sdl_setvideomode.3

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.TH "SDL_SetVideoMode" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SetVideoMode\- Set up a video mode with the specified width, height and bits-per-pixel\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBSDL_Surface *\fBSDL_SetVideoMode\fP\fR(\fBint width, int height, int bpp, Uint32 flags\fR);
.SH "DESCRIPTION"
.PP
Set up a video mode with the specified width, height and bits-per-pixel\&.
.PP
If \fBbpp\fR is 0, it is treated as the current display bits per pixel\&.
.PP
The \fBflags\fR parameter is the same as the \fBflags\fR field of the \fI\fBSDL_Surface\fR\fR structure\&. OR\&'d combinations of the following values are valid\&.
.TP 20
\fBSDL_SWSURFACE\fP
Create the video surface in system memory
.TP 20
\fBSDL_HWSURFACE\fP
Create the video surface in video memory
.TP 20
\fBSDL_ASYNCBLIT\fP
Enables the use of asynchronous updates of the display surface\&. This will usually slow down blitting on single CPU machines, but may provide a speed increase on SMP systems\&.
.TP 20
\fBSDL_ANYFORMAT\fP
Normally, if a video surface of the requested bits-per-pixel (\fBbpp\fR) is not available, SDL will emulate one with a shadow surface\&. Passing \fBSDL_ANYFORMAT\fP prevents this and causes SDL to use the video surface, regardless of its pixel depth\&.
.TP 20
\fBSDL_HWPALETTE\fP
Give SDL exclusive palette access\&. Without this flag you may not always get the the colors you request with \fI\fBSDL_SetColors\fP\fR or \fI\fBSDL_SetPalette\fP\fR\&.
.TP 20
\fBSDL_DOUBLEBUF\fP
Enable hardware double buffering; only valid with SDL_HWSURFACE\&. Calling \fI\fBSDL_Flip\fP\fR will flip the buffers and update the screen\&. All drawing will take place on the surface that is not displayed at the moment\&. If double buffering could not be enabled then \fBSDL_Flip\fP will just perform a \fI\fBSDL_UpdateRect\fP\fR on the entire screen\&.
.TP 20
\fBSDL_FULLSCREEN\fP
SDL will attempt to use a fullscreen mode\&. If a hardware resolution change is not possible (for whatever reason), the next higher resolution will be used and the display window centered on a black background\&.
.TP 20
\fBSDL_OPENGL\fP
Create an OpenGL rendering context\&. You should have previously set OpenGL video attributes with \fI\fBSDL_GL_SetAttribute\fP\fR\&.
.TP 20
\fBSDL_OPENGLBLIT\fP
Create an OpenGL rendering context, like above, but allow normal blitting operations\&. The screen (2D) surface may have an alpha channel, and \fI\fBSDL_UpdateRects\fP\fR must be used for updating changes to the screen surface\&.
.TP 20
\fBSDL_RESIZABLE\fP
Create a resizable window\&. When the window is resized by the user a \fI\fBSDL_VIDEORESIZE\fP\fR event is generated and \fBSDL_SetVideoMode\fP can be called again with the new size\&.
.TP 20
\fBSDL_NOFRAME\fP
If possible, \fBSDL_NOFRAME\fP causes SDL to create a window with no title bar or frame decoration\&. Fullscreen modes automatically have this flag set\&.
.PP
.RS
\fBNote:  
.PP
Whatever \fBflags\fR \fBSDL_SetVideoMode\fP could satisfy are set in the \fBflags\fR member of the returned surface\&.
.RE
.PP
.RS
\fBNote:  
.PP
The \fBbpp\fR parameter is the number of bits per pixel, so a \fBbpp\fR of 24 uses the packed representation of 3 bytes/pixel\&. For the more common 4 bytes/pixel mode, use a \fBbpp\fR of 32\&. Somewhat oddly, both 15 and 16 will request a 2 bytes/pixel mode, but different pixel formats\&.
.RE
.SH "RETURN VALUE"
.PP
The framebuffer surface, or \fBNULL\fR if it fails\&. The surface returned is freed by SDL_Quit() and should nt be freed by the caller\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_LockSurface\fP\fR, \fI\fBSDL_SetColors\fP\fR, \fI\fBSDL_Flip\fP\fR, \fI\fBSDL_Surface\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01