RE: [stella] JoustPong: more exciting than ever!

Subject: RE: [stella] JoustPong: more exciting than ever!
From: Christopher Tumber <christophertumber@xxxxxxxxxx>
Date: Mon, 23 Feb 2004 11:06:39 -0500
>You slightly underestimate the semi-cleverness of my flicker
>algorithm but your point is valid.

Ah, okay, same difference, really...

>Basically what you're saying to do is move my exact repositioning 
>routine to between the score and the action.  

Yeah, though you'd also need seperate positioning code for the score itself.

>I'd have to do it 
>at most once I think at the cost of 2 or so scanlines, since I
>can put the score above each player, and then there's just a 1 
>in 2 chance I have to move one of the players to be Pterry.  

Yeah, exactly.

>It might be worth looking into...but I'm not sure, since I
>think right now I have the ball bouncing off the 'ceiling'...
>I'd have to be very careful about when I turn off the BGCOLOR
>for that....

You have a few white scanlines right below the score digits, maybe they're be available?

You can shift everything down a couple scanlines, 262/192 scanlines is not really a hard and fast rule.

>I'll take a look into it, though behind making Pterry movement
>more interesting, dumbidfying the AI, tweaking the physics,
>and fixing my title screen frame bug....

Yeah, there's something to be said for just having a stable kernal, even if it isn't the final, final, final one just so you can get other work done.

Could Pterry's movement just mimic the ball's (and probably share a bunch of code) except at 1/2 or 1/4 speed? And then when they collide they'd both change direction slightly...

BTW - While we're redesigning your kernal (smile) what if:

Ball = Ball
Pterry = P0
Right player = P1
Left player = M0+M1

You could then have a flicker free kernal (Scores would be P0/P1 but that doesn't really effect the play area)

Each scanline you'd need to:

Turn ball on or off
Load values into left and right playfield
Load bitmap value into P0
Load bitmap value into P1
Turn M0 and M1 on or off
Adjust position/width of M0 and/or M1 (depending upon how complex the paddles will look)
Fix COLUP0 and COLUP1 so left player, right player and Pterry are different colours

Could be do-able (smile).


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