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annotate docs/man3/SDL_DisplayFormatAlpha.3 @ 2663:0caed045d01b gsoc2008_audio_resampling

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General cleanup and fixed a buffer overrun bug. It may be necessary to normalize filter gain differently or something.
author Aaron Wishnick <schnarf@gmail.com>
date Tue, 12 Aug 2008 00:24:42 +0000
parents 546f7c1eb755
children 1238da4a7112
rev   line source
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e5bc29de3f0a Updated from the SDL Documentation Project
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1 .TH "SDL_DisplayFormatAlpha" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_DisplayFormatAlpha \- 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_DisplayFormatAlpha\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 plus an alpha channel, 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 This function can be used to convert a colourkey to an alpha channel, if the \fBSDL_SRCCOLORKEY\fP flag is set on the surface\&. The generated surface will then be transparent (alpha=0) where the pixels match the colourkey, and opaque (alpha=255) elsewhere\&.
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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 \fISDL_ConvertSurface\fR, \fISDL_SetAlpha\fR, \fISDL_SetColorKey\fR, \fISDL_DisplayFormat\fR, \fISDL_Surface\fR
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22 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01