Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!helios!bcm!dimacs.rutgers.edu!rutgers!cbmvax!jesup
From: jesup@cbmvax.commodore.com (Randell Jesup)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: How to use BPLCON2?
Message-ID: <18999@cbmvax.commodore.com>
Date: 15 Feb 91 04:04:39 GMT
References: <12181@helios.TAMU.EDU>
Reply-To: jesup@cbmvax.commodore.com (Randell Jesup)
Organization: Commodore, West Chester, PA
Lines: 23

In article <12181@helios.TAMU.EDU> aaron@stat.tamu.edu (Aaron Hightower) writes:
>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?)

	Graphics is probably resetting BPLCON2 every vertical blank.  Remember
that the hardware tells you what the hardware does, not how that interacts
with the system software.  You may be able to do it using a user copper
list to set the mode.

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.commodore.com  BIX: rjesup  
The compiler runs
Like a swift-flowing river
I wait in silence.  (From "The Zen of Programming")  ;-)