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  73 NAME="SDLSETGAMMA"
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  75 >SDL_SetGamma</H1
  76 ><DIV
  77 CLASS="REFNAMEDIV"
  78 ><A
  79 NAME="AEN1569"
  80 ></A
  81 ><H2
  82 >Name</H2
  83 >SDL_SetGamma&nbsp;--&nbsp;Sets the color gamma function for the display</DIV
  84 ><DIV
  85 CLASS="REFSYNOPSISDIV"
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  87 NAME="AEN1572"
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  90 >Synopsis</H2
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  98 ><PRE
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 100 >#include "SDL.h"</PRE
 101 ><P
 102 ><CODE
 103 ><CODE
 104 CLASS="FUNCDEF"
 105 >int <B
 106 CLASS="FSFUNC"
 107 >SDL_SetGamma</B
 108 ></CODE
 109 >(float redgamma, float greengamma, float bluegamma);</CODE
 110 ></P
 111 ><P
 112 ></P
 113 ></DIV
 114 ></DIV
 115 ><DIV
 116 CLASS="REFSECT1"
 117 ><A
 118 NAME="AEN1579"
 119 ></A
 120 ><H2
 121 >Description</H2
 122 ><P
 123 >Sets the "gamma function" for the display of each color component.  Gamma
 124 controls the brightness/contrast of colors displayed on the screen.
 125 A gamma value of <TT
 126 CLASS="CONSTANT"
 127 >1.0</TT
 128 > is identity (i.e., no adjustment
 129 is made).</P
 130 ><P
 131 >This function adjusts the gamma based on the "gamma function" parameter,
 132 you can directly specify lookup tables for gamma adjustment with
 133 <A
 134 HREF="sdlsetgammaramp.html"
 135 >SDL_SetGammaRamp</A
 136 >.</P
 137 ><P
 138 >Not all display hardware is able to change gamma.</P
 139 ></DIV
 140 ><DIV
 141 CLASS="REFSECT1"
 142 ><A
 143 NAME="AEN1586"
 144 ></A
 145 ><H2
 146 >Return Value</H2
 147 ><P
 148 >Returns -1 on error (or if gamma adjustment is not supported).</P
 149 ></DIV
 150 ><DIV
 151 CLASS="REFSECT1"
 152 ><A
 153 NAME="AEN1589"
 154 ></A
 155 ><H2
 156 >See Also</H2
 157 ><P
 158 ><A
 159 HREF="sdlgetgammaramp.html"
 160 >SDL_GetGammaRamp</A
 161 >
 162 <A
 163 HREF="sdlsetgammaramp.html"
 164 >SDL_SetGammaRamp</A
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