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Date: Sat, 14 Feb 2004 14:52:40 +0200 From: "Mike Gorchak" Subject: Batch of the QNX6 fixes for the SDL 1. Updated readme.QNX 2. Fixed crashes during intensive window updating under fast machines (got over 200 rectangles for update). 3. Fixed double-buffered fullscreen modes, now it works as needed. 4. Fixed Photon detection algorithm. 5. Fixed HWSURFACE update function. 6. Added SDL_PHOTON_FULLSCREEN_REFRESH environment variable support for control refresh rates under Photon. 7. Added 640x400 fullscreen mode emulation via 640x480 (if videodriver not supports original 640x400 mode of course) shifted by 40 vertical pixels from begin, to center it. It's needed for some old DOS games which ran in doubled 320x200 mode. 8. Added available video ram amount support. 8. Added hardware surface allocation/deallocation support if current videomode and videodriver supports it. 9. Added hardware filling support. 10. Added hardware blits support (simple and colorkeyed). And I've added to testvidinfo test color-keyed blits benchmark (maybe need to add alpha blits benchmark too ?). Currently Photon not supporting any alpha hardware blittings (all drivers lack of alpha blitting code support, only software alpha blitting exist in photon, which is hundreds times slowest than the SDL's one). So I've not added the alpha support. I suppose new QNX 6.3 will have the hardware alpha support, so when it will be done, I'll add alpha support.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 14 Feb 2004 20:22:21 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_MixAudio</TITLE
><META
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"><LINK
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><H1
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></A
>SDL_MixAudio</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN7107"
></A
><H2
>Name</H2
>SDL_MixAudio&nbsp;--&nbsp;Mix audio data</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN7110"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN7111"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void <B
CLASS="FSFUNC"
>SDL_MixAudio</B
></CODE
>(Uint8 *dst, Uint8 *src, Uint32 len, int volume);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7117"
></A
><H2
>Description</H2
><P
>This function takes two audio buffers of <TT
CLASS="PARAMETER"
><I
>len</I
></TT
> bytes each
of the playing audio format and mixes them, performing addition, volume
adjustment, and overflow clipping. The <TT
CLASS="PARAMETER"
><I
>volume</I
></TT
> ranges
from 0 to <TT
CLASS="LITERAL"
>SDL_MIX_MAXVOLUME</TT
> and should be set to the maximum
value for full audio volume. Note this does not change hardware volume. This is
provided for convenience -- you can mix your own audio data.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>Do not use this function for mixing together more than two streams of sample
data. The output from repeated application of this function may be distorted
by clipping, because there is no accumulator with greater range than the
input (not to mention this being an inefficient way of doing it).
Use mixing functions from SDL_mixer, OpenAL, or write your own mixer instead.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7125"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
></P
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