Subject: Re: [stella] Horizontal Positioning once more... From: Manuel Polik <cybergoth@xxxxxxxx> Date: Wed, 08 Aug 2001 10:40:24 +0200 |
Thomas Jentzsch schrieb: > > I try to eliminate the blank HMOVE lines via doing HMOVE on cycle 74. > > There the HMXX values are shifted 8 pixel into the negative. To > > compensate that, I just tried adding 8 at the beginning of my > > positioning routine. > > Now, when coming close to the end of the screen with any value >164 the > > routine no longer functions properly. > Try positioning at X modulo 160, I think that should solve the problem. > Correct me, if I'm wrong :) It worked! *bounce* Thanks! BTW: In QB, there's this sethorpos routine, written by Andrew and improved with suggestions from you. I've just found yet another improvement! Looky here! This is the end of the routine in QB: ---------------------------------------- sta HMP0,x sta WSYNC jsr Ret ; Waste 12 cycles, 3 Byte bit 0 ; Waste 3 cycles, 2 Byte ; + sum: 15 cycles, 5 Byte Jiggle dey bpl Jiggle sta RESP0,x ---------------------------------------- Here's my idea: ---------------------------------------- STA HMP0,x INY ; Waste 5 cycles, 1 Byte STA WSYNC INY ; Waste 7(!) cycles, 1 Byte BIT 0 ; Waste 3 cycles, 2 Byte ; + sum: 15 cycles, _4_ Byte!!! PosDelay dey bpl PosDelay STA RESP0,x ---------------------------------------- Apart from saving a byte, it prevents you from possibly losing another two byte to the stack... (Avoiding that was my original intention, in Gunfight there's _never_ a subroutine call within a subroutine call within a subroutine :-)) Greetings, Manuel - Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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