 bytes per block */
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block = (ddsColorBlock_t*) ( (char *) dds->data + y * xBlocks * 8 );
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/* walk x */
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for ( x = 0; x < xBlocks; x++, block++ )
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{
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DDSGetColorBlockColors( block, colors );
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pixel = (unsigned int*) ( pixels + x * 16 + ( y * 4 ) * width * 4 );
|
|
DDSDecodeColorBlock( pixel, block, width, (unsigned int*) colors );
|
|
}
|
|
}
|
|
|
|
/* return ok */
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompressDXT3()
|
|
decompresses a dxt3 format texture
|
|
*/
|
|
|
|
static int DDSDecompressDXT3( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
|
|
int x, y, xBlocks, yBlocks;
|
|
unsigned int *pixel, alphaZero;
|
|
ddsColorBlock_t *block;
|
|
ddsAlphaBlockExplicit_t *alphaBlock;
|
|
ddsColor_t colors[ 4 ];
|
|
|
|
|
|
/* setup */
|
|
xBlocks = width / 4;
|
|
yBlocks = height / 4;
|
|
|
|
/* create zero alpha */
|
|
colors[ 0 ].a = 0;
|
|
colors[ 0 ].r = 0xFF;
|
|
colors[ 0 ].g = 0xFF;
|
|
colors[ 0 ].b = 0xFF;
|
|
alphaZero = *( (unsigned int*) &colors[ 0 ] );
|
|
|
|
/* walk y */
|
|
for ( y = 0; y < yBlocks; y++ )
|
|
{
|
|
/* 8 bytes per block, 1 block for alpha, 1 block for color */
|
|
block = (ddsColorBlock_t*) ( (char *) dds->data + y * xBlocks * 16 );
|
|
|
|
/* walk x */
|
|
for ( x = 0; x < xBlocks; x++, block++ )
|
|
{
|
|
/* get alpha block */
|
|
alphaBlock = (ddsAlphaBlockExplicit_t*) block;
|
|
|
|
/* get color block */
|
|
block++;
|
|
DDSGetColorBlockColors( block, colors );
|
|
|
|
/* decode color block */
|
|
pixel = (unsigned int*) ( pixels + x * 16 + ( y * 4 ) * width * 4 );
|
|
DDSDecodeColorBlock( pixel, block, width, (unsigned int*) colors );
|
|
|
|
/* overwrite alpha bits with alpha block */
|
|
DDSDecodeAlphaExplicit( pixel, alphaBlock, width, alphaZero );
|
|
}
|
|
}
|
|
|
|
/* return ok */
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompressDXT5()
|
|
decompresses a dxt5 format texture
|
|
*/
|
|
|
|
static int DDSDecompressDXT5( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
|
|
int x, y, xBlocks, yBlocks;
|
|
unsigned int *pixel, alphaZero;
|
|
ddsColorBlock_t *block;
|
|
ddsAlphaBlock3BitLinear_t *alphaBlock;
|
|
ddsColor_t colors[ 4 ];
|
|
|
|
|
|
/* setup */
|
|
xBlocks = width / 4;
|
|
yBlocks = height / 4;
|
|
|
|
/* create zero alpha */
|
|
colors[ 0 ].a = 0;
|
|
colors[ 0 ].r = 0xFF;
|
|
colors[ 0 ].g = 0xFF;
|
|
colors[ 0 ].b = 0xFF;
|
|
alphaZero = *( (unsigned int*) &colors[ 0 ] );
|
|
|
|
/* walk y */
|
|
for ( y = 0; y < yBlocks; y++ )
|
|
{
|
|
/* 8 bytes per block, 1 block for alpha, 1 block for color */
|
|
block = (ddsColorBlock_t*) ( (char *) dds->data + y * xBlocks * 16 );
|
|
|
|
/* walk x */
|
|
for ( x = 0; x < xBlocks; x++, block++ )
|
|
{
|
|
/* get alpha block */
|
|
