Gurner Posted December 3, 2013 Share Posted December 3, 2013 Really enjoy playing this on real hardware but get jitters (don't get them on original Circus Atari). Is there a later version that doesn't jitter? (PAL, or even better, PAL 60.) Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 3, 2013 Share Posted December 3, 2013 Hi Gurner, thank you for playing my game. The jitter is not from the game, it is from your paddles. They get dirty and start jumping around. Here are some instructions on how to clean them: http://atariage.com/forums/topic/70340-paddle-maintenance/ For other people who don't know about this game, here is the Circus AtariAge thread: http://atariage.com/forums/topic/207391-circus-atariage-2600/ I didn't work on this game at all in two months until spending a couple of hours on it Sunday. It felt really good getting back into it again. It will be a long while until an update though... For sure there will be a PAL60 version in the end!! Quote Link to comment Share on other sites More sharing options...
AtariBrian Posted December 3, 2013 Share Posted December 3, 2013 (don't get them on original Circus Atari). To me it looks like hes saying they dont jitter for the original circus , so then it couldnt be his paddles could it ? Quote Link to comment Share on other sites More sharing options...
+FujiSkunk Posted December 3, 2013 Share Posted December 3, 2013 I wonder, is the OP referring to paddle jitter or video jitter? Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 3, 2013 Author Share Posted December 3, 2013 Hi Gurner, thank you for playing my game. The jitter is not from the game, it is from your paddles. They get dirty and start jumping around. Here are some instructions on how to clean them: http://atariage.com/forums/topic/70340-paddle-maintenance/ For other people who don't know about this game, here is the Circus AtariAge thread: http://atariage.com/forums/topic/207391-circus-atariage-2600/ I didn't work on this game at all in two months until spending a couple of hours on it Sunday. It felt really good getting back into it again. It will be a long while until an update though... For sure there will be a PAL60 version in the end!! Hi Omegamatrix – awesome to hear you're continuing work on it, and the PAL 60 news too! The paddles are brand new old stock http://atariage.com/forums/topic/219244-eye-candy-old-new-stock-atari-paddles/ and the original Atari Circus (and other paddle games) don't jitter. The see-saw jitters left and right, only at certain positions on the screen by about half a centimetre (quarter inch) – this is on the Harmony Cart too, I probably should mention, so could be something to do with that? I'm playing the rom that says Early Demo at the bottom, not sure if this is the latest version? BTW – Very impressive the way the Harmony Yin-Yang rolls to the side to become your logo! Very cool to see new paddle games. Playing the black background at night on a CRT TV with the lights off leaves a cool streaking effect as the white sprite moves. Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 3, 2013 Share Posted December 3, 2013 I will look tonight or tomorrow. I had this problem too and haven't cleaned my paddles yet. I might switch to reading every 2nd line if clean paddles still Jitter but I think clean paddles will solve the problem. Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 3, 2013 Author Share Posted December 3, 2013 I will look tonight or tomorrow. I had this problem too and haven't cleaned my paddles yet. I might switch to reading every 2nd line if clean paddles still Jitter but I think clean paddles will solve the problem. Cheers Omegamatrix. Also, I'm PAL, not sure if that would make any difference? Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 4, 2013 Share Posted December 4, 2013 Cheers Omegamatrix. Also, I'm PAL, not sure if that would make any difference? PAL console, nope, no difference. What kind of Atari are you using though? I played around with it tonight, but no fix yet. Maybe this weekend. My paddles are a little jumpy, and I thought the game was fine before now. My paddles jump sometimes on the Harmony menu, during Medieval Mayhem, etc... but not in the original Circus Atari like you said. From playing around in Stella it appears that the original has a smoothing routine which slows you down as you get closer to each ledge. It's quite smooth... but slower then CAA. I'm going to look at it more as it is smooth while other games are not. CAA currently reads single line resolution (like Circus Atari), but positions the see-saw on the same screen right after the value is read! Most games use the value read from the previous frame. CAA was shooting for fast reflexes tough. The jitter is a problem, and I'm really glad you found this and brought it to my attention as I really didn't know about it. I thought it was just my paddles. Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 4, 2013 Author Share Posted December 4, 2013 PAL console, nope, no difference. What kind of Atari are you using though? I played around with it tonight, but no fix yet. Maybe this weekend. My paddles are a little jumpy, and I thought the game was fine before now. My paddles jump sometimes on the Harmony menu, during Medieval Mayhem, etc... but not in the original Circus Atari like you said. From playing around in Stella it appears that the original has a smoothing routine which slows you down as you get closer to each ledge. It's quite smooth... but slower then CAA. I'm going to look at it more as it is smooth while other games are not. CAA currently reads single line resolution (like Circus Atari), but positions the see-saw on the same screen right after the value is read! Most games use the value read from the previous frame. CAA was shooting for fast reflexes tough. The jitter is a problem, and I'm really glad you found this and brought it to my attention as I really didn't know about it. I thought it was just my paddles. Thanks for looking into it – I read on another thread here that someone said Circus Atari was their go-to game they could play for hours. I'd have to agree and like the faster-paced action on CAA. Atari Age should make CAA one of the High Score games once it's finished. Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 4, 2013 Share Posted December 4, 2013 I took a look and Circus Atari simply averages 2 frames to smooth things out. I will try dropping this in. I think it will help with slightly jittery paddles too. Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 4, 2013 Author Share Posted December 4, 2013 I took a look and Circus Atari simply averages 2 frames to smooth things out. I will try dropping this in. I think it will help with slightly jittery paddles too. Nice one! Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 8, 2013 Share Posted December 8, 2013 Just posting an update. The averaging between 2 frames didn't solve the problem. I am still investigating this. I have changed and tried many things now, but I'm at the point where I have to strip parts of the code away to see if it is software related. I've fully disassembled and cleaned my paddles. This actually stopped the big bounces, but some little ones remain. 1 Quote Link to comment Share on other sites More sharing options...
