Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 5131 | clevermous | 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
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| 3 | Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga |
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| 4 | |||
| 5 | This library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Library General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2 of the License, or (at your option) any later version. |
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| 9 | |||
| 10 | This library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Library General Public License for more details. |
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| 14 | |||
| 15 | You should have received a copy of the GNU Library General Public |
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| 16 | License along with this library; if not, write to the Free |
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| 17 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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| 18 | |||
| 19 | Sam Lantinga |
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| 20 | slouken@devolution.com |
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| 21 | */ |
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| 22 | |||
| 23 | |||
| 24 | /* General (mostly internal) pixel/color manipulation routines for SDL */ |
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| 25 | |||
| 26 | #include |
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| 27 | #include |
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| 28 | #include |
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| 29 | |||
| 30 | #include "SDL_error.h" |
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| 31 | #include "SDL_endian.h" |
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| 32 | #include "SDL_video.h" |
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| 33 | #include "SDL_sysvideo.h" |
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| 34 | #include "SDL_blit.h" |
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| 35 | #include "SDL_pixels_c.h" |
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| 36 | #include "SDL_RLEaccel_c.h" |
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| 37 | |||
| 38 | /* Helper functions */ |
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| 39 | /* |
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| 40 | * Allocate a pixel format structure and fill it according to the given info. |
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| 41 | */ |
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| 42 | SDL_PixelFormat *SDL_AllocFormat(int bpp, |
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| 43 | Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) |
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| 44 | { |
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| 45 | SDL_PixelFormat *format; |
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| 46 | Uint32 mask; |
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| 47 | |||
| 48 | /* Allocate an empty pixel format structure */ |
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| 49 | format = malloc(sizeof(*format)); |
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| 50 | if ( format == NULL ) { |
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| 51 | SDL_OutOfMemory(); |
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| 52 | return(NULL); |
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| 53 | } |
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| 54 | memset(format, 0, sizeof(*format)); |
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| 55 | format->alpha = SDL_ALPHA_OPAQUE; |
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| 56 | |||
| 57 | /* Set up the format */ |
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| 58 | format->BitsPerPixel = bpp; |
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| 59 | format->BytesPerPixel = (bpp+7)/8; |
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| 60 | switch (bpp) { |
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| 61 | case 1: |
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| 62 | /* Create the 2 color black-white palette */ |
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| 63 | format->palette = (SDL_Palette *)malloc( |
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| 64 | sizeof(SDL_Palette)); |
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| 65 | if ( format->palette == NULL ) { |
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| 66 | SDL_FreeFormat(format); |
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| 67 | SDL_OutOfMemory(); |
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| 68 | return(NULL); |
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| 69 | } |
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| 70 | (format->palette)->ncolors = 2; |
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| 71 | (format->palette)->colors = (SDL_Color *)malloc( |
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| 72 | (format->palette)->ncolors*sizeof(SDL_Color)); |
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| 73 | if ( (format->palette)->colors == NULL ) { |
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| 74 | SDL_FreeFormat(format); |
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| 75 | SDL_OutOfMemory(); |
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| 76 | return(NULL); |
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| 77 | } |
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| 78 | format->palette->colors[0].r = 0xFF; |
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| 79 | format->palette->colors[0].g = 0xFF; |
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| 80 | format->palette->colors[0].b = 0xFF; |
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| 81 | format->palette->colors[1].r = 0x00; |
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| 82 | format->palette->colors[1].g = 0x00; |
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| 83 | format->palette->colors[1].b = 0x00; |
