69 replies to this topic

[SeaGtGruff]

Regarding "Bumper Bash," it looks like the positioning of the sprites is being emulated perfectly-- which may mean that all of the HMOVEs are being performed within the visible scan lines, as opposed to during the VBI (if my suspicion about that is correct). But there are still a couple of bugs in the 3.0_alpha1 build. Here are some screenshots from z26, Stella 2.8.4, and Stella 3.0_alpha1 for comparison. The glitches are circled in red.

z26 versus Stella 2.8.4:



The purple slanty-line on the right is drawn with missile1 (the one on the left is drawn with player1), and it should have been drawn 4 color clocks to the right, so it looks like 2.8.4 had an occasional problem positioning missile1-- an examination of the disassembly for the section of the kernel where that part of the screen is being drawn might reveal more clues about exactly what was being done there that may have been a bit different than what was being done in other places. In any case, that particular glitch has been fixed in the 3.0_alpha1 build:

z26 versus Stella 3.0_alpha1:



The other two glitches are still there. The yellow lines on the left are drawn with missile0, and everything looks kosher except for where the line starts to slant inward-- the line's position is okay, but it should be twice as wide (i.e., an HMOVE and a NUSIZ0 change occur on the same scan line).

The purple flippers are drawn with player1, but I'm not certain what the glitch is. It looks like player1 is being drawn with two extra copies, and the graphics for the second extra copy aren't being cleared soon enough, such that the two leftmost bits from the first extra copy are still there. Except, I can't figure out why the programmer didn't just use one extra copy, instead of two extra copies, in which case there'd be no need to clear the graphics before another copy was displayed. Again, a look at a disassembly of the program might reveal more clues about what's being done in that section of the kernel.

Michael

[stephena]

Thanks for the replies so far. Seagtgruff was right in that HMOVE's weren't being done at all on certain scanlines, which is the reason for the glitches in LOTR. This was also the problem in Escape from Mindmaster and Solaris. I've found and fixed the problem. Note that this fixes both issues in LOTR; the title is correct, and the 'cursor' is now in the right spot.

As for the BumperBash problems, I'll look into it right away. I think I know what's going on.

Keep the reports coming ...

EDIT: Also, I forgot to add that I obviously missed last Fridays release. Last week was very busy here, as my sister just had a baby. So I'll push the next release to this coming Friday.

Edited by stephena, Mon Jul 27, 2009 5:32 AM.

[SeaGtGruff]

stephena, on Mon Jul 27, 2009 7:29 AM, said:

Thanks for the replies so far. Seagtgruff was right in that HMOVE's weren't being done at all on certain scanlines, which is the reason for the glitches in LOTR. This was also the problem in Escape from Mindmaster and Solaris. I've found and fixed the problem. Note that this fixes both issues in LOTR; the title is correct, and the 'cursor' is now in the right spot.

As for the BumperBash problems, I'll look into it right away. I think I know what's going on.

Keep the reports coming ...

EDIT: Also, I forgot to add that I obviously missed last Fridays release. Last week was very busy here, as my sister just had a baby. So I'll push the next release to this coming Friday.

I don't think there's any reason you *have* to release a new test build every Friday. I'd say that if you release a new test build on a Friday, and you either don't have time, or don't get enough detailed feedback before the next Friday to fix anything, then just delay putting out another test build until some following Friday.

Michael

[Buzbard]

Here's a glitch in Pole Position (circled in red). This one doesn't appear in 2.8.4 and older.


Oh, and congratulations on your new nephew/niece.

Edited by Buzbard, Mon Jul 27, 2009 7:45 PM.

[Buzbard]

Here are profiles to add to stella, these are for hacks of Kaboom! and Breakout that should have a paddle controller in the left port, but they default to joystick.
 Stella.zip   9.41K   56 downloads

Edited by Buzbard, Mon Jul 27, 2009 10:37 PM.

[stephena]

Buzbard, on Mon Jul 27, 2009 11:11 PM, said:

Here's a glitch in Pole Position (circled in red). This one doesn't appear in 2.8.4 and older.
Pole_Pos..._Atari_3.png

Oh, and congratulations on your new nephew/niece.

This is probably because Pole Position does 'late HMOVEs', which I'm not taking care of yet. In fact, neither 2.8.4 nor the current alpha display that area correctly (it should actually be a 0 digit). Thanks for the profiles; I'll get them integrated soon.

[Wickeycolumbus]

The early versions of Doris have jerky movement (probably the same HMOVE problem). This does not seem to be a problem in the later versions though.

[stephena]

Wickeycolumbus, on Tue Jul 28, 2009 2:25 PM, said:

The early versions of Doris have jerky movement (probably the same HMOVE problem). This does not seem to be a problem in the later versions though.

I just checked this ROM out on a real system, and it's jerky there too. I assume the later versions were fixed because of the feedback from testing on real hardware. So Stella seems to be doing the right thing here.

