Mercurial > sdl-ios-xcode
annotate src/video/SDL_pixels.c @ 1027:c69697a85412
Clarified the code in the pixel format allocation
Added support for direct color 8-bpp modes.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 12 Jan 2005 19:38:24 +0000 |
| parents | 3bf4103b2b89 |
| children | e9d23bb80140 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
769
b8d311d90021
Updated copyright information for 2004 (Happy New Year!)
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3 Copyright (C) 1997-2004 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 of the License, or (at your option) any later version. | |
| 9 | |
| 10 This library is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
252
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Updated the source with the correct e-mail address
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20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* General (mostly internal) pixel/color manipulation routines for SDL */ | |
| 29 | |
| 30 #include <stdio.h> | |
| 31 #include <stdlib.h> | |
| 32 #include <string.h> | |
| 33 | |
| 34 #include "SDL_error.h" | |
| 35 #include "SDL_endian.h" | |
| 36 #include "SDL_video.h" | |
| 37 #include "SDL_sysvideo.h" | |
| 38 #include "SDL_blit.h" | |
| 39 #include "SDL_pixels_c.h" | |
| 40 #include "SDL_RLEaccel_c.h" | |
| 41 | |
| 42 /* Helper functions */ | |
| 43 /* | |
| 44 * Allocate a pixel format structure and fill it according to the given info. | |
| 45 */ | |
| 46 SDL_PixelFormat *SDL_AllocFormat(int bpp, | |
| 47 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) | |
| 48 { | |
| 49 SDL_PixelFormat *format; | |
| 50 Uint32 mask; | |
| 51 | |
| 52 /* Allocate an empty pixel format structure */ | |
| 53 format = malloc(sizeof(*format)); | |
| 54 if ( format == NULL ) { | |
| 55 SDL_OutOfMemory(); | |
| 56 return(NULL); | |
| 57 } | |
| 58 memset(format, 0, sizeof(*format)); | |
| 59 format->alpha = SDL_ALPHA_OPAQUE; | |
| 60 | |
| 61 /* Set up the format */ | |
| 62 format->BitsPerPixel = bpp; | |
| 63 format->BytesPerPixel = (bpp+7)/8; | |
|
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64 if ( Rmask || Bmask || Gmask ) { /* Packed pixels with custom mask */ |
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c69697a85412
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65 format->palette = NULL; |
|
c69697a85412
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66 format->Rshift = 0; |
|
c69697a85412
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67 format->Rloss = 8; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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68 if ( Rmask ) { |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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69 for ( mask = Rmask; !(mask&0x01); mask >>= 1 ) |
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c69697a85412
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70 ++format->Rshift; |
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c69697a85412
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71 for ( ; (mask&0x01); mask >>= 1 ) |
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c69697a85412
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parents:
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72 --format->Rloss; |
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c69697a85412
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parents:
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73 } |
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c69697a85412
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parents:
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74 format->Gshift = 0; |
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c69697a85412
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parents:
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75 format->Gloss = 8; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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76 if ( Gmask ) { |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
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77 for ( mask = Gmask; !(mask&0x01); mask >>= 1 ) |
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c69697a85412
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parents:
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78 ++format->Gshift; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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79 for ( ; (mask&0x01); mask >>= 1 ) |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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80 --format->Gloss; |
