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Date: Fri, 19 Dec 2008 20:17:35 +0100 From: Couriersud Subject: Re: Aw: Experience using SDL1.3 in sdlmame/Proposal for api additions > For consistency you'd probably want: > SDL_SetRenderDrawColor(Uint8 r, Uint8 g, Uint8 b, Uint8 a); > SDL_SetRenderDrawBlendMode(SDL_BlendMode blendMode); > SDL_RenderLine(int x1, int y1, int x2, int y2); > SDL_RenderFill(SDL_Rect *rect); > > You probably also want to add API functions query the current state. > I have implemented the above api for the opengl, x11, directfb and software renderers. I have also renamed *TEXTUREBLENDMODE* constants to BLENDMODE*. The unix build compiles. The windows renderer still needs to be updated, but I have no windows development machine at hand. Have a look at the x11 renderer for a sample. Vector games now run at 90% both on opengl and directfb in comparison to sdlmame's own opengl renderer. The same applies to raster games. The diff also includes a) Changed XDrawRect to XFillRect in x11 renderer b) A number of changes to fix blending and modulation issues in the directfb renderer.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 20 Dec 2008 12:00:00 +0000
parents 546f7c1eb755
children 1238da4a7112
line wrap: on
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.TH "SDL_SemTryWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SemTryWait \- Attempt to lock a semaphore but don\&'t suspend the thread\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBint \fBSDL_SemTryWait\fP\fR(\fBSDL_sem *sem\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_SemTryWait\fP is a non-blocking varient of \fI\fBSDL_SemWait\fP\fR\&. If the value of the semaphore pointed to by \fBsem\fR is positive it will atomically decrement the semaphore value and return 0, otherwise it will return \fBSDL_MUTEX_TIMEOUT\fR instead of suspending the thread\&.
.PP
After \fBSDL_SemTryWait\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
.SH "RETURN VALUE"
.PP
Returns \fB0\fR if the semaphore was successfully locked or either \fBSDL_MUTEX_TIMEOUT\fR or \fB-1\fR if the thread would have suspended or there was an error, respectivly\&.
.PP
If the semaphore was not successfully locked, the semaphore will be unchanged\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWres = SDL_SemTryWait(my_sem);

if (res == SDL_MUTEX_TIMEOUT) {
        return TRY_AGAIN;
}
if (res == -1) {
        return WAIT_ERROR;
}

\&.\&.\&.

SDL_SemPost(my_sem);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00