[Wickeycolumbus]

stephena, on Tue Jul 28, 2009 5:01 PM, said:

Wickeycolumbus, on Tue Jul 28, 2009 2:25 PM, said:

The early versions of Doris have jerky movement (probably the same HMOVE problem). This does not seem to be a problem in the later versions though.

I just checked this ROM out on a real system, and it's jerky there too. I assume the later versions were fixed because of the feedback from testing on real hardware. So Stella seems to be doing the right thing here.

Oh, I did not know that. Glad to here it's not a bug in stella

[stephena]

Wickeycolumbus, on Tue Jul 28, 2009 7:08 PM, said:

stephena, on Tue Jul 28, 2009 5:01 PM, said:

Wickeycolumbus, on Tue Jul 28, 2009 2:25 PM, said:

The early versions of Doris have jerky movement (probably the same HMOVE problem). This does not seem to be a problem in the later versions though.

I just checked this ROM out on a real system, and it's jerky there too. I assume the later versions were fixed because of the feedback from testing on real hardware. So Stella seems to be doing the right thing here.

Oh, I did not know that. Glad to here it's not a bug in stella

This got me thinking about several problem ROMs I was working on yesterday. I tried everything to get rid of a similar 'jitter' in those ROMs, and wasted about 3 hours at it. Finally I decided to try them out on the real thing, and I'll be damned, that's the way they're supposed to be!! I was relying on what several other more 'accurate' emulators should be doing, when in fact they were also wrong all along. Lesson learned; I'll test all new fixes on real hardware first.

[Buzbard]

stephena, on Tue Jul 28, 2009 2:42 AM, said:

In fact, neither 2.8.4 nor the current alpha display that area correctly (it should actually be a 0 digit).

Your right, I didn't have my VCS hooked up so I was comparing 2.8.4 to the alpha version.

Quote

Thanks for the profiles; I'll get them integrated soon.

No problem. I forgot to add Bumper Bash to those profiles.
 Bumper_Bash.zip   770bytes   58 downloads

[stephena]

Well, it looks like I'm going to miss this Friday's release as well. I just got Bumper Bash and Pole Position working, but now I don't have access to an OSX machine until Monday. Look for the alpha2 release then.

[SeaGtGruff]

stephena, on Fri Jul 31, 2009 1:06 PM, said:

Well, it looks like I'm going to miss this Friday's release as well. I just got Bumper Bash and Pole Position working, but now I don't have access to an OSX machine until Monday. Look for the alpha2 release then.

That's cool. We won't be able to test it this weekend, then-- but I'm going to be pretty busy this weekend, anyway. Don't push yourself on this-- you've been pumping out more updates to Stella in the past two years than most emulators have seen in their entire lifespans!

Michael

[stephena]

Buzbard, on Thu Jul 30, 2009 6:38 PM, said:

No problem. I forgot to add Bumper Bash to those profiles.

Hmm, you're right that Bumper Bash uses two paddles in the left port, and each button controls a flipper in the game. I can change it, but then you'd need to press Space and 5 for each flipper. Currently, Stella handles this the same as z26, where it uses a joystick instead, and the left and right flippers are controlled by the left and right joystick directions. The action is exactly the same, but the buttons are more straightforward (cursor keys instead of Space and 5).

Also, this is only for the NTSC version. The PAL version seems to use a joystick.

[stephena]

SeaGtGruff, on Fri Jul 31, 2009 5:45 PM, said:

stephena, on Fri Jul 31, 2009 1:06 PM, said:

Well, it looks like I'm going to miss this Friday's release as well. I just got Bumper Bash and Pole Position working, but now I don't have access to an OSX machine until Monday. Look for the alpha2 release then.

That's cool. We won't be able to test it this weekend, then-- but I'm going to be pretty busy this weekend, anyway. Don't push yourself on this-- you've been pumping out more updates to Stella in the past two years than most emulators have seen in their entire lifespans!

Michael

It's nice to get feedback and especially words of appreciation. While it would be nice to go slower, I want the TIA rework done and over-with. I've been talking about it since 2006, and it's something that keeps beating me over the head every time I want to add new features to Stella. I want it done so I don't have to think about it anymore.

Also, look for an exciting new debugger feature in either alpha2 or the release after that. It's a surprise, to keep people checking back to this thread

[Buzbard]

stephena, on Fri Jul 31, 2009 3:27 PM, said:

Buzbard, on Thu Jul 30, 2009 6:38 PM, said:

No problem. I forgot to add Bumper Bash to those profiles.

Hmm, you're right that Bumper Bash uses two paddles in the left port, and each button controls a flipper in the game. I can change it, but then you'd need to press Space and 5 for each flipper. Currently, Stella handles this the same as z26, where it uses a joystick instead, and the left and right flippers are controlled by the left and right joystick directions. The action is exactly the same, but the buttons are more straightforward (cursor keys instead of Space and 5).