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c69697a85412
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81 } |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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82 format->Bshift = 0; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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83 format->Bloss = 8; |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
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84 if ( Bmask ) { |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
changeset
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85 for ( mask = Bmask; !(mask&0x01); mask >>= 1 ) |
|
c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
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86 ++format->Bshift; |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
changeset
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87 for ( ; (mask&0x01); mask >>= 1 ) |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
changeset
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88 --format->Bloss; |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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89 } |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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90 format->Ashift = 0; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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91 format->Aloss = 8; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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92 if ( Amask ) { |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
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93 for ( mask = Amask; !(mask&0x01); mask >>= 1 ) |
|
c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
changeset
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94 ++format->Ashift; |
|
c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
changeset
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95 for ( ; (mask&0x01); mask >>= 1 ) |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
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96 --format->Aloss; |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
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97 } |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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98 format->Rmask = Rmask; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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99 format->Gmask = Gmask; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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diff
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100 format->Bmask = Bmask; |
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c69697a85412
Clarified the code in the pixel format allocation
Sam Lantinga <slouken@libsdl.org>
parents:
997
diff
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101 format->Amask = Amask; |
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c69697a85412
Clarified the code in the pixel format allocation
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parents:
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102 } else if ( bpp > 8 ) { /* Packed pixels with standard mask */ |
| 0 | 103 /* R-G-B */ |
| 104 if ( bpp > 24 ) | |
| 105 bpp = 24; | |
| 106 format->Rloss = 8-(bpp/3); | |
| 107 format->Gloss = 8-(bpp/3)-(bpp%3); | |
| 108 format->Bloss = 8-(bpp/3); | |
| 109 format->Rshift = ((bpp/3)+(bpp%3))+(bpp/3); | |
| 110 format->Gshift = (bpp/3); | |
| 111 format->Bshift = 0; | |
| 112 format->Rmask = ((0xFF>>format->Rloss)<<format->Rshift); | |
| 113 format->Gmask = ((0xFF>>format->Gloss)<<format->Gshift); | |
| 114 format->Bmask = ((0xFF>>format->Bloss)<<format->Bshift); | |
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115 } else { /* Palettized mode */ |
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c69697a85412
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116 int i, ncolors = 1; |
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c69697a85412
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117 for ( i = 0; i < bpp; ++i ) { |
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c69697a85412
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118 ncolors *= 2; |
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c69697a85412
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119 } |
