Mercurial > sdl-ios-xcode
view docs/man3/SDL_JoyBallEvent.3 @ 4392:2b8c1aea633b SDL-1.2
Fixed bug #898
Jeremiah Morris 2009-12-09 16:07:17 PST
No-op GlobalToLocal translations in fullscreen mode
On my MacBook Pro running 10.6, I noticed a small upward bias on mouse movement
in a fullscreen SDL application. The app uses WarpCursor and GetMouseState in a
loop to measure relative movement. I tracked it down to NSWindow's
convertBaseToScreen: routine, which added a 2-pixel offset on the Y coordinate
instead of the expected (+0,+0) translation.
In fullscreen mode, QZ_PrivateWarpCursor() does not translate the desired
position through QZ_PrivateGlobalToLocal() before passing it to the Core
Graphics system. However, QZ_GetMouseLocation() does call the reverse
QZ_PrivateLocalToGlobal() even in fullscreen mode. This asymmetry caused
problems each time the mouse was moved.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 11 Dec 2009 15:31:37 +0000 |
parents | 1238da4a7112 |
children |
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.TH "SDL_JoyBallEvent" "3" "Tue 11 Sep 2001, 22:59" "SDL" "SDL API Reference" .SH "NAME" SDL_JoyBallEvent \- Joystick trackball motion event structure .SH "STRUCTURE DEFINITION" .PP .nf \f(CWtypedef struct{ Uint8 type; Uint8 which; Uint8 ball; Sint16 xrel, yrel; } SDL_JoyBallEvent;\fR .fi .PP .SH "STRUCTURE DATA" .TP 20 \fBtype\fR \fBSDL_JOYBALLMOTION\fP .TP 20 \fBwhich\fR Joystick device index .TP 20 \fBball\fR Joystick trackball index .TP 20 \fBxrel\fR, \fByrel\fR The relative motion in the X/Y direction .SH "DESCRIPTION" .PP \fBSDL_JoyBallEvent\fR is a member of the \fI\fBSDL_Event\fR\fR union and is used when an event of type \fBSDL_JOYBALLMOTION\fP is reported\&. .PP A \fBSDL_JOYBALLMOTION\fP event occurs when a user moves a trackball on the joystick\&. The field \fBwhich\fR is the index of the joystick that reported the event and \fBball\fR is the index of the trackball (for a more detailed explaination see the \fIJoystick section\fR)\&. Trackballs only return relative motion, this is the change in position on the ball since it was last polled (last cycle of the event loop) and it is stored in \fBxrel\fR and \fByrel\fR\&. .SH "SEE ALSO" .PP \fI\fBSDL_Event\fR\fR, \fIJoystick Functions\fR, \fI\fBSDL_JoystickEventState\fP\fR, \fI\fBSDL_JoystickGetBall\fP\fR .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:59