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| 84 | format->Rloss = 8; |
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| 85 | format->Gloss = 8; |
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| 86 | format->Bloss = 8; |
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| 87 | format->Aloss = 8; |
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| 88 | format->Rshift = 0; |
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| 89 | format->Gshift = 0; |
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| 90 | format->Bshift = 0; |
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| 91 | format->Ashift = 0; |
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| 92 | format->Rmask = 0; |
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| 93 | format->Gmask = 0; |
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| 94 | format->Bmask = 0; |
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| 95 | format->Amask = 0; |
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| 96 | break; |
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| 97 | |||
| 98 | case 4: |
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| 99 | /* Create the 16 color VGA palette */ |
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| 100 | format->palette = (SDL_Palette *)malloc( |
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| 101 | sizeof(SDL_Palette)); |
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| 102 | if ( format->palette == NULL ) { |
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| 103 | SDL_FreeFormat(format); |
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| 104 | SDL_OutOfMemory(); |
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| 105 | return(NULL); |
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| 106 | } |
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| 107 | (format->palette)->ncolors = 16; |
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| 108 | (format->palette)->colors = (SDL_Color *)malloc( |
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| 109 | (format->palette)->ncolors*sizeof(SDL_Color)); |
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| 110 | if ( (format->palette)->colors == NULL ) { |
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| 111 | SDL_FreeFormat(format); |
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| 112 | SDL_OutOfMemory(); |
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| 113 | return(NULL); |
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| 114 | } |
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| 115 | /* Punt for now, will this ever be used? */ |
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| 116 | memset((format->palette)->colors, 0, |
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| 117 | (format->palette)->ncolors*sizeof(SDL_Color)); |
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| 118 | |||
| 119 | /* Palettized formats have no mask info */ |
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| 120 | format->Rloss = 8; |
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| 121 | format->Gloss = 8; |
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| 122 | format->Bloss = 8; |
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| 123 | format->Aloss = 8; |
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| 124 | format->Rshift = 0; |
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| 125 | format->Gshift = 0; |
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| 126 | format->Bshift = 0; |
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| 127 | format->Ashift = 0; |
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| 128 | format->Rmask = 0; |
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| 129 | format->Gmask = 0; |
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| 130 | format->Bmask = 0; |
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| 131 | format->Amask = 0; |
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| 132 | break; |
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| 133 | |||
| 134 | case 8: |
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| 135 | /* Create an empty 256 color palette */ |
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| 136 | format->palette = (SDL_Palette *)malloc( |
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| 137 | sizeof(SDL_Palette)); |
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| 138 | if ( format->palette == NULL ) { |
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| 139 | SDL_FreeFormat(format); |
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| 140 | SDL_OutOfMemory(); |
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| 141 | return(NULL); |
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| 142 | } |
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| 143 | (format->palette)->ncolors = 256; |
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| 144 | (format->palette)->colors = (SDL_Color *)malloc( |
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| 145 | (format->palette)->ncolors*sizeof(SDL_Color)); |
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| 146 | if ( (format->palette)->colors == NULL ) { |
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| 147 | SDL_FreeFormat(format); |
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| 148 | SDL_OutOfMemory(); |
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| 149 | return(NULL); |
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| 150 | } |
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| 151 | memset((format->palette)->colors, 0, |
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| 152 | (format->palette)->ncolors*sizeof(SDL_Color)); |
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| 153 | |||
| 154 | /* Palettized formats have no mask info */ |
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| 155 | format->Rloss = 8; |
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| 156 | format->Gloss = 8; |
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| 157 | format->Bloss = 8; |
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| 158 | format->Aloss = 8; |
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| 159 | format->Rshift = 0; |
