annotate docs/man3/SDL_GL_SetAttribute.3 @ 3880:74e828c64315 SDL-1.2

Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
181
e5bc29de3f0a Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents: 55
diff changeset
1 .TH "SDL_GL_SetAttribute" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference"
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
2 .SH "NAME"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
3 SDL_GL_SetAttribute\- Set a special SDL/OpenGL attribute
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
4 .SH "SYNOPSIS"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
5 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
6 \fB#include "SDL\&.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
7 .sp
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
8 \fBint \fBSDL_GL_SetAttribute\fP\fR(\fBSDL_GLattr attr, int value\fR);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
9 .SH "DESCRIPTION"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
10 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
11 Sets the OpenGL \fIattribute\fR \fBattr\fR to \fBvalue\fR\&. The attributes you set don\&'t take effect until after a call to \fI\fBSDL_SetVideoMode\fP\fR\&. You should use \fI\fBSDL_GL_GetAttribute\fP\fR to check the values after a \fBSDL_SetVideoMode\fP call\&.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
12 .SH "RETURN VALUE"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
13 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
14 Returns \fB0\fR on success, or \fB-1\fR on error\&.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
15 .SH "EXAMPLE"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
16 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
17 .nf
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
18 \f(CWSDL_GL_SetAttribute( SDL_GL_RED_SIZE, 5 );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
19 SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 5 );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
20 SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 5 );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
21 SDL_GL_SetAttribute( SDL_GL_DEPTH_SIZE, 16 );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
22 SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
23 if ( (screen=SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL )) == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
24 fprintf(stderr, "Couldn\&'t set GL mode: %s
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
25 ", SDL_GetError());
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
26 SDL_Quit();
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
27 return;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
28 }\fR
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
29 .fi
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
30 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
31 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
32 .RS
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
33 \fBNote:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
34 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
35 The \fBSDL_DOUBLEBUF\fP flag is not required to enable double buffering when setting an OpenGL video mode\&. Double buffering is enabled or disabled using the SDL_GL_DOUBLEBUFFER attribute\&.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
36 .RE
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
37 .SH "SEE ALSO"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
38 .PP
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
39 \fI\fBSDL_GL_GetAttribute\fP\fR, \fIGL Attributes\fR
181
e5bc29de3f0a Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents: 55
diff changeset
40 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01