Path: utzoo!attcan!uunet!husc6!cmcl2!nrl-cmf!ames!pasteur!cory.Berkeley.EDU!soohoo
From: soohoo@cory.Berkeley.EDU (Ken Soohoo)
Newsgroups: comp.sys.atari.st
Subject: Re: button events.  Wanting to wait for either one or two clicks.
Keywords: evnt_button, evnt_multi, Laser C
Message-ID: <7632@pasteur.Berkeley.EDU>
Date: 21 Nov 88 15:56:31 GMT
References: <1988Nov19.180454.563@gpu.utcs.toronto.edu>
Sender: news@pasteur.Berkeley.EDU
Reply-To: soohoo@cory.Berkeley.EDU.UUCP (Ken Soohoo)
Organization: University of California, Berkeley
Lines: 71

In article <1988Nov19.180454.563@gpu.utcs.toronto.edu> romwa@gpu.utcs.toronto.edu (Mark Dornfeld) writes:
>
>When using the GEM event manager, is there a way of setting up
>an event which involves clicking one OR two buttons?  I
>am thinking of a case like the desktop, where one can select a
>disk by clicking once and get a directory by double-clicking.
>
>
>Pavneet Arora
>...!utgpu!rom!pavneet

1) If you want to wait for a double click, the second parameter in
evnt_multi() controls the # of clicks you wait for, likewise the
first parameter in evnt_button().

2) If you want to sense two click on _different_ buttons, you're going
to have to go to a little work:
 	
	The problem is that the evnt_multi() evnt_button() routines
	just don't return anything other than the left button being
	clicked (although you _can_ properly sense a right click with
	graf_mkstate() and vq_mouse(), and I'd use graf_mkstate() with
	other 'desktop' routines like evnt_ calls).

	But you really want that right button click?
	Install your own 68000 Assembly routine as the button event
	handler, it's _not_ hard!
	
	The button value comes in d0, save it out to a nice place,
	and then change it to a left click no matter what, and install
	the routine using vex_butv();

	vex_butv(handle, new_function, old_function);
	int handle;
	void (*new_function), (*old_function);

		globl	_NEW_BUT,_BUT_ADDR,_BUT_STATE

*	The true button state is saved  and the Left button
*	flag is passed back to the AES mouse button interrupt routine. 
*
*  in:
*	_BUT_ADDR contains the address of the AES interrupt routine
*	that deals with mouse buttons.
*
* out:
*	_BUT_STATE contains the actual mouse button state prior to testing
*	to be read by the calling program.


_NEW_BUT:	tst	d0
		beq	place
		move.w	d0,_BUT_STATE
		move.w	#1,d0			; always return left button
place:		move.l	_BUT_ADDR,-(sp)
		rts				; jmp to AES subroutine

_BUT_ADDR:	ds.l	1
_BUT_STATE:	ds.w	1


In the above case, vex_butv(handle, NEW_BUT, &BUT_ADDR); to get into
the new routine, and vex_butv(handle, BUT_ADDR, &dummy); to get out.

Notable useful additions: another location to sense if the button was
an "up" or a "down".

--Kenneth Soohoo	(soohoo@cory.Berkeley.Edu)
  Atari 400/800/600xl/800xl/1200/130xe/65xe, 1040ST hacker
  Sometime Berkeley Student, othertimes...
  My opinions are my OWN, not necessarily Atari's