Author Topic: Stella 3.9.3 Atari 2600 emulator  (Read 7145 times)

David Knight (OP)

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Stella 3.9.3 Atari 2600 emulator
« on: October 06, 2015, 10:55:46 pm »



Here is a new version of Stella,the Atari 2600 emulator.

AtariHERO has been persistently requesting a new version  (that's not counting the PM's  ;)). I have used version 3.9.3 of the source code as later versions seem noticeably slower.

IMPORTANT!
If you have run any previous version of Stella you must delete your $HOME/.stella/stellarc file first or you will have numerous control problems with this version.

You have been warned!

This version has triple buffering enabled, reconfigured feature-full menu's with mouse emulated navigation via the A-stick , remapped controls and optimised rendering speed.

For controls see the manual or the helpfile in the menu. All controls are reconfigurable from the menu.

Default controls:
D-pad/A-stick: Joystick movement
A: Joystick fire
B: Select
X: Command menu
Y: Fire5
L: Load Savestate
R: Save Savestate
SELECT: Reset
START: Main menu

Menu controls:
A-stick: Mouse cursor movement
A: Left click
B: Previous menu/exit menu
D-pad: Navigate menu tables
L: Tab between options
START: Select highlighted button

The source code
https://github.com/DavidKnight247/Stella-3.9.3

The opk
https://drive.google.com/file/d/0BwYi4RGX-HSaaFJvTmxwc01mYU0/view?usp=sharing

@AtariHERO yes I am working on the A8 emu  ;).

AtariHERO

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #1 on: October 07, 2015, 12:47:37 am »
so good  :)

opt2not

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #2 on: October 07, 2015, 01:19:06 am »
Thanks, David, for the very sexy release!  ;)

chevette

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #3 on: October 07, 2015, 02:20:59 am »
Thanks David for this great release! Pitfall II runs great, as do the Starpath games.

iesposta

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #4 on: October 08, 2015, 04:04:31 am »
Thank you, David Knight!

Stella Version 3.9.3 will play nearly everything and anything worth playing, old AND new, up to now... we're not done innovating and pushing this system... -- stock system amazingly!

No Processor Overclocking or RAM adding internally (it has 128 bytes of RAM or 1/8th of a Kilobyte). Think about that a second. One eighth of 1K RAM - 128 bytes. We can add RAM at the cartridge even though they did not design for that...


David Knight (OP)

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #5 on: October 08, 2015, 02:01:42 pm »
I'll just answer this old post here:

Can this emulator run games without any scaling/stretching? I've read Atari 2600 games run at 160x192, although the vertical resolution may vary. This means, the horizontal image can be doubled in size to fit the 320 pixels, so the result would be a sharp image, without any hint of scaling.



If you look at a screenshot of Stella there is no blending, just crisp pixels.

The GCW0 version is rendering a 320x240 screen. Stella internally horizontally scales the image from 160 to 320 so it just renders two of the same pixel at a time. There is no vertical scaling. From the optimising perspective, the GCW0 hardware scaler doesn't scale horizontally (as far as I know) so wouldn't be of much use here yes it probably does if you turn off aspect ratio preservation. Even if you could use the GCW0 hardware scaler for this task it is unlikely to produce significant speed gains.

However the actual resolution of the Atari is not easily definable due to the way it uses the CPU to render. There is an interesting (5 yr old) discussion on this subject here.

Here is an interesting youtube video about Atari 2600 rendering, the Atari 2600 part starts at 3:24.
<a href="https://web.archive.org/web/20190314074813/https://www.youtube.com/watch?v=_rsycfDliZU" target="_blank">https://www.youtube.com/watch?v=_rsycfDliZU</a>
« Last Edit: October 08, 2015, 02:26:10 pm by David Knight »

David Knight (OP)

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #6 on: October 08, 2015, 02:51:01 pm »
From the optimising perspective, the GCW0 hardware scaler doesn't scale horizontally (as far as I know) so wouldn't be of much use here yes it probably does if you turn off aspect ratio preservation. Even if you could use the GCW0 hardware scaler for this task it is unlikely to produce significant speed gains.

I just compiled a quick and dirty test version with hardware horizontal scaling to test. As expected I cannot see a speed difference between the two versions. I'll still probably end up implementing it anyway though  ;)

Senor Quack

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #7 on: October 08, 2015, 03:02:47 pm »
Quote from: David Knight
From the optimising perspective, the GCW0 hardware scaler doesn't scale horizontally (as far as I know) so wouldn't be of much use here yes it probably does if you turn off aspect ratio preservation. Even if you could use the GCW0 hardware scaler for this task it is unlikely to produce significant speed gains.