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c69697a85412
Clarified the code in the pixel format allocation
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120 format->palette = (SDL_Palette *)malloc(sizeof(SDL_Palette)); |
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c69697a85412
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121 if ( format->palette == NULL ) { |
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c69697a85412
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122 SDL_FreeFormat(format); |
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123 SDL_OutOfMemory(); |
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124 return(NULL); |
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125 } |
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126 (format->palette)->ncolors = ncolors; |
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127 (format->palette)->colors = (SDL_Color *)malloc( |
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128 (format->palette)->ncolors*sizeof(SDL_Color)); |
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129 if ( (format->palette)->colors == NULL ) { |
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130 SDL_FreeFormat(format); |
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131 SDL_OutOfMemory(); |
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132 return(NULL); |
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133 } |
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134 if ( ncolors == 2 ) { |
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135 /* Create a black and white bitmap palette */ |
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136 format->palette->colors[0].r = 0xFF; |
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137 format->palette->colors[0].g = 0xFF; |
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138 format->palette->colors[0].b = 0xFF; |
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139 format->palette->colors[1].r = 0x00; |
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140 format->palette->colors[1].g = 0x00; |
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141 format->palette->colors[1].b = 0x00; |
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142 } else { |
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143 /* Create an empty palette */ |
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144 memset((format->palette)->colors, 0, |
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145 (format->palette)->ncolors*sizeof(SDL_Color)); |
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146 } |
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147 |
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148 /* Palettized formats have no mask info */ |
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149 format->Rloss = 8; |
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150 format->Gloss = 8; |
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151 format->Bloss = 8; |
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152 format->Aloss = 8; |
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153 format->Rshift = 0; |
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154 format->Gshift = 0; |
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155 format->Bshift = 0; |
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156 format->Ashift = 0; |
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157 format->Rmask = 0; |
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158 format->Gmask = 0; |
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159 format->Bmask = 0; |
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160 format->Amask = 0; |
| 0 | 161 } |
| 162 return(format); | |
| 163 } | |
| 164 SDL_PixelFormat *SDL_ReallocFormat(SDL_Surface *surface, int bpp, | |
| 165 Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) | |
| 166 { | |
| 167 if ( surface->format ) { | |
| 168 SDL_FreeFormat(surface->format); | |
| 169 SDL_FormatChanged(surface); | |
| 170 } | |
| 171 surface->format = SDL_AllocFormat(bpp, Rmask, Gmask, Bmask, Amask); | |
| 172 return surface->format; | |
| 173 } | |
| 174 | |
| 175 /* | |
| 176 * Change any previous mappings from/to the new surface format | |
| 177 */ | |
| 178 void SDL_FormatChanged(SDL_Surface *surface) | |
| 179 { | |
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180 static int format_version = 0; |
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181 ++format_version; |
