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  71 ><H1
  72 ><A
  73 NAME="SDLSETCOLORS"
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  75 >SDL_SetColors</H1
  76 ><DIV
  77 CLASS="REFNAMEDIV"
  78 ><A
  79 NAME="AEN1462"
  80 ></A
  81 ><H2
  82 >Name</H2
  83 >SDL_SetColors&nbsp;--&nbsp;Sets a portion of the colormap for the given 8-bit surface.</DIV
  84 ><DIV
  85 CLASS="REFSYNOPSISDIV"
  86 ><A
  87 NAME="AEN1465"
  88 ></A
  89 ><H2
  90 >Synopsis</H2
  91 ><DIV
  92 CLASS="FUNCSYNOPSIS"
  93 ><A
  94 NAME="AEN1466"
  95 ></A
  96 ><P
  97 ></P
  98 ><PRE
  99 CLASS="FUNCSYNOPSISINFO"
 100 >#include "SDL.h"</PRE
 101 ><P
 102 ><CODE
 103 ><CODE
 104 CLASS="FUNCDEF"
 105 >int <B
 106 CLASS="FSFUNC"
 107 >SDL_SetColors</B
 108 ></CODE
 109 >(SDL_Surface *surface, SDL_Color *colors, int firstcolor, int ncolors);</CODE
 110 ></P
 111 ><P
 112 ></P
 113 ></DIV
 114 ></DIV
 115 ><DIV
 116 CLASS="REFSECT1"
 117 ><A
 118 NAME="AEN1472"
 119 ></A
 120 ><H2
 121 >Description</H2
 122 ><P
 123 >Sets a portion of the colormap for the given 8-bit surface.</P
 124 ><P
 125 >When <TT
 126 CLASS="PARAMETER"
 127 ><I
 128 >surface</I
 129 ></TT
 130 > is the surface associated with the current
 131 display, the display colormap will be updated with the requested colors.  If
 132 <TT
 133 CLASS="LITERAL"
 134 >SDL_HWPALETTE</TT
 135 > was set in <A
 136 HREF="sdlsetvideomode.html"
 137 >SDL_SetVideoMode</A
 138 > flags,
 139 <TT
 140 CLASS="FUNCTION"
 141 >SDL_SetColors</TT
 142 > will always return <SPAN
 143 CLASS="RETURNVALUE"
 144 >1</SPAN
 145 >,
 146 and the palette is guaranteed to be set the way you desire, even if the window
 147 colormap has to be warped or run under emulation.</P
 148 ><P
 149 >The color components of a
 150 <A
 151 HREF="sdlcolor.html"
 152 ><SPAN
 153 CLASS="STRUCTNAME"
 154 >SDL_Color</SPAN
 155 ></A
 156 >
 157 structure are 8-bits in size, giving you a total of 256<SUP
 158 >3</SUP
 159 >
 160 =16777216 colors.</P
 161 ><P
 162 >Palettized (8-bit) screen surfaces with the <TT
 163 CLASS="LITERAL"
 164 >SDL_HWPALETTE</TT
 165 >
 166 flag have two palettes, a logical palette that is used for mapping blits
 167 to/from the surface and a physical palette (that determines how the
 168 hardware will map the colors to the display). <TT
 169 CLASS="FUNCTION"
 170 >SDL_SetColors</TT
 171 >
 172 modifies both palettes (if present), and is equivalent to calling
 173 <A
 174 HREF="sdlsetpalette.html"
 175 >SDL_SetPalette</A
 176 > with the
 177 <TT
 178 CLASS="PARAMETER"
 179 ><I
 180 >flags</I
 181 ></TT
 182 > set to
 183 <TT
 184 CLASS="LITERAL"
 185 >(SDL_LOGPAL | SDL_PHYSPAL)</TT
 186 >.</P
 187 ></DIV
 188 ><DIV
 189 CLASS="REFSECT1"
 190 ><A
 191 NAME="AEN1491"
 192 ></A
 193 ><H2
 194 >Return Value</H2
 195 ><P
 196 >If <TT
 197 CLASS="PARAMETER"
 198 ><I
 199 >surface</I
 200 ></TT
 201 > is not a palettized surface, this function
 202 does nothing, returning <SPAN
 203 CLASS="RETURNVALUE"
 204 >0</SPAN
 205 >.  If all of the colors were set
 206 as passed to <TT
 207 CLASS="FUNCTION"
 208 >SDL_SetColors</TT
 209 >, it will return
 210 <SPAN
 211 CLASS="RETURNVALUE"
 212 >1</SPAN
 213 >.  If not all the color entries were set exactly as
 214 given, it will return <SPAN
 215 CLASS="RETURNVALUE"
 216 >0</SPAN
 217 >, and you should look at the
 218 surface palette to determine the actual color palette.</P
 219 ></DIV
 220 ><DIV
 221 CLASS="REFSECT1"
 222 ><A
 223 NAME="AEN1499"
 224 ></A
 225 ><H2
 226 >Example</H2
 227 ><PRE
 228 CLASS="PROGRAMLISTING"
 229 >/* Create a display surface with a grayscale palette */
 230 SDL_Surface *screen;
 231 SDL_Color colors[256];
 232 int i;
 233 .
 234 .
 235 .
 236 /* Fill colors with color information */
 237 for(i=0;i&#60;256;i++){
 238   colors[i].r=i;
 239   colors[i].g=i;
 240   colors[i].b=i;
 241 }
 242
 243 /* Create display */
 244 screen=SDL_SetVideoMode(640, 480, 8, SDL_HWPALETTE);
 245 if(!screen){
 246   printf("Couldn't set video mode: %s\n", SDL_GetError());
 247   exit(-1);
 248 }
 249
 250 /* Set palette */
 251 SDL_SetColors(screen, colors, 0, 256);
 252 .
 253 .
 254 .
 255 .</PRE
 256 ></DIV
 257 ><DIV
 258 CLASS="REFSECT1"
 259 ><A
 260 NAME="AEN1502"
 261 ></A
 262 ><H2
 263 >See Also</H2
 264 ><P
 265 ><A
 266 HREF="sdlcolor.html"
 267 ><SPAN
 268 CLASS="STRUCTNAME"
 269 >SDL_Color</SPAN
 270 ></A
 271 >
 272 <A
 273 HREF="sdlsurface.html"
 274 ><SPAN
 275 CLASS="STRUCTNAME"
 276 >SDL_Surface</SPAN
 277 ></A
 278 >,
 279 <A
 280 HREF="sdlsetpalette.html"
 281 ><TT
 282 CLASS="FUNCTION"
 283 >SDL_SetPalette</TT
 284 ></A
 285 >,
 286 <A
 287 HREF="sdlsetvideomode.html"
 288 ><TT
 289 CLASS="FUNCTION"
 290 >SDL_SetVideoMode</TT
 291 ></A
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