view docs/html/sdlpushevent.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_PushEvent</H1
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>Name</H2
>SDL_PushEvent&nbsp;--&nbsp;Pushes an event onto the event queue</DIV
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>#include "SDL.h"</PRE
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><CODE
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>int <B
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>SDL_PushEvent</B
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>(SDL_Event *event);</CODE
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><H2
>Description</H2
><P
>The event queue can actually be used as a two way communication channel. Not only can events be read from the queue, but the user can also push their own events onto it. <TT
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><I
>event</I
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> is a pointer to the event structure you wish to push onto the queue.</P
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>Note: </B
>Pushing device input events onto the queue doesn't modify the state of the device within SDL.</P
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>Return Value</H2
><P
>Returns <SPAN
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> on success or <SPAN
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>-1</SPAN
> if the event couldn't be pushed.</P
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>See <A
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