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182 if ( format_version < 0 ) { /* It wrapped... */ |
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183 format_version = 1; |
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184 } |
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185 surface->format_version = format_version; |
| 0 | 186 SDL_InvalidateMap(surface->map); |
| 187 } | |
| 188 /* | |
| 189 * Free a previously allocated format structure | |
| 190 */ | |
| 191 void SDL_FreeFormat(SDL_PixelFormat *format) | |
| 192 { | |
| 193 if ( format ) { | |
| 194 if ( format->palette ) { | |
| 195 if ( format->palette->colors ) { | |
| 196 free(format->palette->colors); | |
| 197 } | |
| 198 free(format->palette); | |
| 199 } | |
| 200 free(format); | |
| 201 } | |
| 202 } | |
| 203 /* | |
| 204 * Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors | |
| 205 */ | |
| 206 void SDL_DitherColors(SDL_Color *colors, int bpp) | |
| 207 { | |
| 208 int i; | |
| 209 if(bpp != 8) | |
| 210 return; /* only 8bpp supported right now */ | |
| 211 | |
| 212 for(i = 0; i < 256; i++) { | |
| 213 int r, g, b; | |
| 214 /* map each bit field to the full [0, 255] interval, | |
| 215 so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */ | |
| 216 r = i & 0xe0; | |
| 217 r |= r >> 3 | r >> 6; | |
| 218 colors[i].r = r; | |
| 219 g = (i << 3) & 0xe0; | |
| 220 g |= g >> 3 | g >> 6; | |
| 221 colors[i].g = g; | |
| 222 b = i & 0x3; | |
| 223 b |= b << 2; | |
| 224 b |= b << 4; | |
| 225 colors[i].b = b; | |
| 226 } | |
| 227 } | |
| 228 /* | |
| 229 * Calculate the pad-aligned scanline width of a surface | |
| 230 */ | |
| 231 Uint16 SDL_CalculatePitch(SDL_Surface *surface) | |
| 232 { | |
| 233 Uint16 pitch; | |
| 234 | |
| 235 /* Surface should be 4-byte aligned for speed */ | |
| 236 pitch = surface->w*surface->format->BytesPerPixel; | |
| 237 switch (surface->format->BitsPerPixel) { | |
| 238 case 1: | |
| 239 pitch = (pitch+7)/8; | |
| 240 break; | |
| 241 case 4: | |
| 242 pitch = (pitch+1)/2; | |
| 243 break; | |
| 244 default: | |
| 245 break; | |
| 246 } | |
| 247 pitch = (pitch + 3) & ~3; /* 4-byte aligning */ | |
| 248 return(pitch); | |
| 249 } | |
| 250 /* | |
| 251 * Match an RGB value to a particular palette index | |
| 252 */ | |
| 253 Uint8 SDL_FindColor(SDL_Palette *pal, Uint8 r, Uint8 g, Uint8 b) | |
| 254 { | |
| 255 /* Do colorspace distance matching */ | |
| 256 unsigned int smallest; | |
| 257 unsigned int distance; | |
| 258 int rd, gd, bd; | |
| 259 int i; | |
| 260 Uint8 pixel=0; | |
| 261 | |
| 262 smallest = ~0; | |
| 263 for ( i=0; i<pal->ncolors; ++i ) { | |
| 264 rd = pal->colors[i].r - r; | |
| 265 gd = pal->colors[i].g - g; | |
| 266 bd = pal->colors[i].b - b; | |
| 267 distance = (rd*rd)+(gd*gd)+(bd*bd); | |
| 268 if ( distance < smallest ) { | |
| 269 pixel = i; | |
| 270 if ( distance == 0 ) { /* Perfect match! */ | |
| 271 break; | |
| 272 } | |
| 273 smallest = distance; | |
| 274 } | |
| 275 } | |
| 276 return(pixel); | |
| 277 } | |
| 278 | |
| 279 /* Find the opaque pixel value corresponding to an RGB triple */ | |
| 280 Uint32 SDL_MapRGB(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b) | |
| 281 { | |
| 282 if ( format->palette == NULL ) { | |
| 283 return (r >> format->Rloss) << format->Rshift | |
| 284 | (g >> format->Gloss) << format->Gshift | |
| 285 | (b >> format->Bloss) << format->Bshift | |
| 286 | format->Amask; | |
| 287 } else { | |
| 288 return SDL_FindColor(format->palette, r, g, b); | |
| 289 } | |
| 290 } | |
| 291 | |
| 292 /* Find the pixel value corresponding to an RGBA quadruple */ | |
| 293 Uint32 SDL_MapRGBA(SDL_PixelFormat *format, Uint8 r, Uint8 g, Uint8 b, Uint8 a) | |
| 294 { | |
| 295 if ( format->palette == NULL ) { | |
| 296 return (r >> format->Rloss) << format->Rshift | |
| 297 | (g >> format->Gloss) << format->Gshift | |
| 298 | (b >> format->Bloss) << format->Bshift | |
| 299 | ((a >> format->Aloss) << format->Ashift & format->Amask); | |
| 300 } else { | |
| 301 return SDL_FindColor(format->palette, r, g, b); | |
| 302 } | |
| 303 } | |
| 304 | |
| 305 void SDL_GetRGBA(Uint32 pixel, SDL_PixelFormat *fmt, | |
| 306 Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a) | |
| 307 { | |
| 308 if ( fmt->palette == NULL ) { | |
| 309 /* | |
| 310 * This makes sure that the result is mapped to the | |
| 311 * interval [0..255], and the maximum value for each | |
| 312 * component is 255. This is important to make sure | |
| 313 * that white is indeed reported as (255, 255, 255), | |
| 314 * and that opaque alpha is 255. | |
| 315 * This only works for RGB bit fields at least 4 bit | |