alphaBlock = (ddsAlphaBlock3BitLinear_t*) block;
|
|
|
|
/* get color block */
|
|
block++;
|
|
DDSGetColorBlockColors( block, colors );
|
|
|
|
/* decode color block */
|
|
pixel = (unsigned int*) ( pixels + x * 16 + ( y * 4 ) * width * 4 );
|
|
DDSDecodeColorBlock( pixel, block, width, (unsigned int*) colors );
|
|
|
|
/* overwrite alpha bits with alpha block */
|
|
DDSDecodeAlpha3BitLinear( pixel, alphaBlock, width, alphaZero );
|
|
}
|
|
}
|
|
|
|
/* return ok */
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompressDXT2()
|
|
decompresses a dxt2 format texture (fixme: un-premultiply alpha)
|
|
*/
|
|
|
|
static int DDSDecompressDXT2( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
|
|
int r;
|
|
|
|
|
|
/* decompress dxt3 first */
|
|
r = DDSDecompressDXT3( dds, width, height, pixels );
|
|
|
|
/* return to sender */
|
|
return r;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompressDXT4()
|
|
decompresses a dxt4 format texture (fixme: un-premultiply alpha)
|
|
*/
|
|
|
|
static int DDSDecompressDXT4( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
|
|
int r;
|
|
|
|
|
|
/* decompress dxt5 first */
|
|
r = DDSDecompressDXT5( dds, width, height, pixels );
|
|
|
|
/* return to sender */
|
|
return r;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompressARGB8888()
|
|
decompresses an argb 8888 format texture
|
|
*/
|
|
|
|
static int DDSDecompressARGB8888( ddsBuffer_t *dds, int width, int height, unsigned char *pixels ){
|
|
int x, y;
|
|
unsigned char *in, *out;
|
|
|
|
|
|
/* setup */
|
|
in = dds->data;
|
|
out = pixels;
|
|
|
|
/* walk y */
|
|
for ( y = 0; y < height; y++ )
|
|
{
|
|
/* walk x */
|
|
for ( x = 0; x < width; x++ )
|
|
{
|
|
*out++ = *in++;
|
|
*out++ = *in++;
|
|
*out++ = *in++;
|
|
*out++ = *in++;
|
|
}
|
|
}
|
|
|
|
/* return ok */
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
DDSDecompress()
|
|
decompresses a dds texture into an rgba image buffer, returns 0 on success
|
|
*/
|
|
|
|
int DDSDecompress( ddsBuffer_t *dds, unsigned char *pixels ){
|
|
int width, height, r;
|
|
ddsPF_t pf;
|
|
|
|
|
|
/* get dds info */
|
|
r = DDSGetInfo( dds, &width, &height, &pf );
|
|
if ( r ) {
|
|
return r;
|
|
}
|
|
|
|
/* decompress */
|
|
switch ( pf )
|
|
{
|
|
case DDS_PF_ARGB8888:
|
|
/* fixme: support other [a]rgb formats */
|
|
r = DDSDecompressARGB8888( dds, width, height, pixels );
|
|
break;
|
|
|
|
case DDS_PF_DXT1:
|
|
r = DDSDecompressDXT1( dds, width, height, pixels );
|
|
break;
|
|
|
|
case DDS_PF_DXT2:
|
|
r = DDSDecompressDXT2( dds, width, height, pixels );
|
|
break;
|
|
|
|
case DDS_PF_DXT3:
|
|
r = DDSDecompressDXT3( dds, width, height, pixels );
|
|
break;
|
|
|
|
case DDS_PF_DXT4:
|
|
r = DDSDecompressDXT4( dds, width, height, pixels );
|
|
break;
|
|
|
|
case DDS_PF_DXT5:
|
|
r = DDSDecompressDXT5( dds, width, height, pixels );
|
|
break;
|
|
|
|
default:
|
|
case DDS_PF_UNKNOWN:
|
|
memset( pixels, 0xFF, width * height * 4 );
|
|
r = -1;
|
|
break;
|
|
}
|
|
|
|
/* return to sender */
|
|
return r;
|
|
}
|