9D. intuition support functions
-------------------------------

	wptr:=OpenW(x,y,width,height,IDCMP,wflags,title,
                    screen,sflags,gadgets,taglist=NIL)

creates a window where wflags are flags for window layout
(like BACKDROP, SIMPLEREFRESH e.d, usually $F) and sflags are
for specifying the type of screen to open on (1=wb,15=custom).
screen must only be valid if sflags=15, else NIL will do.
gadgets may point to a glist structure, which you can easily
create with the Gadget() function, else NIL.

	CloseW(wptr)

closes that screen again. Only difference from CloseWindow()
is that it accepts NIL-pointers and sets stdrast back to NIL.

	sptr:=OpenS(width,height,depth,sflags,title,taglist=NIL)

opens a custom screen for you. depth is number of bitplanes (1-6, 1-8 AGA).

	CloseS(sptr)

as CloseW(), now for screens.

	nextbuffer:=Gadget(buffer,glist,id,flags,x,y,width,string)

[obsolete]
This function creates a list of gadgets, which can then be put in your
window by giving them as an argument to OpenW(), or afterwards with
intuition functions like AddGlist().
buffer is mostly an ARRAY of at least GADGETSIZE bytes to hold all the
structures associated with one gadget, id is any number that may help you
remember which gadget was pressed when an IntuiMessage arrives.
Flags are: 0=normal gadget, 1=boolean gadget, 3=boolean gadget that is
selected. Width is width in pixels, that should be large enough to hold
the string, which will be auto-centered. glist should be NIL for the first
gadget, and glistvar for all others, so E may link all gadgets.
The function returns a pointer to the next buffer (=buffer+GADGETSIZE).
Example for three gadgets:

CONST MAXGADGETS=GADGETSIZE*3

DEF buf[MAXGADGETS]:ARRAY, next, wptr

next:=Gadget(buf,NIL,1,0,10,20,80,'bla')   /* the 1st gadget */
next:=Gadget(next,buf,... )
next:=Gadget(next,buf,... )                /* any amount linked 2 1st */

wptr:=OpenW( ...,buf)

	code:=Mouse()

gives you the current state of all 2 or 3 mouse buttons; left=1,
right=2 and middle=4. If for example code=3 then left and right were
pressed together.
NOTEZ BIEN: this is not a real intuition function, if you want to
know about mouse-events the proper way, you'll have to check the
intuimessages that your window receives. This is the only E
function that directly checks the hardware, and thus only useful
in demo-like programs and for testing. (DO NOT USE THIS FUNCTION
IN PROGRAMS THAT ARE SUPPOSED TO WORK UNDER THE OS)

	bool:=LeftMouse(win)     WaitLeftMouse(win)

intuition Mouse() alternatives for programs that only want to test for
a mouseclick.

	x:=MouseX(win)     y:=MouseY(win)

[obsolete]
enables you to read the mouse coordinates. win is the window
they need to be relative to.

	class:=WaitIMessage(window)

This function makes it easier to just wait for a window event. It simply
waits until a intuimessage arrives, and returns the class of the event.
It stores other variables like code and qualifiers as private global
variables, for access with functions described below.
WaitIMessage() represents the following code:

PROC waitimessage(win:PTR TO window)
  DEF port,mes:PTR TO intuimessage,class,code,qual,iaddr
  port:=win.userport
  IF (mes:=GetMsg(port))=NIL
    REPEAT
      WaitPort(port)
    UNTIL (mes:=GetMsg(port))<>NIL
  ENDIF
  class:=mes.class
  code:=mes.code             /* stored internally */
  qual:=mes.qualifier
  iaddr:=mes.iaddress
  ReplyMsg(mes)
ENDPROC class

as you see, it gets exactly one message, and does not forget about
multiple messages arriving in one event, if called more than once.
For example, say you opened a window that displays something and just
waits for a closegadget (you specified IDCMP_CLOSEWINDOW only):

WaitIMessage(mywindow)

or, you have a program that waits for more types of events, handles
them in a loop, and ends on a closewindow event:

WHILE (class:=WaitIMessage(win))<>IDCMP_CLOSEWINDOW
  /* handle other classes */
ENDWHILE

	code:=MsgCode()    qual:=MsgQualifier()    iaddr:=MsgIaddr()

These all supply you with the private global variables as mentioned
before. the values returned are all defined by the most recent call
to WaitIMessage(). Example:

IF class:=IDCMP_GADGETUP
  mygadget:=MsgIaddr()
  IF mygadget.userdata=1 THEN  /* ... user pressed gadget #1 */
ENDIF