| 316 * wide, which is almost always the case. | |
| 317 */ | |
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318 unsigned v; |
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319 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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320 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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321 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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322 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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323 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
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324 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
| 0 | 325 if(fmt->Amask) { |
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326 v = (pixel & fmt->Amask) >> fmt->Ashift; |
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327 *a = (v << fmt->Aloss) + (v >> (8 - (fmt->Aloss << 1))); |
| 695 | 328 } else { |
| 0 | 329 *a = SDL_ALPHA_OPAQUE; |
| 695 | 330 } |
| 0 | 331 } else { |
| 332 *r = fmt->palette->colors[pixel].r; | |
| 333 *g = fmt->palette->colors[pixel].g; | |
| 334 *b = fmt->palette->colors[pixel].b; | |
| 335 *a = SDL_ALPHA_OPAQUE; | |
| 336 } | |
| 337 } | |
| 338 | |
| 339 void SDL_GetRGB(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r,Uint8 *g,Uint8 *b) | |
| 340 { | |
| 341 if ( fmt->palette == NULL ) { | |
| 342 /* the note for SDL_GetRGBA above applies here too */ | |
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343 unsigned v; |
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344 v = (pixel & fmt->Rmask) >> fmt->Rshift; |
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345 *r = (v << fmt->Rloss) + (v >> (8 - (fmt->Rloss << 1))); |
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346 v = (pixel & fmt->Gmask) >> fmt->Gshift; |
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347 *g = (v << fmt->Gloss) + (v >> (8 - (fmt->Gloss << 1))); |
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348 v = (pixel & fmt->Bmask) >> fmt->Bshift; |
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349 *b = (v << fmt->Bloss) + (v >> (8 - (fmt->Bloss << 1))); |
| 0 | 350 } else { |
| 351 *r = fmt->palette->colors[pixel].r; | |
| 352 *g = fmt->palette->colors[pixel].g; | |
| 353 *b = fmt->palette->colors[pixel].b; | |
| 354 } | |
| 355 } | |
| 356 | |
| 357 /* Apply gamma to a set of colors - this is easy. :) */ | |
| 358 void SDL_ApplyGamma(Uint16 *gamma, SDL_Color *colors, SDL_Color *output, | |
| 359 int ncolors) | |
| 360 { | |
| 361 int i; | |
| 362 | |
| 363 for ( i=0; i<ncolors; ++i ) { | |
| 364 output[i].r = gamma[0*256 + colors[i].r] >> 8; | |
| 365 output[i].g = gamma[1*256 + colors[i].g] >> 8; | |
| 366 output[i].b = gamma[2*256 + colors[i].b] >> 8; | |
| 367 } | |
| 368 } | |
| 369 | |
| 370 /* Map from Palette to Palette */ | |
| 371 static Uint8 *Map1to1(SDL_Palette *src, SDL_Palette *dst, int *identical) | |
| 372 { | |
| 373 Uint8 *map; | |
| 374 int i; | |
| 375 | |
| 376 if ( identical ) { | |
| 377 if ( src->ncolors <= dst->ncolors ) { | |
| 378 /* If an identical palette, no need to map */ | |
| 379 if ( memcmp(src->colors, dst->colors, src->ncolors* | |
| 380 sizeof(SDL_Color)) == 0 ) { | |
| 381 *identical = 1; | |
| 382 return(NULL); | |
| 383 } | |
| 384 } | |
| 385 *identical = 0; | |
| 386 } | |
| 387 map = (Uint8 *)malloc(src->ncolors); | |
| 388 if ( map == NULL ) { | |
| 389 SDL_OutOfMemory(); | |
| 390 return(NULL); | |
| 391 } | |
| 392 for ( i=0; i<src->ncolors; ++i ) { | |
| 393 map[i] = SDL_FindColor(dst, | |
| 394 src->colors[i].r, src->colors[i].g, src->colors[i].b); | |
| 395 } | |
| 396 return(map); | |
| 397 } | |
| 398 /* Map from Palette to BitField */ | |
| 399 static Uint8 *Map1toN(SDL_Palette *src, SDL_PixelFormat *dst) | |
| 400 { | |
| 401 Uint8 *map; | |
| 402 int i; | |
| 403 int bpp; | |
| 50 | 404 unsigned alpha; |
| 0 | 405 |
| 406 bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel); | |
| 407 map = (Uint8 *)malloc(src->ncolors*bpp); | |
| 408 if ( map == NULL ) { | |
| 409 SDL_OutOfMemory(); | |
| 410 return(NULL); | |
| 411 } | |
| 412 | |
| 50 | 413 alpha = dst->Amask ? SDL_ALPHA_OPAQUE : 0; |
| 0 | 414 /* We memory copy to the pixel map so the endianness is preserved */ |
| 415 for ( i=0; i<src->ncolors; ++i ) { | |
| 416 ASSEMBLE_RGBA(&map[i*bpp], dst->BytesPerPixel, dst, | |
| 417 src->colors[i].r, src->colors[i].g, | |
