Re: [stella] Poker Solitaire

Subject: Re: [stella] Poker Solitaire
From: Manuel Polik <cybergoth@xxxxxxxx>
Date: Thu, 22 Nov 2001 20:45:55 +0100
Hi Brian!


Is it Brion? :-)

>2) I use it inside the kernel, like so:
> repeat 2
> (do one scanline of complex stuff)
> repend

>...which has the effect of drawing 2 identical 
scanlines, one after the
>other. In a 2-line low-res kernel where you're 
modifying GRP0/1 on the
>fly, you have to modify them the same way for each one 
of the 2 lines...
>Sure, I could convert to a single-line kernel, but then 
I'd have to have
>twice as much sprite data... or else draw squashed, 
half-height cards..

>Alternatively, I could get rid of the repeat/repend, 
and just paste
>an identical copy of the code... but that's less 
maintainable (have to
>make all changes twice)

Well, the status line in Gunfight is in 2LK resolution, 
executing 6 (),Y reads & 6 GRPX writes plus 2 color 
changes per line _and_ is using only ROM space for 
one(!) line :-)

Here it is:
                    LDX #$0D   ; 7 lines to draw
                    LDY #$06   ; Again 7 lines :-)
NextDigitLine:      STA WSYNC
                    STY COLUP0
                    STY COLUP1
                    LDA (tempVar1),Y         ;
                    STA tempVar3
                    LDA (obstaclePtr00),Y         ;
                    STA GRP0            ;
                    LDA (obstaclePtr01),Y         ;
                    STA GRP1            ;
                    LDA (obstaclePtr02),Y         ;
                    STA GRP0            ; 
                    LDA (horPosM0),Y         ; 
                    STA GRP1            ; 
                    LDA (movementBuffer),Y         ; 
                    STA GRP0            ; 
                    LDA tempVar3         ; 
                    STA GRP1            ;
                    BPL NextDigitLine   ;Draw next line

Speaking of your kernel, you'd save both COLUBK writes 
when centering your view and doing 5 PF cards only.

And I somehowassume that the TXS/TSX cycles are 
currently wasted too.

>But if you really hate the repeat/repend, look again... 
85% of the kernel is:

I don't hate it, I only think it pushes you easily into 
coding sins that the VCS just won't forgive :-)

>Tell you what though... when I do get the game 
functional, I'll go back through
>all this space-wasting inefficient crap, and clean it 
up some. Right now I'm
>trying to explain to my 2600 that 3 clubs and 2 
diamonds is *not* a flush, and
>that if you have 3 of a kind, it doesn't also count as 
a pair! :)

Good Luck on your quest,

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