Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_CDOpen.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_CDOpen" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference" |
0 | 2 .SH "NAME" |
3 SDL_CDOpen\- Opens a CD-ROM drive for access\&. | |
4 .SH "SYNOPSIS" | |
5 .PP | |
6 \fB#include "SDL\&.h" | |
7 .sp | |
8 \fBSDL_CD *\fBSDL_CDOpen\fP\fR(\fBint drive\fR); | |
9 .SH "DESCRIPTION" | |
10 .PP | |
11 Opens a CD-ROM drive for access\&. It returns a \fI\fBSDL_CD\fR\fR structure on success, or \fBNULL\fP if the drive was invalid or busy\&. This newly opened CD-ROM becomes the default CD used when other CD functions are passed a \fBNULL\fP CD-ROM handle\&. | |
12 .PP | |
13 Drives are numbered starting with 0\&. Drive 0 is the system default CD-ROM\&. | |
14 .SH "EXAMPLES" | |
15 .PP | |
16 .nf | |
17 \f(CWSDL_CD *cdrom; | |
18 int cur_track; | |
19 int min, sec, frame; | |
20 SDL_Init(SDL_INIT_CDROM); | |
21 atexit(SDL_Quit); | |
22 | |
23 /* Check for CD drives */ | |
24 if(!SDL_CDNumDrives()){ | |
25 /* None found */ | |
26 fprintf(stderr, "No CDROM devices available | |
27 "); | |
28 exit(-1); | |
29 } | |
30 | |
31 /* Open the default drive */ | |
32 cdrom=SDL_CDOpen(0); | |
33 | |
34 /* Did if open? Check if cdrom is NULL */ | |
35 if(!cdrom){ | |
36 fprintf(stderr, "Couldn\&'t open drive: %s | |
37 ", SDL_GetError()); | |
38 exit(-1); | |
39 } | |
40 | |
41 /* Print Volume info */ | |
42 printf("Name: %s | |
43 ", SDL_CDName(0)); | |
44 printf("Tracks: %d | |
45 ", cdrom->numtracks); | |
46 for(cur_track=0;cur_track < cdrom->numtracks; cur_track++){ | |
47 FRAMES_TO_MSF(cdrom->track[cur_track]\&.length, &min, &sec, &frame); | |
48 printf(" Track %d: Length %d:%d | |
49 ", cur_track, min, sec); | |
50 } | |
51 | |
52 SDL_CDClose(cdrom);\fR | |
53 .fi | |
54 .PP | |
55 .SH "SEE ALSO" | |
56 .PP | |
57 \fI\fBSDL_CD\fR\fR, \fI\fBSDL_CDtrack\fR\fR, \fI\fBSDL_CDClose\fP\fR | |
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
58 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58 |