Edit: Something strange is happening with the game now. It goes to 263 scanlines on seemingly random moments but always at playfieldpos = 0 and 3 lines before the top stump and branches are made. It only happens when the AI is being used. It does not seem to have to do with the missiles and coconut. (although the coconut moving up also seems to have glitched the scanlines too, but only if it also happened on this same scanline.) It also only seems to happen when AI is used. So either the AI code makes the loop too long (Which I do not expect, as then it would happen more often and regurarly?) or it does something that causes the slowdown.
I am a bit at a loss here and it would be great if someone could take a look. I left the rest of this topic in tact so that the answers below make sense. Check here for latest upload: http://atariage.com/...game/?p=4114107
I got a strange error in my game that draws the color slowly every few? frames. The framerate seems to be OK so I am not sure what is wrong and how to google for this error. (Black and white drawing didnt bring up anything.) You don't see it at all in Stella but on real hardware it blinks.
I added a screenshot of the B&W effect and the code.
Edited by Coolcrab, Sat Sep 15, 2018 2:19 PM.