RevEng Posted December 9, 2013 Share Posted December 9, 2013 You might try a median filter on 3 bytes of rolling paddle data, instead of using averaging. Averaging blurs noise, but a median filter can remove small to medium amounts of it. Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 9, 2013 Share Posted December 9, 2013 You might try a median filter on 3 bytes of rolling paddle data, instead of using averaging. Averaging blurs noise, but a median filter can remove small to medium amounts of it. I've haven't tried this, but right now I'm looking for root causes. For example there is almost always a bounce when I press the fire button, but only at certain see-saw positions. I'm trying to work out if it is hardware related. I've cleaned the paddles, and other games don't do this (like the original Circus Atari). I was thinking parasitic capacitance was contributing to the problem... or induction from the rush of current when the firebutton grounds. Either way I would expect other games to have the same behavior. I was writing to VBLANK in a few places before. I cut that out (still no success) and tried making the writes like Circus Atari did, although I'm not reading the paddles on exact same scanlines as Circus Atari yet. I also looked at where Circus Atari reads the firebutton (in SWCHA for paddles), and moved that there too. Still didn't work. A big problem is that the places of the pot CAA and Circus Atari read are different. It is not a simple one to one comparison where since one works the other should too. As I peel more code away I am going to try and get CAA running with the exact same timed writes to VBLANK and scanlines the paddles are read on as Circus Atari. Then I will really be able to see if something is up. There is no guarantee that every set of paddles out there will have a sweet spot, but I have to strip as much away and make them as close as possible to get the clear picture. I was also incorporating a dead band in software where the paddle would have to move a significant amount before the see-saw would go. I was also going to try a moving average filter. The spikes seem to be too huge though, so I'm trying to find the problem. Quote Link to comment Share on other sites More sharing options...
RevEng Posted December 9, 2013 Share Posted December 9, 2013 For sure, nailing the root cause is the best way to go. It seems that its at least partially hardware, since you see some noise with paddle movement in the Harmony menu and Medieval Mayhem, and none in CAA in Stella. Perhaps your 2600 is bordering on not getting enough current. Are you running Circus Atari via Harmony? I know you'll solve this one way or another, I just wanted to put my 2 cents on using a median filter vs averaging filter for noise removal. Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 10, 2013 Share Posted December 10, 2013 Perhaps your 2600 is bordering on not getting enough current. Are you running Circus Atari via Harmony? This is also something I have considered. I have no means to burn a cart so I am using my harmony, and I don't have a bigger power supply available but it was one of the first things that popped in my mind. I ripped the balloon kernels completely out and the jitter is still there. That was a big worry for me... I could deal with other things missing in my game but not the balloon kernels if they didn't work. That was the initial motivation for CAA in the first place. Once I find this bug (hopefully it's a software bug that somehow Stella missed) I will try the median filter to see how the paddles respond. Then I can keep playing with it all, dead bands, averaging 2 frames, or a median filter to see what gives the best results. 1 Quote Link to comment Share on other sites More sharing options...
Omegamatrix Posted December 23, 2013 Share Posted December 23, 2013 I think I got it fairly stable now. PAL60 build is here: http://atariage.com/forums/topic/207391-circus-atariage-2600/?p=2891028 Please direct any questions comments to the main CAA thread. Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 23, 2013 Author Share Posted December 23, 2013 I think I got it fairly stable now. PAL60 build is here: http://atariage.com/forums/topic/207391-circus-atariage-2600/?p=2891028 Please direct any questions comments to the main CAA thread. Awesome, will stick it on the Harmony! Quote Link to comment Share on other sites More sharing options...
Gurner Posted December 26, 2013 Author Share Posted December 26, 2013 Have tested on the Harmony (PAL Vader) – runs like a dream! Not a shudder in sight, cheers Omegamatrix, for a perfect ROM! Quote Link to comment Share on other sites More sharing options...
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