Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_PollEvent.3 @ 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 | e5bc29de3f0a |
children | 546f7c1eb755 |
rev | line source |
---|---|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
1 .TH "SDL_PollEvent" "3" "Tue 11 Sep 2001, 22:59" "SDL" "SDL API Reference" |
0 | 2 .SH "NAME" |
3 SDL_PollEvent\- Polls for currently pending events\&. | |
4 .SH "SYNOPSIS" | |
5 .PP | |
6 \fB#include "SDL\&.h" | |
7 .sp | |
8 \fBint \fBSDL_PollEvent\fP\fR(\fBSDL_Event *event\fR); | |
9 .SH "DESCRIPTION" | |
10 .PP | |
11 Polls for currently pending events, and returns \fB1\fR if there are any pending events, or \fB0\fR if there are none available\&. | |
12 .PP | |
13 If \fBevent\fR is not \fBNULL\fP, the next event is removed from the queue and stored in that area\&. | |
14 .SH "EXAMPLES" | |
15 .PP | |
16 .PP | |
17 .nf | |
18 \f(CWSDL_Event event; /* Event structure */ | |
19 | |
20 \&. | |
21 \&. | |
22 \&. | |
23 /* Check for events */ | |
24 while(SDL_PollEvent(&event)){ /* Loop until there are no events left on the queue */ | |
25 switch(event\&.type){ /* Process the appropiate event type */ | |
26 case SDL_KEYDOWN: /* Handle a KEYDOWN event */ | |
27 printf("Oh! Key press | |
28 "); | |
29 break; | |
30 case SDL_MOUSEMOTION: | |
31 \&. | |
32 \&. | |
33 \&. | |
34 default: /* Report an unhandled event */ | |
35 printf("I don\&'t know what this event is! | |
36 "); | |
37 } | |
38 }\fR | |
39 .fi | |
40 .PP | |
41 .SH "SEE ALSO" | |
42 .PP | |
43 \fI\fBSDL_Event\fR\fR, \fI\fBSDL_WaitEvent\fP\fR, \fI\fBSDL_PeepEvents\fP\fR | |
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
44 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:59 |