AlyoshaTAS Posted April 21, 2016 Share Posted April 21, 2016 Hi all, I am trying to figure out how the score in Kool Aid Man is positioned but I always come up 1 pixel short. The code is: STA HMOVE STA Colbrk STA CTRLPF LDA #$D0 STA HMP0 LDA #$20 STA HMP1 . . . RESP0 RESP1 . . . WSYNC HMOVE So I understand that the first part of the code cuases an effect similar to Cosmic Ark 'starfield effect', where one position clock is eaten up every 4 clocks during hblank and the HMove latches are never cleared. Next we get RESP0 , RESP1 right next to each other. So at this point the players are 9 pixels apart. Then we come to a normal WSYNC, HMOVE In the time it takes to register the HMOVE, the 'starfield effect' has moved player0 3 pixels to the left. The HMove itslef will have a net effect moving player0 3 pixels back to the right, and player1 2 pixels to the left. The net effect is that player0 and player1 are 7 pixels apart. But to display the score correctly they should be 8 pixels apart. So my question is, where does the extra pixel come from? I just can't seem to find it. If anyone could help me account for it I would definitely be grateful! (If it's just that the 'starfield effect' is 4 pixels instead of 3, an explanation of why would also be much appreciated.) Thanks for any insights! Quote Link to comment Share on other sites More sharing options...
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