| 50 | 418 src->colors[i].b, alpha); |
| 0 | 419 } |
| 420 return(map); | |
| 421 } | |
| 422 /* Map from BitField to Dithered-Palette to Palette */ | |
| 423 static Uint8 *MapNto1(SDL_PixelFormat *src, SDL_Palette *dst, int *identical) | |
| 424 { | |
| 425 /* Generate a 256 color dither palette */ | |
| 426 SDL_Palette dithered; | |
| 427 SDL_Color colors[256]; | |
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428 |
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429 /* SDL_DitherColors does not initialize the 'unused' component of colors, |
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430 but Map1to1 compares it against dst, so we should initialize it. */ |
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431 memset(colors, 0, sizeof(colors)); |
| 0 | 432 |
| 433 dithered.ncolors = 256; | |
| 434 SDL_DitherColors(colors, 8); | |
| 435 dithered.colors = colors; | |
| 436 return(Map1to1(&dithered, dst, identical)); | |
| 437 } | |
| 438 | |
| 439 SDL_BlitMap *SDL_AllocBlitMap(void) | |
| 440 { | |
| 441 SDL_BlitMap *map; | |
| 442 | |
| 443 /* Allocate the empty map */ | |
| 444 map = (SDL_BlitMap *)malloc(sizeof(*map)); | |
| 445 if ( map == NULL ) { | |
| 446 SDL_OutOfMemory(); | |
| 447 return(NULL); | |
| 448 } | |
| 449 memset(map, 0, sizeof(*map)); | |
| 450 | |
| 451 /* Allocate the software blit data */ | |
| 452 map->sw_data = (struct private_swaccel *)malloc(sizeof(*map->sw_data)); | |
| 453 if ( map->sw_data == NULL ) { | |
| 454 SDL_FreeBlitMap(map); | |
| 455 SDL_OutOfMemory(); | |
| 456 return(NULL); | |
| 457 } | |
| 458 memset(map->sw_data, 0, sizeof(*map->sw_data)); | |
| 459 | |
| 460 /* It's ready to go */ | |
| 461 return(map); | |
| 462 } | |
| 463 void SDL_InvalidateMap(SDL_BlitMap *map) | |
| 464 { | |
| 465 if ( ! map ) { | |
| 466 return; | |
| 467 } | |
| 468 map->dst = NULL; | |
| 469 map->format_version = (unsigned int)-1; | |
| 470 if ( map->table ) { | |
| 471 free(map->table); | |
| 472 map->table = NULL; | |
| 473 } | |
| 474 } | |
| 475 int SDL_MapSurface (SDL_Surface *src, SDL_Surface *dst) | |
| 476 { | |
| 477 SDL_PixelFormat *srcfmt; | |
| 478 SDL_PixelFormat *dstfmt; | |
| 479 SDL_BlitMap *map; | |
| 480 | |
| 481 /* Clear out any previous mapping */ | |
| 482 map = src->map; | |
| 483 if ( (src->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { | |
| 484 SDL_UnRLESurface(src, 1); | |
| 485 } | |
| 486 SDL_InvalidateMap(map); | |
| 487 | |
| 488 /* Figure out what kind of mapping we're doing */ | |
| 489 map->identity = 0; | |
| 490 srcfmt = src->format; | |
| 491 dstfmt = dst->format; | |
| 492 switch (srcfmt->BytesPerPixel) { | |
| 493 case 1: | |
| 494 switch (dstfmt->BytesPerPixel) { | |
| 495 case 1: | |
| 496 /* Palette --> Palette */ | |
| 497 /* If both SDL_HWSURFACE, assume have same palette */ | |
| 498 if ( ((src->flags & SDL_HWSURFACE) == SDL_HWSURFACE) && | |
| 499 ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) ) { | |
| 500 map->identity = 1; | |
| 501 } else { | |
| 502 map->table = Map1to1(srcfmt->palette, | |
| 503 dstfmt->palette, &map->identity); | |
| 504 } | |
| 505 if ( ! map->identity ) { | |
| 506 if ( map->table == NULL ) { | |
| 507 return(-1); | |
| 508 } | |
| 509 } | |
| 510 if (srcfmt->BitsPerPixel!=dstfmt->BitsPerPixel) | |
| 511 map->identity = 0; | |
| 512 break; | |
| 513 | |
| 514 default: | |
| 515 /* Palette --> BitField */ | |
| 516 map->table = Map1toN(srcfmt->palette, dstfmt); | |
| 517 if ( map->table == NULL ) { | |
| 518 return(-1); | |
| 519 } | |
| 520 break; | |
| 521 } | |
| 522 break; | |
| 523 default: | |
| 524 switch (dstfmt->BytesPerPixel) { | |
| 525 case 1: | |
| 526 /* BitField --> Palette */ | |
| 527 map->table = MapNto1(srcfmt, | |
| 528 dstfmt->palette, &map->identity); | |
| 529 if ( ! map->identity ) { | |
| 530 if ( map->table == NULL ) { | |
| 531 return(-1); | |
| 532 } | |
| 533 } | |
| 534 map->identity = 0; /* Don't optimize to copy */ | |
| 535 break; | |
| 536 default: | |
| 537 /* BitField --> BitField */ | |
| 538 if ( FORMAT_EQUAL(srcfmt, dstfmt) ) | |
| 539 map->identity = 1; | |
| 540 break; | |
| 541 } | |
| 542 break; | |
| 543 } | |
| 544 | |
| 545 map->dst = dst; | |
| 546 map->format_version = dst->format_version; | |
| 547 | |
| 548 /* Choose your blitters wisely */ | |
| 549 return(SDL_CalculateBlit(src)); | |
| 550 } | |
| 551 void SDL_FreeBlitMap(SDL_BlitMap *map) | |
| 552 { | |
| 553 if ( map ) { | |
| 554 SDL_InvalidateMap(map); | |
| 555 if ( map->sw_data != NULL ) { | |
| 556 free(map->sw_data); | |
| 557 } | |
| 558 free(map); | |
| 559 } | |
| 560 } |