view docs/html/sdlgetkeystate.html @ 1544:ab1e4c41ab71

Fixed bug #33 Mike Frysinger wrote: > with libsdl-1.2.9, some games (like bomberclone) started > segfaulting in Gentoo [...snip...] > the last change in the last hunk: [...snip...] > if i change the statement to read: > (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures() > bomberclone no longer segfaults on my box Alex Volkov wrote: > The test "(table[which].blit_features & GetBlitFeatures()) == > table[which].blit_features)" is correct, and the previous > "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken. I think there is potentially a slightly different cause of the above problem. During the introduction of the Altivec code, the blit_table struct field 'alpha' got changed from a straightforward enum to a bitmask, which makes perfect sense by itself. However, now the table driven blitter selection code in SDL_CalculateBlitN() can choose the wrong blitters when searching for a NO_ALPHA blitter because of the following code: int a_need = 0; ... (a_need & table[which].alpha) == a_need && When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing alpha channel bits to appear in a non-alpha destination surface. I suppose this could theoretically be an indirect cause of the segfault mentioned above. I *think* this can be fixed by changing to int a_need = NO_ALPHA;
author Sam Lantinga <slouken@libsdl.org>
date Wed, 15 Mar 2006 15:47:49 +0000
parents 355632dca928
children
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>SDL_GetKeyState</H1
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>Name</H2
>SDL_GetKeyState&nbsp;--&nbsp;Get a snapshot of the current keyboard state</DIV
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>#include "SDL.h"</PRE
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>Uint8 *<B
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>SDL_GetKeyState</B
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>(int *numkeys);</CODE
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>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
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>numkeys</I
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>. The array is indexed by the <A
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> 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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> 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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