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annotate docs/man3/SDL_DisplayFormat.3 @ 2042:3908e1f808e1

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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 15:56:36 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
181
e5bc29de3f0a Updated from the SDL Documentation Project
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1 .TH "SDL_DisplayFormat" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_DisplayFormat\- Convert a surface to the display format
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4 .SH "SYNOPSIS"
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5 .PP
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6 \fB#include "SDL\&.h"
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7 .sp
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8 \fBSDL_Surface *\fBSDL_DisplayFormat\fP\fR(\fBSDL_Surface *surface\fR);
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9 .SH "DESCRIPTION"
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10 .PP
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11 This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer, suitable for fast blitting onto the display surface\&. It calls \fISDL_ConvertSurface\fR
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12 .PP
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13 If you want to take advantage of hardware colorkey or alpha blit acceleration, you should set the colorkey and alpha value before calling this function\&.
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14 .PP
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15 If you want an alpha channel, see \fISDL_DisplayFormatAlpha\fR\&.
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16 .SH "RETURN VALUE"
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17 .PP
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18 If the conversion fails or runs out of memory, it returns \fBNULL\fR
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19 .SH "SEE ALSO"
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20 .PP
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21 \fI\fBSDL_ConvertSurface\fP\fR, \fI\fBSDL_DisplayFormatAlpha\fP\fR \fI\fBSDL_SetAlpha\fP\fR, \fI\fBSDL_SetColorKey\fP\fR, \fI\fBSDL_Surface\fR\fR
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parents: 55
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22 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01