Mercurial > sdl-ios-xcode
view docs/man3/SDL_DisplayFormatAlpha.3 @ 4223:63fd67e17705 SDL-1.2
Fixed bug #727
Lorenzo Desole 2009-04-19 07:36:10 PDT
I am one of the developers of a multimedia application (My Media System MMS),
which uses SDL.
MMS is normally running in fullscreen mode but it switches it off before
launching external applications (mplayer, xine, etc.).
The problem with fullscreen is that when the latter is switched off either via
SDL_WM_ToggleFullScreen() or SDL_SetVideoMode(), SDL compares the current
screen sizes with the ones saved when the video system was initted, and if they
don't match, it calls XF86VidModeSwitchToMode() to switch to the old modeline.
This makes it impossible for external programs and for MMS itself to use RandR
to change the screen size, because next time fullscreen mode is turned off, it
bombs out with the following error:
X Error of failed request: BadValue (integer parameter out of range for
operation)
Major opcode of failed request: 136 (XFree86-VidModeExtension)
Minor opcode of failed request: 10 (XF86VidModeSwitchToMode)
[...]
Obviously this happens only if the new screen resolution is smaller than the
original one and XF86VidModeSwitchToMode() can't succeed.
I couldn't find any way to inform SDL that the screen resolution it uses as
reference is no longer valid.
This can be fixed by adding "save_mode(this)" to
./src/video/x11/SDL_x11modes.c, API X11_EnterFullScreen(_THIS), like this:
int X11_EnterFullScreen(_THIS)
{
int okay;
+ save_mode(this);
I can't rule out possible side effects, but I don't see any.
While I admit this is a minor issue for the general users, it is a major
showstopper for our program where the ability to change screen resolution and
refresh rate according to the movie being played, is very important.
Thanks in advance.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 21 Sep 2009 11:14:36 +0000 |
parents | 4e3b250c950e |
children | 1238da4a7112 |
line wrap: on
line source
.TH "SDL_DisplayFormatAlpha" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_DisplayFormatAlpha \- Convert a surface to the display format .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBSDL_Surface *\fBSDL_DisplayFormatAlpha\fP\fR(\fBSDL_Surface *surface\fR); .SH "DESCRIPTION" .PP This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer plus an alpha channel, suitable for fast blitting onto the display surface\&. It calls \fISDL_ConvertSurface\fR .PP If you want to take advantage of hardware colorkey or alpha blit acceleration, you should set the colorkey and alpha value before calling this function\&. .PP This function can be used to convert a colourkey to an alpha channel, if the \fBSDL_SRCCOLORKEY\fP flag is set on the surface\&. The generated surface will then be transparent (alpha=0) where the pixels match the colourkey, and opaque (alpha=255) elsewhere\&. .SH "RETURN VALUE" .PP If the conversion fails or runs out of memory, it returns \fBNULL\fR .SH "SEE ALSO" .PP \fISDL_ConvertSurface\fR, \fISDL_SetAlpha\fR, \fISDL_SetColorKey\fR, \fISDL_DisplayFormat\fR, \fISDL_Surface\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01