Re: [stella] INV+ Release Candidate 2

Subject: Re: [stella] INV+ Release Candidate 2
From: Erik Mooney <erik@xxxxxxxxxx>
Date: Thu, 08 Apr 2004 01:00:05 -0400
Dennis Debro wrote:

>Hi Erik,
>This is looking good.

>> When in inviso mode, the bombs cannot be seen until they fall
>> below the lowest level of invaders - this is unavoidable.
>Can't you use a missile for the invader bombs?

Missile 1 is already used for the players' missiles (it flickers between
the first and second player's missiles on alternate frames.)  Missile 0 is
unusable for anything because of the shields; to draw those, player 0 is
set to 3 copies via NUSIZ0, and that would also make missile 0 have 3

I could do this by swapping the objects' functions, using the ball for the
players' missiles and missile 1 for the bombs.  However, I'm really loath
to mess with that part of the kernel, and it's not just a simple matter of
changing RESBL to RESM1, as it makes fairly extensive use of the PHP stack
trick (doing so for multiple registers in sequence.)  I'd have to rewrite
all the collision detection as well.  And anyway, this would just shift
the problem and the player's missile would be invisible during the
scanlines with invaders.

>I also agree with Albert. I think this little "feature" of the last few
>invaders getting wiped out in the end should be fixed.

OK, I'll do that.

>Also, when you go to the next round could you start the player back at their
>starting position? Isn't this how the arcade game works?

I checked in MAME and you're right - yeah, I'll put that in too.  (Won't
even take any extra ROM, that's just moving the instruction to set the
player's position into a different subroutine.)

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