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| 160 | format->Gshift = 0; |
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| 161 | format->Bshift = 0; |
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| 162 | format->Ashift = 0; |
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| 163 | format->Rmask = 0; |
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| 164 | format->Gmask = 0; |
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| 165 | format->Bmask = 0; |
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| 166 | format->Amask = 0; |
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| 167 | break; |
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| 168 | |||
| 169 | default: |
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| 170 | /* No palette, just packed pixel info */ |
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| 171 | format->palette = NULL; |
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| 172 | format->Rshift = 0; |
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| 173 | format->Rloss = 8; |
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| 174 | if ( Rmask ) { |
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| 175 | for ( mask = Rmask; !(mask&0x01); mask >>= 1 ) |
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| 176 | ++format->Rshift; |
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| 177 | for ( ; (mask&0x01); mask >>= 1 ) |
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| 178 | --format->Rloss; |
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| 179 | } |
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| 180 | format->Gshift = 0; |
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| 181 | format->Gloss = 8; |
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| 182 | if ( Gmask ) { |
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| 183 | for ( mask = Gmask; !(mask&0x01); mask >>= 1 ) |
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| 184 | ++format->Gshift; |
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| 185 | for ( ; (mask&0x01); mask >>= 1 ) |
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| 186 | --format->Gloss; |
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| 187 | } |
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| 188 | format->Bshift = 0; |
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| 189 | format->Bloss = 8; |
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| 190 | if ( Bmask ) { |
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| 191 | for ( mask = Bmask; !(mask&0x01); mask >>= 1 ) |
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| 192 | ++format->Bshift; |
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| 193 | for ( ; (mask&0x01); mask >>= 1 ) |
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| 194 | --format->Bloss; |
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| 195 | } |
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| 196 | format->Ashift = 0; |
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| 197 | format->Aloss = 8; |
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| 198 | if ( Amask ) { |
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| 199 | for ( mask = Amask; !(mask&0x01); mask >>= 1 ) |
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| 200 | ++format->Ashift; |
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| 201 | for ( ; (mask&0x01); mask >>= 1 ) |
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| 202 | --format->Aloss; |
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| 203 | } |
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| 204 | format->Rmask = Rmask; |
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| 205 | format->Gmask = Gmask; |
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| 206 | format->Bmask = Bmask; |
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| 207 | format->Amask = Amask; |
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| 208 | break; |
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| 209 | } |
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| 210 | /* Calculate some standard bitmasks, if necessary |
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| 211 | * Note: This could conflict with an alpha mask, if given. |
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| 212 | */ |
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| 213 | if ( (bpp > 8) && !format->Rmask && !format->Gmask && !format->Bmask ) { |
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| 214 | /* R-G-B */ |
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| 215 | if ( bpp > 24 ) |
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| 216 | bpp = 24; |
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| 217 | format->Rloss = 8-(bpp/3); |
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| 218 | format->Gloss = 8-(bpp/3)-(bpp%3); |
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| 219 | format->Bloss = 8-(bpp/3); |
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| 220 | format->Rshift = ((bpp/3)+(bpp%3))+(bpp/3); |
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| 221 | format->Gshift = (bpp/3); |
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| 222 | format->Bshift = 0; |
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| 223 | format->Rmask = ((0xFF>>format->Rloss)< |
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| 224 | format->Gmask = ((0xFF>>format->Gloss)< |
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| 225 | format->Bmask = ((0xFF>>format->Bloss)< |
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| 226 | } |
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| 227 | return(format); |
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| 228 | } |
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| 229 | SDL_PixelFormat *SDL_ReallocFormat(SDL_Surface *surface, int bpp, |
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| 230 | Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) |
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| 231 | { |
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| 232 | if ( surface->format ) { |
