EarthQuake Posted November 12, 2008 Share Posted November 12, 2008 (edited) So I was working on my Adventure hack a bit, overwhelmed with the new possibilities given Nukey's new kernal. Basically, each line of the playfield data has it's own value (stored in the lower nybble of the byte sent to PF0), which allows not only higher vertical resolution in bitmaps, but screen bitmaps where each playfield row can be of variable height, so you can increase the vertical resolution only where you need it. But, anyways, I was wondering about something and it might just be possible. IIRC, the bit in the playfield control register that controls the mirroring, could theoretically be switched on and off as the screen bitmap is drawn to achieve a playfield layout that is somewhat non-symmetrical. The engine could look for a certain bit set in the screen bitmap's PF0 byte and XOR the bit sent to the playfield register, effectively toggling it each time the condition is met. I know I'm always going on about how Adventure could extremely benefit from asymmetrical playfields, but this idea could be a great compromise. Would this even be possible? It's a long shot, but I can see amazing things resulting from this. Here's a textual result of a room that would take advantage of such an addition: .byte $F0,$FF,$0F;XXXXXXXXXXXXXXXX RRRRRRRRRRRRRRRR .byte $30,$00,$00;XX RR .byte $30,$00,$00;XX RR .byte $F0,$C0,$FC;XXXXXX XXXXXXRRRRRR RRRRRR .byte $30,$00,$00;XX MM <- * .byte $30,$00,$00;XX MM .byte $F0,$FF,$FF;XXXXXXXXXXXXXXXXXXXXMMMMMMMMMMMMMMMMMMMM * Playfield register updated on noted line. The value specified in the room data table could perhaps just be used as the initial value of the mirroring behavior. Edited November 12, 2008 by EarthQuake Quote Link to comment Share on other sites More sharing options...
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