To: sdl@libsdl.org From: Christian Walther <cwalther@gmx.ch> Date: Thu, 15 Dec 2005 21:19:53 +0100 Subject: [SDL] More mouse enhancements for Mac OS X The attached patch brings two more enhancements to mouse handling on Mac OS X (Quartz): 1. Currently, after launching an SDL application, SDL's notion of the mouse position is stuck in the top left corner (0,0) until the first time the mouse is moved. That's because the UpdateMouse() function isn't implemented in the Quartz driver. This patch adds it. 2. When grabbing input while the mouse cursor is hidden, the function CGAssociateMouseAndMouseCursorPosition(0) is called, which prevents the system's notion of the mouse location from moving (and therefore leaving the SDL window) even when the mouse is moved. However, apparently the Wacom tablet driver (and maybe other special pointing device drivers) doesn't care about that setting and still allows the mouse location to go outside of the window. Interestingly, the system cursor, which is made visible by the existing code in SDL in that case, does not follow the mouse location, but appears in the middle of the SDL window. The mouse location being outside of the window however means that mouse button events go to background applications (or the dock or whatever is there), which is very confusing to the user who sees no cursor outside of the SDL window. I have not found any way of intercepting these events (and that's probably by design, as "normal" applications shouldn't prevent the user from bringing other applications' windows to the front by clicking on them). An idea would be placing a fully transparent, screen-filling window in front of everything, but I fear that this might affect rendering performance (by doing unnecessary compositing, using up memory, or whatever). The deluxe solution to the problem would be talking to the tablet driver using AppleEvents to tell it to constrain its mapped area to the window (see Wacom's "TabletEventDemo" sample app, http://www.wacomeng.com/devsupport/mac/downloads.html), but I think that the bloat that solution would add to SDL would outweigh its usefulness. What I did instead in my patch is reassociating mouse and cursor when the mouse leaves the window while an invisible grab is in effect, and restoring the grab when the window is entered. That way, the grab can still be effectively broken by a tablet, but at least it's obvious to the user that it is broken. That change is minimal - it doesn't affect operation with a mouse (or a trackpad), and the code that it adds is not executed on every PumpEvents() call, only when entering and leaving the window. Unless there are any concerns about the patch, please apply. Feel free to shorten the lengthy comment in SDL_QuartzEvents.m if you think it's too verbose. Thanks -Christian

This is the porting of 1.2.0 version of SDL (the latest stable one)
to AmigaOS/68k.

All the bugs known of the past version have been corrected. And I've
added all the new SDL features.

This version of SDL needs Cybergraphx V3 (r69+) or CyberGraphX V4
and AHI v3+. Probably it works also with P96 or CGXAga, but it's 
untested.

This version is available as linked library for SAS/C and GCC, only 68k this 
time, a powerup (ppcemu compatible) and a morphos version will be ready quite 
soon (i hope).

Implemented:

- 8/16/24/32bit video modes, both fullscreen and windowed.
- Hardware surfaces.
- CGX blitting acceleration.
- CGX colorkey blitting acceleration.
- AHI audio (8/16 bit, with any audio format), always uses unit 0 for now.
- Thread support (maybe not 100% compatible with other implementations)
- Semaphores 
- Window resizing and backdrop windows (NEW)
- Joystick/Joypad support.

To do:

- CDRom audio playing support
- OpenGL (A guy was working on it but I've lost his tracks :( )

The SAS/C library is distributed with debug info attached, to strip debug info 
simply add STRIPDEBUG argument to the linker.

NOTE: SDL includes debug output using kprintf, to disable it add to your 
project a function like this:

void kprintf(char *a,...)
{
}

Otherwise you can redirect the debug to a console window with sushi, sashimi or
similar tools (the default output is the internal serial port). 

For info, support, bugfix and other feel free to mail me:

Gabriele Greco (gabriele.greco@aruba.it)

You can find also a small SDL Amiga page at:
http://ggreco.interfree.it/sdl.html