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| 233 | SDL_FreeFormat(surface->format); |
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| 234 | SDL_FormatChanged(surface); |
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| 235 | } |
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| 236 | surface->format = SDL_AllocFormat(bpp, Rmask, Gmask, Bmask, Amask); |
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| 237 | return surface->format; |
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| 238 | } |
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| 239 | |||
| 240 | /* |
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| 241 | * Change any previous mappings from/to the new surface format |
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| 242 | */ |
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| 243 | void SDL_FormatChanged(SDL_Surface *surface) |
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| 244 | { |
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| 245 | surface->format_version++; |
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| 246 | SDL_InvalidateMap(surface->map); |
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| 247 | } |
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| 248 | /* |
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| 249 | * Free a previously allocated format structure |
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| 250 | */ |
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| 251 | void SDL_FreeFormat(SDL_PixelFormat *format) |
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| 252 | { |
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| 253 | if ( format ) { |
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| 254 | if ( format->palette ) { |
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| 255 | if ( format->palette->colors ) { |
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| 256 | free(format->palette->colors); |
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| 257 | } |
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| 258 | free(format->palette); |
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| 259 | } |
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| 260 | free(format); |
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| 261 | } |
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| 262 | } |
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| 263 | /* |
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| 264 | * Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors |
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| 265 | */ |
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| 266 | void SDL_DitherColors(SDL_Color *colors, int bpp) |
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| 267 | { |
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| 268 | int i; |
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| 269 | if(bpp != 8) |
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| 270 | return; /* only 8bpp supported right now */ |
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| 271 | |||
| 272 | for(i = 0; i < 256; i++) { |
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| 273 | int r, g, b; |
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| 274 | /* map each bit field to the full [0, 255] interval, |
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| 275 | so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */ |
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| 276 | r = i & 0xe0; |
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| 277 | r |= r >> 3 | r >> 6; |
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| 278 | colors[i].r = r; |
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| 279 | g = (i << 3) & 0xe0; |
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| 280 | g |= g >> 3 | g >> 6; |
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| 281 | colors[i].g = g; |
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| 282 | b = i & 0x3; |
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| 283 | b |= b << 2; |
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| 284 | b |= b << 4; |
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| 285 | colors[i].b = b; |
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| 286 | } |
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| 287 | } |
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| 288 | /* |
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| 289 | * Calculate the pad-aligned scanline width of a surface |
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| 290 | */ |
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| 291 | Uint16 SDL_CalculatePitch(SDL_Surface *surface) |
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| 292 | { |
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| 293 | Uint16 pitch; |
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| 294 | |||
| 295 | /* Surface should be 4-byte aligned for speed */ |
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| 296 | pitch = surface->w*surface->format->BytesPerPixel; |
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| 297 | switch (surface->format->BitsPerPixel) { |
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| 298 | case 1: |
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| 299 | pitch = (pitch+7)/8; |
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| 300 | break; |
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| 301 | case 4: |
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| 302 | pitch = (pitch+1)/2; |
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| 303 | break; |
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| 304 | default: |
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| 305 | break; |
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| 306 | } |
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| 307 | pitch = (pitch + 3) & ~3; /* 4-byte aligning */ |
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| 308 | return(pitch); |
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| 309 | } |
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| 310 | /* |