Also, this is only for the NTSC version. The PAL version seems to use a joystick.

Hmmm, you're right, the pal version does use the joystick, it uses left and right to adjust the plunger then up to the launch the ball, where the ntsc version can use the joystick but it requires both left and right (aka both paddle buttons) at the same time to launch the ball, kinda hard to do with a joystick.

[stephena]

Buzbard, on Sat Aug 1, 2009 2:49 PM, said:

stephena, on Fri Jul 31, 2009 3:27 PM, said:

Buzbard, on Thu Jul 30, 2009 6:38 PM, said:

No problem. I forgot to add Bumper Bash to those profiles.

Hmm, you're right that Bumper Bash uses two paddles in the left port, and each button controls a flipper in the game. I can change it, but then you'd need to press Space and 5 for each flipper. Currently, Stella handles this the same as z26, where it uses a joystick instead, and the left and right flippers are controlled by the left and right joystick directions. The action is exactly the same, but the buttons are more straightforward (cursor keys instead of Space and 5).

Also, this is only for the NTSC version. The PAL version seems to use a joystick.

Hmmm, you're right, the pal version does use the joystick, it uses left and right to adjust the plunger then up to the launch the ball, where the ntsc version can use the joystick but it requires both left and right (aka both paddle buttons) at the same time to launch the ball, kinda hard to do with a joystick.

There is specific code in Stella for this case, where all directions are allowed on the joystick. Normally, this isn't enabled, and it obviously isn't possible on a real joystick. I prefer to leave it that way, since it means you can use basically the same controls for both ROMs in Stella.

[stephena]

Bumped thread for alpha2 release.

[Thomas Jentzsch]

I love the debugger "undo" function!

[e1will]

stephena, on Sat Aug 1, 2009 4:07 PM, said:

There is specific code in Stella for this case, where all directions are allowed on the joystick.

Would this be possible to enable this via a configuration setting? I remember having a joystick back in the early 80s that would stick to the left or right for a second or two after releasing it, and quickly moving between left and right would cause the VCS to do some pretty neat tricks.

For example, in Combat, left + right would let you zoom the tank forward extremely quickly (it even gave you a "in a higher gear" sound.) Might be fun to see what other games have hidden behind "impossible" joystick combinations.

Obviously not an essential emulator feature, but kind of a fun one and (probably) easy to add.

--Will

[e1will]

Also, could please consider adding a config option to disable fullscreen mode? Or at least the option to remap the Alt-Enter combination?

Stella seems to occasionally "remember" the Alt key being pressed when you Alt-Tab to it from another application in Windows, and when you press Enter to start the highlighted game, it treats it as Alt-Enter instead, and instead of launching the game, does this:

Obviously there's a problem with my OS in that it doesn't support full-screen mode, but it shouldn't have to, IMO.

--Will

Attached Thumbnails

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[stephena]

e1will, on Tue Aug 4, 2009 5:35 PM, said:

stephena, on Sat Aug 1, 2009 4:07 PM, said:

There is specific code in Stella for this case, where all directions are allowed on the joystick.

Would this be possible to enable this via a configuration setting? I remember having a joystick back in the early 80s that would stick to the left or right for a second or two after releasing it, and quickly moving between left and right would cause the VCS to do some pretty neat tricks.

It's easy enough to expose this as a setting in the UI. However, be aware that it also breaks a few ROMs (Astroblast and Berzerk really don't like it). I'll look into it.

e1will, on Tue Aug 4, 2009 5:44 PM, said:

Also, could please consider adding a config option to disable fullscreen mode? Or at least the option to remap the Alt-Enter combination?

This is also pretty easy to add.

[e1will]

stephena, on Tue Aug 4, 2009 4:50 PM, said:

This is also pretty easy to add.

Awesome! Thanks!

--Will

[Buzbard]

e1will, on Tue Aug 4, 2009 12:14 PM, said:

Stella seems to occasionally "remember" the Alt key being pressed when you Alt-Tab to it from another application in Windows, and when you press Enter to start the highlighted game, it treats it as Alt-Enter...
--Will

Sounds like you have the "Sticky-Keys" feature turned on in Windows.

[e1will]

Buzbard, on Tue Aug 4, 2009 7:27 PM, said:

Sounds like you have the "Sticky-Keys" feature turned on in Windows.

Nope, this is a sporadic thing. Only seems to happen about every 10th or 20th time. Open up Stella and Notepad, and Alt-Tab between them enough times and you'll see it too. From Notepad, Alt-tab to Stella, hit Enter to load whatever game is selected, exit the game, Alt-tab back to Notepad, and repeat.

(And I long ago disabled Sticky Keys and some other "helpful" Windows features.)

--Will