view docs/man3/SDL_Surface.3 @ 968:4675910b0b7b

Date: Mon, 11 Oct 2004 15:17:27 +0300 (EEST) From: Hannu Savolainen Subject: Re: SDL uses obsolete OSS features I did some work on getting OSS to work better with SDL. There have been some problems with select which should be fixed now. I'm having some problems in understanding what is the purpose of the DSP_WaitAudio() routine. I added a return to the very beginning of this routine and commendted out the define for USE_BLOCKING_WRITES. At least lbreakout2 seems to work as well as earlier. The latencies are the same. An ordinary blocking write does exactly the same thing than DSP_WaitAudio does. So I would recommend using the USE_BLOCKING_WRITES approach and removing everything from the DSP_WaitAudio routine. Also enabling USE_BLOCKING_WRITES makes it possible to simplify DSP_PlayAudio() because you don't need to handle the partial writes (the do-while loop). Attached is a patch against SDL-1.2.7. After these changes SDL will use OSS as it's designed to be used (make it as simple as possible). This code should work with all OSS implementations because it uses only the very fundamental features that have been there since the jurassic times.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 12 Nov 2004 21:39:04 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_Surface" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_Surface\- Graphical Surface Structure
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef struct SDL_Surface {
        Uint32 flags;                           /* Read-only */
        SDL_PixelFormat *format;                /* Read-only */
        int w, h;                               /* Read-only */
        Uint16 pitch;                           /* Read-only */
        void *pixels;                           /* Read-write */

        /* clipping information */
        SDL_Rect clip_rect;                     /* Read-only */

        /* Reference count -- used when freeing surface */
        int refcount;                           /* Read-mostly */

	/* This structure also contains private fields not shown here */
} SDL_Surface;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBflags\fR
Surface flags
.TP 20
\fBformat\fR
Pixel \fIformat\fR
.TP 20
\fBw, h\fR
Width and height of the surface
.TP 20
\fBpitch\fR
Length of a surface scanline in bytes
.TP 20
\fBpixels\fR
Pointer to the actual pixel data
.TP 20
\fBclip_rect\fR
surface clip \fIrectangle\fR
.SH "DESCRIPTION"
.PP
\fBSDL_Surface\fR\&'s represent areas of "graphical" memory, memory that can be drawn to\&. The video framebuffer is returned as a \fBSDL_Surface\fR by \fI\fBSDL_SetVideoMode\fP\fR and \fI\fBSDL_GetVideoSurface\fP\fR\&. Most of the fields should be pretty obvious\&. \fBw\fR and \fBh\fR are the width and height of the surface in pixels\&. \fBpixels\fR is a pointer to the actual pixel data, the surface should be \fIlocked\fR before accessing this field\&. The \fBclip_rect\fR field is the clipping rectangle as set by \fI\fBSDL_SetClipRect\fP\fR\&.
.PP
The following are supported in the \fBflags\fR field\&.
.TP 20
\fBSDL_SWSURFACE\fP
Surface is stored in system memory
.TP 20
\fBSDL_HWSURFACE\fP
Surface is stored in video memory
.TP 20
\fBSDL_ASYNCBLIT\fP
Surface uses asynchronous blits if possible
.TP 20
\fBSDL_ANYFORMAT\fP
Allows any pixel-format (Display surface)
.TP 20
\fBSDL_HWPALETTE\fP
Surface has exclusive palette
.TP 20
\fBSDL_DOUBLEBUF\fP
Surface is double buffered (Display surface)
.TP 20
\fBSDL_FULLSCREEN\fP
Surface is full screen (Display Surface)
.TP 20
\fBSDL_OPENGL\fP
Surface has an OpenGL context (Display Surface)
.TP 20
\fBSDL_OPENGLBLIT\fP
Surface supports OpenGL blitting (Display Surface)
.TP 20
\fBSDL_RESIZABLE\fP
Surface is resizable (Display Surface)
.TP 20
\fBSDL_HWACCEL\fP
Surface blit uses hardware acceleration
.TP 20
\fBSDL_SRCCOLORKEY\fP
Surface use colorkey blitting
.TP 20
\fBSDL_RLEACCEL\fP
Colorkey blitting is accelerated with RLE
.TP 20
\fBSDL_SRCALPHA\fP
Surface blit uses alpha blending
.TP 20
\fBSDL_PREALLOC\fP
Surface uses preallocated memory
.SH "SEE ALSO"
.PP
\fI\fBSDL_PixelFormat\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01