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     72 ><A
     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"
     88 ></A
     89 ><H2
     90 >Synopsis</H2
     91 ><DIV
     92 CLASS="FUNCSYNOPSIS"
     93 ><A
     94 NAME="AEN2682"
     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 >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
    181 ></DIV
    182 ><DIV
    183 CLASS="REFSECT1"
    184 ><A
    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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