Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_LockSurface.3 @ 4085:51486c979189 SDL-1.2
> Hi Ryan,
> I checked the list you linked to, but did not see any reference to whether
> the Win32 window centering bug was fixed... Has that been addressed at all?
> I refer to the bug where, unless one has globally set the
> SDL_WINDOW_CENTERED variable in the OS, only the 1st window that is created
> will be centered. Subsequent calls to SetVideoMode will create a window tha
t
> shares the same upper-left corner location.
I'm working on that now, thanks for reporting it. What I'm doing is if the
width and height are the same, I'm leaving the window position alone, but if
they're different they will respect the positioning environment variables.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Fri, 20 Jul 2007 03:25:40 +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_LockSurface" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
| 0 | 2 .SH "NAME" |
| 3 SDL_LockSurface\- Lock a surface for directly access\&. | |
| 4 .SH "SYNOPSIS" | |
| 5 .PP | |
| 6 \fB#include "SDL\&.h" | |
| 7 .sp | |
| 8 \fBint \fBSDL_LockSurface\fP\fR(\fBSDL_Surface *surface\fR); | |
| 9 .SH "DESCRIPTION" | |
| 10 .PP | |
| 11 \fBSDL_LockSurface\fP sets up a surface for directly accessing the pixels\&. Between calls to \fBSDL_LockSurface\fP and \fBSDL_UnlockSurface\fP, you can write to and read from \fBsurface->\fBpixels\fR\fR, using the pixel format stored in \fBsurface->\fBformat\fR\fR\&. Once you are done accessing the surface, you should use \fBSDL_UnlockSurface\fP to release it\&. | |
| 12 .PP | |
| 13 Not all surfaces require locking\&. If \fBSDL_MUSTLOCK\fP(\fBsurface\fR) evaluates to \fB0\fR, then you can read and write to the surface at any time, and the pixel format of the surface will not change\&. | |
| 14 .PP | |
| 15 No operating system or library calls should be made between lock/unlock pairs, as critical system locks may be held during this time\&. | |
| 16 .PP | |
| 17 It should be noted, that since SDL 1\&.1\&.8 surface locks are recursive\&. This means that you can lock a surface multiple times, but each lock must have a match unlock\&. | |
| 18 .PP | |
| 19 .nf | |
| 20 \f(CW \&. | |
| 21 \&. | |
| 22 SDL_LockSurface( surface ); | |
| 23 \&. | |
| 24 /* Surface is locked */ | |
| 25 /* Direct pixel access on surface here */ | |
| 26 \&. | |
| 27 SDL_LockSurface( surface ); | |
| 28 \&. | |
| 29 /* More direct pixel access on surface */ | |
| 30 \&. | |
| 31 SDL_UnlockSurface( surface ); | |
| 32 /* Surface is still locked */ | |
| 33 /* Note: Is versions < 1\&.1\&.8, the surface would have been */ | |
| 34 /* no longer locked at this stage */ | |
| 35 \&. | |
| 36 SDL_UnlockSurface( surface ); | |
| 37 /* Surface is now unlocked */ | |
| 38 \&. | |
| 39 \&.\fR | |
| 40 .fi | |
| 41 .PP | |
| 42 .SH "RETURN VALUE" | |
| 43 .PP | |
| 44 \fBSDL_LockSurface\fP returns \fB0\fR, or \fB-1\fR if the surface couldn\&'t be locked\&. | |
| 45 .SH "SEE ALSO" | |
| 46 .PP | |
| 47 \fI\fBSDL_UnlockSurface\fP\fR | |
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
48 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |