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[PATCH] SDL_GetVideoMode() does not find best mode, part 2 Following commit 1.51, I come accross a problem when SDL must choose between several video modes that could suit the one asked. If I ask 320x240 with this list: 768x480 768x240 640x400 640x200 384x480 384x240 320x400 320x200 The smallest selectables modes are 384x240 and 320x400. And SDL choose the later in this list, but 384x240 is more suitable. So I added a check to compare the pixel count (surface) of modes, and select the one which has the smallest pixel count. In my example, 384x240 has 92160 pixels, and 320x400 has 128000 pixels. So now SDL will choose 384x240 for the asked 320x240 mode.
author Patrice Mandin <patmandin@gmail.com>
date Thu, 19 Jan 2006 21:28:52 +0000
parents 355632dca928
children
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<HTML
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>SDL_MapRGBA</TITLE
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><H1
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>SDL_MapRGBA</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1687"
></A
><H2
>Name</H2
>SDL_MapRGBA&nbsp;--&nbsp;Map a RGBA color value to a pixel format.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1690"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN1691"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_MapRGBA</B
></CODE
>(SDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b, Uint8 a);</CODE
></P
><P
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></DIV
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><DIV
CLASS="REFSECT1"
><A
NAME="AEN1697"
></A
><H2
>Description</H2
><P
>Maps the RGBA color value to the specified pixel format and returns the
pixel value as a 32-bit int.</P
><P
>If the format has a palette (8-bit) the index of the closest matching
color in the palette will be returned.</P
><P
>If the specified pixel format has no alpha component the alpha value
will be ignored (as it will be in formats with a palette).</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1702"
></A
><H2
>Return Value</H2
><P
>A pixel value best approximating the given RGBA color value for a given
pixel format. If the pixel format bpp (color depth) is less than 32-bpp
then the unused upper bits of the return value can safely be ignored
(e.g., with a 16-bpp format the return value can be assigned to a
<SPAN
CLASS="TYPE"
>Uint16</SPAN
>, and similarly a <SPAN
CLASS="TYPE"
>Uint8</SPAN
> for an 8-bpp
format).</P
></DIV
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><A
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlgetrgb.html"
>SDL_GetRGB</A
>,
<A
HREF="sdlgetrgba.html"
>SDL_GetRGBA</A
>,
<A
HREF="sdlmaprgb.html"
>SDL_MapRGB</A
>,
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HREF="sdlpixelformat.html"
>SDL_PixelFormat</A
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