view docs/html/sdlgetkeystate.html @ 968:4675910b0b7b

Date: Mon, 11 Oct 2004 15:17:27 +0300 (EEST) From: Hannu Savolainen Subject: Re: SDL uses obsolete OSS features I did some work on getting OSS to work better with SDL. There have been some problems with select which should be fixed now. I'm having some problems in understanding what is the purpose of the DSP_WaitAudio() routine. I added a return to the very beginning of this routine and commendted out the define for USE_BLOCKING_WRITES. At least lbreakout2 seems to work as well as earlier. The latencies are the same. An ordinary blocking write does exactly the same thing than DSP_WaitAudio does. So I would recommend using the USE_BLOCKING_WRITES approach and removing everything from the DSP_WaitAudio routine. Also enabling USE_BLOCKING_WRITES makes it possible to simplify DSP_PlayAudio() because you don't need to handle the partial writes (the do-while loop). Attached is a patch against SDL-1.2.7. After these changes SDL will use OSS as it's designed to be used (make it as simple as possible). This code should work with all OSS implementations because it uses only the very fundamental features that have been there since the jurassic times.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 12 Nov 2004 21:39:04 +0000
parents 355632dca928
children
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>SDL_GetKeyState</H1
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><H2
>Name</H2
>SDL_GetKeyState&nbsp;--&nbsp;Get a snapshot of the current keyboard state</DIV
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>Synopsis</H2
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><PRE
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>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint8 *<B
CLASS="FSFUNC"
>SDL_GetKeyState</B
></CODE
>(int *numkeys);</CODE
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><H2
>Description</H2
><P
>Gets a snapshot of the current keyboard state. The current state is return as a pointer to an array, the size of this array is stored in <TT
CLASS="PARAMETER"
><I
>numkeys</I
></TT
>. The array is indexed by the <A
HREF="sdlkey.html"
><TT
CLASS="LITERAL"
>SDLK_*</TT
></A
> symbols. A value of 1 means the key is pressed and a value of 0 means its not. The pointer returned is a pointer to an internal SDL array and should not be freed by the caller.</P
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>Use <A
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>SDL_PumpEvents</TT
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> to update the state array.</P
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>Uint8 *keystate = SDL_GetKeyState(NULL);
if ( keystate[SDLK_RETURN] ) printf("Return Key Pressed.\n");</PRE
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>SDL Key Symbols</TT
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