popmilo Posted February 24, 2014 Author Share Posted February 24, 2014 You have to turn off PAL Blending.That did it, now the difference is obvious. Looks like two more cycles are free with higher values of HSCROL. Could be critical in the long run, and doesn't cost anything to implement now Quote Link to comment Share on other sites More sharing options...
Xuel Posted February 24, 2014 Share Posted February 24, 2014 Yep, all thanks to Rybags for originally introducing me to the concept in the PAL Blending thread. It helped me squeeze the color changes into the horizontal blanking period so they didn't bleed into the playfield area. Quote Link to comment Share on other sites More sharing options...
Xuel Posted February 24, 2014 Share Posted February 24, 2014 Hey, you were in that thread and even liked my post! 1 Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted February 24, 2014 Share Posted February 24, 2014 Hscrol12-15 is nice Quote Link to comment Share on other sites More sharing options...
popmilo Posted February 24, 2014 Author Share Posted February 24, 2014 Hey, you were in that thread and even liked my post! Well, we all move in same circles, pushing on retro code boundaries Compared to your code in that thread, situation is better in bitmap mode. There are no badlines so more cycles are available anyway. Lot's of potential here... Quote Link to comment Share on other sites More sharing options...
Xuel Posted February 24, 2014 Share Posted February 24, 2014 Yeah, yeah, I knew you were there cuz you did those awesome graphics that inspired me to try PAL Blending in the first place, but I was just teasing you that you liked a post where I showed the Shift-F8 thing over a year ago. Anyhooo... looking forward to what you've got cooking. 1 Quote Link to comment Share on other sites More sharing options...
+playsoft Posted February 24, 2014 Share Posted February 24, 2014 Another thing, don't forget you can use the high range of HSCROL values to reduce DMA. In other words, instead of using HSCROL 0-3, use 12-15. This prevents ANTIC from halting the 6502 for several cycles at the beginning of each scan line. Hit Shift-F8 in Altirra to see the DMA pattern shrink in comparison. Thank you so much, I did not know about this... and it's not often you get cycles for free! 1 Quote Link to comment Share on other sites More sharing options...
Xuel Posted February 24, 2014 Share Posted February 24, 2014 Thank you so much, I did not know about this... and it's not often you get cycles for free! Cool! You just have to remember to adjust the coarse scrolling forward by 3 bytes, but it looks like you may have already figured that out seeing as your graphics show up at the same Y position in both cases. 1 Quote Link to comment Share on other sites More sharing options...
+playsoft Posted February 24, 2014 Share Posted February 24, 2014 Cool! You just have to remember to adjust the coarse scrolling forward by 3 bytes, but it looks like you may have already figured that out seeing as your graphics show up at the same Y position in both cases. Yes I'd added the offset and compared to what I was doing before I'm saving on average 2.5 cycles on those scan lines which is fantastic thank you. Quote Link to comment Share on other sites More sharing options...
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