Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_CreateSemaphore.3 @ 3880:74e828c64315 SDL-1.2
Fixed bug #292
I might be on crack here.
It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and
right channels of a stereo stream together, and clamps the new mono channel if
it would overflow.
Shouldn't it be dividing by 2 to average the two sample points instead of
clamping? Otherwise the mono sample point's volume doubles in the conversion.
This would also make the conversion faster, as it replaces two branches per
sample frame with a bitwise shift.
--ryan.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 24 Sep 2006 15:45:37 +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_CreateSemaphore" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" |
| 0 | 2 .SH "NAME" |
| 3 SDL_CreateSemaphore\- Creates a new semaphore and assigns an initial value to it\&. | |
| 4 .SH "SYNOPSIS" | |
| 5 .PP | |
| 6 \fB#include "SDL\&.h" | |
| 7 #include "SDL_thread\&.h" | |
| 8 .sp | |
| 9 \fBSDL_sem *\fBSDL_CreateSemaphore\fP\fR(\fBUint32 initial_value\fR); | |
| 10 .SH "DESCRIPTION" | |
| 11 .PP | |
| 12 \fBSDL_CreateSemaphore()\fP creates a new semaphore and initializes it with the value \fBinitial_value\fR\&. Each locking operation on the semaphore by \fISDL_SemWait\fR, \fISDL_SemTryWait\fR or \fISDL_SemWaitTimeout\fR will atomically decrement the semaphore value\&. The locking operation will be blocked if the semaphore value is not positive (greater than zero)\&. Each unlock operation by \fISDL_SemPost\fR will atomically increment the semaphore value\&. | |
| 13 .SH "RETURN VALUE" | |
| 14 .PP | |
| 15 Returns a pointer to an initialized semaphore or \fBNULL\fR if there was an error\&. | |
| 16 .SH "EXAMPLES" | |
| 17 .PP | |
| 18 .PP | |
| 19 .nf | |
| 20 \f(CWSDL_sem *my_sem; | |
| 21 | |
| 22 my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE); | |
| 23 | |
| 24 if (my_sem == NULL) { | |
| 25 return CREATE_SEM_FAILED; | |
| 26 }\fR | |
| 27 .fi | |
| 28 .PP | |
| 29 .SH "SEE ALSO" | |
| 30 .PP | |
| 31 \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR | |
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
32 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00 |