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| 311 | * Match an RGB value to a particular palette index |
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| 312 | */ |
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| 313 | Uint8 SDL_FindColor(SDL_Palette *pal, Uint8 r, Uint8 g, Uint8 b) |
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| 314 | { |
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| 315 | /* Do colorspace distance matching */ |
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| 316 | unsigned int smallest; |
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| 317 | unsigned int distance; |
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| 318 | int rd, gd, bd; |
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| 319 | int i; |
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| 320 | Uint8 pixel=0; |
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| 321 | |||
| 322 | smallest = ~0; |
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| 323 | for ( i=0; i |
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| 324 | rd = pal->colors[i].r - r; |
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| 325 | gd = pal->colors[i].g - g; |
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| 326 | bd = pal->colors[i].b - b; |
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| 327 | distance = (rd*rd)+(gd*gd)+(bd*bd); |
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| 328 | if ( distance < smallest ) { |
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| 329 | pixel = i; |
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| 330 | if ( distance == 0 ) { /* Perfect match! */ |
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| 331 | break; |
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| 332 | } |
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| 333 | smallest = distance; |
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| 334 | } |
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| 335 | } |
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| 336 | return(pixel); |
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| 337 | } |
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| 338 | |||
| 339 | /* Find the opaque pixel value corresponding to an RGB triple */ |
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| 340 | Uint32 SDL_MapRGB(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b) |
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| 341 | { |
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| 342 | if ( format->palette == NULL ) { |
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| 343 | return (r >> format->Rloss) << format->Rshift |
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| 344 | | (g >> format->Gloss) << format->Gshift |
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| 345 | | (b >> format->Bloss) << format->Bshift |
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| 346 | | format->Amask; |
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| 347 | } else { |
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| 348 | return SDL_FindColor(format->palette, r, g, b); |
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| 349 | } |
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| 350 | } |
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| 351 | |||
| 352 | /* Find the pixel value corresponding to an RGBA quadruple */ |
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| 353 | Uint32 SDL_MapRGBA(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b, Uint8 a) |
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| 354 | { |
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| 355 | if ( format->palette == NULL ) { |
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| 356 | return (r >> format->Rloss) << format->Rshift |
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| 357 | | (g >> format->Gloss) << format->Gshift |
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| 358 | | (b >> format->Bloss) << format->Bshift |
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| 359 | | ((a >> format->Aloss) << format->Ashift & format->Amask); |
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| 360 | } else { |
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| 361 | return SDL_FindColor(format->palette, r, g, b); |
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| 362 | } |
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| 363 | } |
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| 364 | |||
| 365 | void SDL_GetRGBA(Uint32 pixel, SDL_PixelFormat *fmt, |
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| 366 | Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a) |
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| 367 | { |
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| 368 | if ( fmt->palette == NULL ) { |
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| 369 | /* |
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| 370 | * This makes sure that the result is mapped to the |
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| 371 | * interval [0..255], and the maximum value for each |
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| 372 | * component is 255. This is important to make sure |
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| 373 | * that white is indeed reported as (255, 255, 255), |
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| 374 | * and that opaque alpha is 255. |
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| 375 | * This only works for RGB bit fields at least 4 bit |
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| 376 | * wide, which is almost always the case. |
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| 377 | */ |
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| 378 | unsigned rv, gv, bv, av; |
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| 379 | rv = (pixel & fmt->Rmask) >> fmt->Rshift; |
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| 380 | *r = (rv << fmt->Rloss) + (rv >> (8 - fmt->Rloss)); |
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| 381 | gv = (pixel & fmt->Gmask) >> fmt->Gshift; |
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| 382 | *g = (gv << fmt->Gloss) + (gv >> (8 - fmt->Gloss)); |
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| 383 | bv = (pixel & fmt->Bmask) >> fmt->Bshift; |
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| 384 | *b = (bv << fmt->Bloss) + (bv >> (8 - fmt->Bloss)); |
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| 385 | if(fmt->Amask) { |
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| 386 | av = (pixel & fmt->Amask) >> fmt->Ashift; |
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| 387 | *a = (av << fmt->Aloss) + (av >> (8 - fmt->Aloss)); |
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| 388 | } else |
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| 389 | *a = SDL_ALPHA_OPAQUE; |
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| 390 | } else { |
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| 391 | *r = fmt->palette->colors[pixel].r; |
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| 392 | *g = fmt->palette->colors[pixel].g; |
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| 393 | *b = fmt->palette->colors[pixel].b; |
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| 394 | *a = SDL_ALPHA_OPAQUE; |
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| 395 | } |
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| 396 | } |
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| 397 | |||
| 398 | void SDL_GetRGB(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r,Uint8 *g,Uint8 *b) |
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| 399 | { |
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| 400 | if ( fmt->palette == NULL ) { |
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| 401 | /* the note for SDL_GetRGBA above applies here too */ |
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| 402 | unsigned rv, gv, bv; |
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| 403 | rv = (pixel & fmt->Rmask) >> fmt->Rshift; |
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| 404 | *r = (rv << fmt->Rloss) + (rv >> (8 - fmt->Rloss)); |
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| 405 | gv = (pixel & fmt->Gmask) >> fmt->Gshift; |
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| 406 | *g = (gv << fmt->Gloss) + (gv >> (8 - fmt->Gloss)); |
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| 407 | bv = (pixel & fmt->Bmask) >> fmt->Bshift; |
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| 408 | *b = (bv << fmt->Bloss) + (bv >> (8 - fmt->Bloss)); |
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| 409 | } else { |
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| 410 | *r = fmt->palette->colors[pixel].r; |
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| 411 | *g = fmt->palette->colors[pixel].g; |
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| 412 | *b = fmt->palette->colors[pixel].b; |
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| 413 | } |
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| 414 | } |
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| 415 | |||
| 416 | /* Apply gamma to a set of colors - this is easy. :) */ |
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| 417 | void SDL_ApplyGamma(Uint16 *gamma, SDL_Color *colors, SDL_Color *output, |
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| 418 | int ncolors) |
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| 419 | { |
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| 420 | int i; |
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| 421 | |||
| 422 | for ( i=0; i |
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| 423 | output[i].r = gamma[0*256 + colors[i].r] >> 8; |
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| 424 | output[i].g = gamma[1*256 + colors[i].g] >> 8; |
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| 425 | output[i].b = gamma[2*256 + colors[i].b] >> 8; |
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| 426 | } |
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| 427 | } |
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| 428 | |||
| 429 | /* Map from Palette to Palette */ |
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| 430 | static Uint8 *Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical) |
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| 431 | { |
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| 432 | Uint8 *map; |
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| 433 | int i; |
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| 434 | |||
| 435 | if ( identical ) { |
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| 436 | if ( src->ncolors <= dst->ncolors ) { |
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| 437 | /* If an identical palette, no need to map */ |
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| 438 | if ( memcmp(src->colors, dst->colors, src->ncolors* |
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| 439 | sizeof(SDL_Color)) == 0 ) { |
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| 440 | *identical = 1; |
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| 441 | return(NULL); |
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| 442 | } |
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| 443 | } |
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| 444 | *identical = 0; |
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| 445 | } |
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| 446 | map = (Uint8 *)malloc(src->ncolors); |
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| 447 | if ( map == NULL ) { |
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| 448 | SDL_OutOfMemory(); |
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| 449 | return(NULL); |
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| 450 | } |
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| 451 | for ( i=0; i |
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| 452 | map[i] = SDL_FindColor(dst, |
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| 453 | src->colors[i].r, src->colors[i].g, src->colors[i].b); |
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| 454 | } |
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| 455 | return(map); |
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| 456 | } |
