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From: aaron@stat.tamu.edu (Aaron Hightower)
Newsgroups: comp.sys.amiga.programmer
Subject: How to use BPLCON2?
Message-ID: <12181@helios.TAMU.EDU>
Date: 15 Feb 91 00:22:55 GMT
Sender: usenet@helios.TAMU.EDU
Lines: 24

Today, I was working on one of my programs that uses both sprites and menus
on the same screen.  The problem that I ran into was when I tried to use the
menus.  When the menu is pulled down, the sprite(s) overlap the menu.  I
read in the RKM Hardware manual and found the chapter on how to set the
playfield-sprite priorities, and it mentions that you can use BPLCON2 to
set the priorities.  For a 1-Playfield screen, you are supposed to use
bits 3,4, and 5.  I tried what the manual suggested, but nothing appeared
to change.  The sprites still overlapped my menus.  So how can I do this? 
Can I set some flags in the NewScreen structure or something?  Am I writing
to the wrong place (I am using 0x104 for BPLCON2?)

The other thing that I tried (first) was to read the MENUBUTTON, MENUDOWN
event from my IDCMP port, but since Intuition evidently processes the right
button for the menus, it is not accessible (is absorbed and not passed 
through the IDCMP port.)  It mentioned that you could do a RMBTRAP, but that
this would temporarily disable the menu.

I am sure that this can be done.  I believe that AudioMaster does this,
because they use sprites for their little range thingymadoppers...
Is there a little bit of code that I could insert to do the RMBTRAP, and still
have the menus work normally?

Mucho gracious,
  Aaron Hightower