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Adam Strzelecki to SDL Since current DirectFB implementation is incomplete for YUV surfaces (actually causes segmentation faults when trying Lock and use YUV planar textures) I decided to fix it a bit. Here's a patch that should make DirectFB properly support YUV both packed and planar (3 planes). (1) Removed SDL_BYTESPERPIXEL at all in favor of DFB_BYTES_PER_PIXEL(SDLToDFBPixelFormat(fmt)) which does return always proper BPP for YUVs too, coz SDL_BYTESPERPIXEL returns incorrect values for FOURCCs (2) Fixed data->pixels allocation for planar YUVs in CreateTexture, it should allocate 150% more space (3) Copy other planes for planar YUVs in UpdateTexture (4) Moved checking if format is supported at all with DirectFB on CreateTexture at the beginning of the code Waiting for comments, -- Adam Strzelecki | nanoant.com
author Sam Lantinga <slouken@libsdl.org>
date Sun, 04 Oct 2009 04:03:37 +0000
parents 355632dca928
children
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>SDL_SetGammaRamp</TITLE
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><H1
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>SDL_SetGammaRamp</H1
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><H2
>Name</H2
>SDL_SetGammaRamp&nbsp;--&nbsp;Sets the color gamma lookup tables for the display</DIV
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>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetGammaRamp</B
></CODE
>(Uint16 *redtable, Uint16 *greentable, Uint16 *bluetable);</CODE
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>Description</H2
><P
>Sets the gamma lookup tables for the display for each color component.
Each table is an array of 256 Uint16 values, representing a mapping
between the input and output for that channel. The input is the index
into the array, and the output is the 16-bit gamma value at that index,
scaled to the output color precision. You may pass NULL to any of the
channels to leave them unchanged.</P
><P
>This function adjusts the gamma based on lookup tables, you can also
have the gamma calculated based on a "gamma function" parameter with
<A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>.</P
><P
>Not all display hardware is able to change gamma.</P
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><H2
>Return Value</H2
><P
>Returns -1 on error (or if gamma adjustment is not supported).</P
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><H2
>See Also</H2
><P
><A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>
<A
HREF="sdlgetgammaramp.html"
>SDL_GetGammaRamp</A
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