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annotate docs/man3/SDL_DisplayFormatAlpha.3 @ 2844:70b63882d2ef

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The YCbCr texture extension works now that bytes_per_pixel() returns the correct value for YUV textures. Yay! I'm still cheering for Ryan's pixel shader instead, since once it works different shaders can handle all the YUV formats.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 06 Dec 2008 18:37:06 +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