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| 457 | /* Map from Palette to BitField */ |
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| 458 | static Uint8 *Map1toN(SDL_Palette *src, SDL_PixelFormat *dst) |
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| 459 | { |
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| 460 | Uint8 *map; |
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| 461 | int i; |
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| 462 | int bpp; |
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| 463 | unsigned alpha; |
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| 464 | |||
| 465 | bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel); |
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| 466 | map = (Uint8 *)malloc(src->ncolors*bpp); |
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| 467 | if ( map == NULL ) { |
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| 468 | SDL_OutOfMemory(); |
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| 469 | return(NULL); |
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| 470 | } |
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| 471 | |||
| 472 | alpha = dst->Amask ? SDL_ALPHA_OPAQUE : 0; |
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| 473 | /* We memory copy to the pixel map so the endianness is preserved */ |
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| 474 | for ( i=0; i |
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| 475 | ASSEMBLE_RGBA(&map[i*bpp], dst->BytesPerPixel, dst, |
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| 476 | src->colors[i].r, src->colors[i].g, |
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| 477 | src->colors[i].b, alpha); |
||
| 478 | } |
||
| 479 | return(map); |
||
| 480 | } |
||
| 481 | /* Map from BitField to Dithered-Palette to Palette */ |
||
| 482 | static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical) |
||
| 483 | { |
||
| 484 | /* Generate a 256 color dither palette */ |
||
| 485 | SDL_Palette dithered; |
||
| 486 | SDL_Color colors[256]; |
||
| 487 | |||
| 488 | dithered.ncolors = 256; |
||
| 489 | SDL_DitherColors(colors, 8); |
||
| 490 | dithered.colors = colors; |
||
| 491 | return(Map1to1(&dithered, dst, identical)); |
||
| 492 | } |
||
| 493 | |||
| 494 | SDL_BlitMap *SDL_AllocBlitMap(void) |
||
| 495 | { |
||
| 496 | SDL_BlitMap *map; |
||
| 497 | |||
| 498 | /* Allocate the empty map */ |
||
| 499 | map = (SDL_BlitMap *)malloc(sizeof(*map)); |
||
| 500 | if ( map == NULL ) { |
||
| 501 | SDL_OutOfMemory(); |
||
| 502 | return(NULL); |
||
| 503 | } |
||
| 504 | memset(map, 0, sizeof(*map)); |
||
| 505 | |||
| 506 | /* Allocate the software blit data */ |
||
| 507 | map->sw_data = (struct private_swaccel *)malloc(sizeof(*map->sw_data)); |
||
| 508 | if ( map->sw_data == NULL ) { |
||
| 509 | SDL_FreeBlitMap(map); |
||
| 510 | SDL_OutOfMemory(); |
||
| 511 | return(NULL); |
||
| 512 | } |
||
| 513 | memset(map->sw_data, 0, sizeof(*map->sw_data)); |
||
| 514 | |||
| 515 | /* It's ready to go */ |
||
| 516 | return(map); |
||
| 517 | } |
||
| 518 | void SDL_InvalidateMap(SDL_BlitMap *map) |
||
| 519 | { |
||
| 520 | if ( ! map ) { |
||
| 521 | return; |
||
| 522 | } |
||
| 523 | map->dst = NULL; |
||
| 524 | map->format_version = (unsigned int)-1; |
||
| 525 | if ( map->table ) { |
||
| 526 | free(map->table); |
||
| 527 | map->table = NULL; |
||
| 528 | } |
||
| 529 | } |
||
| 530 | int SDL_MapSurface (SDL_Surface *src, SDL_Surface *dst) |
||
| 531 | { |
||
| 532 | SDL_PixelFormat *srcfmt; |
||
| 533 | SDL_PixelFormat *dstfmt; |
||
| 534 | SDL_BlitMap *map; |
||
| 535 | |||
| 536 | /* Clear out any previous mapping */ |
||
| 537 | map = src->map; |
||
| 538 | if ( (src->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { |
||
| 539 | SDL_UnRLESurface(src, 1); |
||
| 540 | } |
||
| 541 | SDL_InvalidateMap(map); |
||
| 542 | |||
| 543 | /* Figure out what kind of mapping we're doing */ |
||
| 544 | map->identity = 0; |
||
| 545 | srcfmt = src->format; |
||
| 546 | dstfmt = dst->format; |
||
| 547 | switch (srcfmt->BytesPerPixel) { |
||
| 548 | case 1: |
||
| 549 | switch (dstfmt->BytesPerPixel) { |
||
| 550 | case 1: |
||
| 551 | /* Palette --> Palette */ |
||
| 552 | /* If both SDL_HWSURFACE, assume have same palette */ |
||
| 553 | if ( ((src->flags & SDL_HWSURFACE) == SDL_HWSURFACE) && |
||
| 554 | ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) ) { |
||
| 555 | map->identity = 1; |
||
| 556 | } else { |
||
| 557 | map->table = Map1to1(srcfmt->palette, |
||
| 558 | dstfmt->palette, &map->identity); |
||
| 559 | } |
||
| 560 | if ( ! map->identity ) { |
||
| 561 | if ( map->table == NULL ) { |
||
| 562 | return(-1); |
||
| 563 | } |
||
| 564 | } |
||
| 565 | if (srcfmt->BitsPerPixel!=dstfmt->BitsPerPixel) |
||
| 566 | map->identity = 0; |
||
| 567 | break; |
||
| 568 | |||
| 569 | default: |
||
| 570 | /* Palette --> BitField */ |
||
| 571 | map->table = Map1toN(srcfmt->palette, dstfmt); |
||
| 572 | if ( map->table == NULL ) { |
||
| 573 | return(-1); |
||
| 574 | } |
||
| 575 | break; |
||
| 576 | } |
||
| 577 | break; |
||
| 578 | default: |
||
| 579 | switch (dstfmt->BytesPerPixel) { |
||
| 580 | case 1: |
||
| 581 | /* BitField --> Palette */ |
||
| 582 | map->table = MapNto1(srcfmt, |
||
| 583 | dstfmt->palette, &map->identity); |
||
| 584 | if ( ! map->identity ) { |
||
| 585 | if ( map->table == NULL ) { |
||
| 586 | return(-1); |
||
| 587 | } |
||
| 588 | } |
||
| 589 | map->identity = 0; /* Don't optimize to copy */ |
||
| 590 | break; |
||
| 591 | default: |
||
| 592 | /* BitField --> BitField */ |
||
| 593 | if ( FORMAT_EQUAL(srcfmt, dstfmt) ) |
||
| 594 | map->identity = 1; |
||
| 595 | break; |
||
| 596 | } |
||
| 597 | break; |
||
| 598 | } |
||
| 599 | |||
| 600 | map->dst = dst; |
||
| 601 | map->format_version = dst->format_version; |
||
| 602 | |||
| 603 | /* Choose your blitters wisely */ |
||
| 604 | return(SDL_CalculateBlit(src)); |
||
| 605 | } |
||
| 606 | void SDL_FreeBlitMap(SDL_BlitMap *map) |
||
| 607 | { |
||
| 608 | if ( map ) { |
||
| 609 | SDL_InvalidateMap(map); |
||
| 610 | if ( map->sw_data != NULL ) { |
||
| 611 | free(map->sw_data); |
||
| 612 | } |
||
| 613 | free(map); |
||
| 614 | } |
||
| 615 | } |