[sdl_omap.git] / docs / html / sdlglgetprocaddress.html

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>SDL_GL_GetProcAddress</TITLE
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><H1
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>SDL_GL_GetProcAddress</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2678"
></A
><H2
>Name</H2
>SDL_GL_GetProcAddress&nbsp;--&nbsp;Get the address of a GL function</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2681"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2682"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void *<B
CLASS="FSFUNC"
>SDL_GL_GetProcAddress</B
></CODE
>(const char* proc);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2688"
></A
><H2
>Description</H2
><P
>Returns the address of the GL function <TT
CLASS="PARAMETER"
><I
>proc</I
></TT
>, or <SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
> if the function is not found. If the GL library is loaded at runtime, with <A
HREF="sdlglloadlibrary.html"
><TT
CLASS="FUNCTION"
>SDL_GL_LoadLibrary</TT
></A
>, then <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>all</I
></SPAN
> GL functions must be retrieved this way. Usually this is used to retrieve function pointers to OpenGL extensions.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2696"
></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef void (*GL_ActiveTextureARB_Func)(unsigned int);
GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0;
int has_multitexture=1;
.
.
.
/* Get function pointer */
glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB");

/* Check for a valid function ptr */
if(!glActiveTextureARB_ptr){
  fprintf(stderr, "Multitexture Extensions not present.\n");
  has_multitexture=0;
}
.
.
.
.
if(has_multitexture){
  glActiveTextureARB_ptr(GL_TEXTURE0_ARB);
  .
  .
}
else{
  .
  .
}</PRE
></DIV
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><H2
>See Also</H2
><P
><A
HREF="sdlglloadlibrary.html"
><TT
CLASS="FUNCTION"
>SDL_GL_LoadLibrary</TT
></A
></P
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Commit	Line	Data
e14743d1	1	<HTML
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	3	><TITLE
	4	>SDL_GL_GetProcAddress</TITLE
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	7	CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
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	44	WIDTH="10%"
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70	WIDTH="100%"></DIV
71	><H1
72	><A
73	NAME="SDLGLGETPROCADDRESS"
74	></A
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 -- 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"
186	></A
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
196	></P
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262	>