view docs/man3/SDL_Surface.3 @ 4168:69bcba65c388 SDL-1.2

Fixed bug #526 Comment #1 From Simon Howard 2009-03-20 16:50:56 Hi, I'm the author of Chocolate Doom, one of the other source ports that James mentioned. This is a patch against the current SVN version of SDL 1.2 that fixes the bug. It has been tested and hopefully should be obviously correct from examining the changes. I'll give a brief explanation. When the palette is set with SDL_SetPalette, the IDirectDrawPalette_SetEntries DirectX function is invoked. However, when this happens, a WM_PALETTECHANGED message is sent to the window. A WM_PALETTECHANGED message can also be received if the palette is changed for some other reason, like if the system palette is changed. Therefore, the palette change handler (DX5_PaletteChanged) has code to deal with this case. It distinguishes "expected" palette changes (set with SDL_SetPalette) from "unexpected" palette changes using the colorchange_expected variable, which is set before calling IDirectDrawPalette_SetEntries. However, the code to set this variable is missing in the fullscreen code path. By setting this variable, the palette change is handled properly and the freezes go away.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 13 Apr 2009 00:53:12 +0000
parents 4e3b250c950e
children 1238da4a7112
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