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  73 NAME="SDLGLGETPROCADDRESS"
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  75 >SDL_GL_GetProcAddress</H1
  76 ><DIV
  77 CLASS="REFNAMEDIV"
  78 ><A
  79 NAME="AEN2678"
  80 ></A
  81 ><H2
  82 >Name</H2
  83 >SDL_GL_GetProcAddress&nbsp;--&nbsp;Get the address of a GL function</DIV
  84 ><DIV
  85 CLASS="REFSYNOPSISDIV"
  86 ><A
  87 NAME="AEN2681"
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  89 ><H2
  90 >Synopsis</H2
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  94 NAME="AEN2682"
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  96 ><P
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  98 ><PRE
  99 CLASS="FUNCSYNOPSISINFO"
 100 >#include "SDL.h"</PRE
 101 ><P
 102 ><CODE
 103 ><CODE
 104 CLASS="FUNCDEF"
 105 >void *<B
 106 CLASS="FSFUNC"
 107 >SDL_GL_GetProcAddress</B
 108 ></CODE
 109 >(const char* proc);</CODE
 110 ></P
 111 ><P
 112 ></P
 113 ></DIV
 114 ></DIV
 115 ><DIV
 116 CLASS="REFSECT1"
 117 ><A
 118 NAME="AEN2688"
 119 ></A
 120 ><H2
 121 >Description</H2
 122 ><P
 123 >Returns the address of the GL function <TT
 124 CLASS="PARAMETER"
 125 ><I
 126 >proc</I
 127 ></TT
 128 >, or <SPAN
 129 CLASS="RETURNVALUE"
 130 >NULL</SPAN
 131 > if the function is not found. If the GL library is loaded at runtime, with <A
 132 HREF="sdlglloadlibrary.html"
 133 ><TT
 134 CLASS="FUNCTION"
 135 >SDL_GL_LoadLibrary</TT
 136 ></A
 137 >, then <SPAN
 138 CLASS="emphasis"
 139 ><I
 140 CLASS="EMPHASIS"
 141 >all</I
 142 ></SPAN
 143 > GL functions must be retrieved this way. Usually this is used to retrieve function pointers to OpenGL extensions.</P
 144 ></DIV
 145 ><DIV
 146 CLASS="REFSECT1"
 147 ><A
 148 NAME="AEN2696"
 149 ></A
 150 ><H2
 151 >Example</H2
 152 ><PRE
 153 CLASS="PROGRAMLISTING"
 154 >typedef void (*GL_ActiveTextureARB_Func)(unsigned int);
 155 GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0;
 156 int has_multitexture=1;
 157 .
 158 .
 159 .
 160 /* Get function pointer */
 161 glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB");
 162
 163 /* Check for a valid function ptr */
 164 if(!glActiveTextureARB_ptr){
 165   fprintf(stderr, "Multitexture Extensions not present.\n");
 166   has_multitexture=0;
 167 }
 168 .
 169 .
 170 .
 171 .
 172 if(has_multitexture){
 173   glActiveTextureARB_ptr(GL_TEXTURE0_ARB);
 174   .
 175   .
 176 }
 177 else{
 178   .
 179   .
 180 }</PRE
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 185 NAME="AEN2699"
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 187 ><H2
 188 >See Also</H2
 189 ><P
 190 ><A
 191 HREF="sdlglloadlibrary.html"
 192 ><TT
 193 CLASS="FUNCTION"
 194 >SDL_GL_LoadLibrary</TT
 195 ></A
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