[comp.sys.amiga.tech] Bug In MakeVPort

barnettj@dollar.steinmetz (janet a barnett) (02/09/89)

I defined a dual playfield viewport with 5 planes, 3 foreground, 2
background.  I also turned on the SPRITES flag.  MakeVPort, however,
only generated copper instructions to load color registers 0 through
15, even though I had attached a 32 color colormap.  Is this a known
bug?

brett@sylvester (Brett S Bourbin) (02/10/89)

In article <13097@steinmetz.ge.com> barnettj@dollar.UUCP (janet a barnett) writes:
>I defined a dual playfield viewport with 5 planes, 3 foreground, 2
>background.  I also turned on the SPRITES flag.  MakeVPort, however,
>only generated copper instructions to load color registers 0 through
>15, even though I had attached a 32 color colormap.  Is this a known
>bug?

Yes, I had the same problem when I wanted a HAM screen with the V_SPRITES
bit set in my v_Modes.  I have never heard anything offical from CATS if
this was truly a bug in the graphics routine, but it is reproducable on
a standard machine.

What I did to get around this "bug" is create a user copper list just below
the top of the screen to load the sprite color registers.  A bit of a hack
and you can not use the SetRGB() function on these registers, but it
works and is legal. (Right JimM?  8^) )


--Brett S Bourbin
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