124 lines
3.0 KiB
C
124 lines
3.0 KiB
C
/*
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Jonathan Dummer
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2007-07-31-10.32
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simple DXT compression / decompression code
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public domain
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*/
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#ifndef HEADER_IMAGE_DXT
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#define HEADER_IMAGE_DXT
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/**
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Converts an image from an array of unsigned chars (RGB or RGBA) to
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DXT1 or DXT5, then saves the converted image to disk.
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\return 0 if failed, otherwise returns 1
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**/
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int
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save_image_as_DDS
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(
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const char *filename,
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int width, int height, int channels,
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const unsigned char *const data
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);
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/**
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take an image and convert it to DXT1 (no alpha)
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**/
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unsigned char*
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convert_image_to_DXT1
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(
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const unsigned char *const uncompressed,
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int width, int height, int channels,
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int *out_size
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);
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/**
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take an image and convert it to DXT5 (with alpha)
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**/
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unsigned char*
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convert_image_to_DXT5
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(
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const unsigned char *const uncompressed,
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int width, int height, int channels,
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int *out_size
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);
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/** A bunch of DirectDraw Surface structures and flags **/
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typedef struct
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{
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unsigned int dwMagic;
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unsigned int dwSize;
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unsigned int dwFlags;
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unsigned int dwHeight;
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unsigned int dwWidth;
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unsigned int dwPitchOrLinearSize;
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unsigned int dwDepth;
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unsigned int dwMipMapCount;
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unsigned int dwReserved1[ 11 ];
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/* DDPIXELFORMAT */
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struct
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{
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unsigned int dwSize;
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unsigned int dwFlags;
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unsigned int dwFourCC;
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unsigned int dwRGBBitCount;
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unsigned int dwRBitMask;
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unsigned int dwGBitMask;
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unsigned int dwBBitMask;
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unsigned int dwAlphaBitMask;
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}
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sPixelFormat;
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/* DDCAPS2 */
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struct
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{
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unsigned int dwCaps1;
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unsigned int dwCaps2;
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unsigned int dwDDSX;
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unsigned int dwReserved;
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}
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sCaps;
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unsigned int dwReserved2;
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}
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DDS_header ;
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/* the following constants were copied directly off the MSDN website */
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/* The dwFlags member of the original DDSURFACEDESC2 structure
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can be set to one or more of the following values. */
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#define DDSD_CAPS 0x00000001
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#define DDSD_HEIGHT 0x00000002
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#define DDSD_WIDTH 0x00000004
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#define DDSD_PITCH 0x00000008
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#define DDSD_PIXELFORMAT 0x00001000
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#define DDSD_MIPMAPCOUNT 0x00020000
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#define DDSD_LINEARSIZE 0x00080000
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#define DDSD_DEPTH 0x00800000
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/* DirectDraw Pixel Format */
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#define DDPF_ALPHAPIXELS 0x00000001
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#define DDPF_FOURCC 0x00000004
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#define DDPF_RGB 0x00000040
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/* The dwCaps1 member of the DDSCAPS2 structure can be
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set to one or more of the following values. */
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#define DDSCAPS_COMPLEX 0x00000008
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#define DDSCAPS_TEXTURE 0x00001000
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#define DDSCAPS_MIPMAP 0x00400000
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/* The dwCaps2 member of the DDSCAPS2 structure can be
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set to one or more of the following values. */
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#define DDSCAPS2_CUBEMAP 0x00000200
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#define DDSCAPS2_CUBEMAP_POSITIVEX 0x00000400
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#define DDSCAPS2_CUBEMAP_NEGATIVEX 0x00000800
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#define DDSCAPS2_CUBEMAP_POSITIVEY 0x00001000
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#define DDSCAPS2_CUBEMAP_NEGATIVEY 0x00002000
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#define DDSCAPS2_CUBEMAP_POSITIVEZ 0x00004000
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#define DDSCAPS2_CUBEMAP_NEGATIVEZ 0x00008000
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#define DDSCAPS2_VOLUME 0x00200000
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#endif /* HEADER_IMAGE_DXT */
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