If there's no speed difference, and I doubt there is since all it's doing is software pixel doubling, I think it's probably best just to leave it that way. Using the IPU would just drain the battery faster with nothing to gain. You'd also not get complaints from people still running older firmwares that don't support the IPU.
After speaking with Surkow, I realized I neglected to account for one large advantage to adding IPU support: when HDMI/TV-out gets implemented. it would allow seamless scaling to any dimension. So, perhaps add an option to use either software scaling (for when not using TV-out/HDMI), and hardware scaling (works for any case).
« Last Edit: October 08, 2015, 03:29:56 pm by Senor Quack »

CSX

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #8 on: October 09, 2015, 04:48:10 pm »
I can't see .a26 files in the file browser. Is there anything I can do to fix it?

David Knight (OP)

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #9 on: October 09, 2015, 08:35:22 pm »
I can't see .a26 files in the file browser. Is there anything I can do to fix it?

It would need the correct mimetype in the desktop file. I'm not sure what this would be though. According to the web it's application/octet-stream. If this works I'll update the opk when I've added the IPU scaler option.
« Last Edit: October 09, 2015, 08:39:57 pm by David Knight »

gameblabla

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #10 on: October 09, 2015, 09:47:12 pm »
I can't see .a26 files in the file browser. Is there anything I can do to fix it?

It would need the correct mimetype in the desktop file. I'm not sure what this would be though. According to the web it's application/octet-stream. If this works I'll update the opk when I've added the IPU scaler option.
application/octet-stream is just the mime type for every file that does not have one mime type.
SPOILER: IT WILL NOT WORK !!!

qbertaddict

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #11 on: October 10, 2015, 12:55:34 am »
I can't see .a26 files in the file browser. Is there anything I can do to fix it?

If you are in windows you can go to a command prompt and cd to the directory and rename all your .a26 to .bin then copy them to your gcw and they will be recognized by the file browser

example:

cd d:\gcw\roms\A2600
ren *.a26 *.bin


Make sure you backup your roms first though


David Knight (OP)

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #12 on: October 10, 2015, 10:24:30 pm »
I can't see .a26 files in the file browser. Is there anything I can do to fix it?

It would need the correct mimetype in the desktop file. I'm not sure what this would be though. According to the web it's application/octet-stream. If this works I'll update the opk when I've added the IPU scaler option.
application/octet-stream is just the mime type for every file that does not have one mime type.
SPOILER: IT WILL NOT WORK !!!

application/octet-stream was already in the desktop file!

Unfortunately the GMenu doesn't recognise .a26 files currently. For now you will need to change the extension to .bin using qbertaddicts Windows code or the equivalent linux command:

Code: [Select]
cd /path/to/roms
rename 's/\.a26$/\.bin/'

EDIT: Forgot mv doesn't like batch renaming  :-[
« Last Edit: October 10, 2015, 10:32:03 pm by David Knight »

Qubits

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #13 on: June 08, 2016, 11:20:09 pm »
I have a question... how do you make the games look centered ? i've tried all options in the emulator without success, here is how pitfall look like, is there a way to have it centered without the black bar on the left ?

David Knight (OP)

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #14 on: June 17, 2016, 05:28:26 am »
I have a question... how do you make the games look centered ? i've tried all options in the emulator without success, here is how pitfall look like, is there a way to have it centered without the black bar on the left ?

Hi, sorry for the late reply. I believe this is deliberate. See the Stella FAQ for details.

gameblabla

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #15 on: June 17, 2016, 05:51:06 am »
I have a question... how do you make the games look centered ? i've tried all options in the emulator without success, here is how pitfall look like, is there a way to have it centered without the black bar on the left ?

Hi, sorry for the late reply. I believe this is deliberate. See the Stella FAQ for details.
Maybe you should allow users to move the surface instead ?
This should not be too difficult to implement.

AtariHERO

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #16 on: June 17, 2016, 02:13:25 pm »
original pitfall and many activision releases on real hardware have the left black column to hide the 2600 usual black lines
its a sacrilege to modify that  ;)

Qubits

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #17 on: June 17, 2016, 04:22:11 pm »
Well if you love to play the games off-centered with a black bar just because it has this bug on the original console, i dont. I would prefer to have the game centered as it obviously looks better. Why keep a deffect just because it was on the original console while you can now correct it ?
« Last Edit: June 17, 2016, 10:32:24 pm by Qubits »

AtariHERO

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #18 on: June 17, 2016, 08:35:25 pm »
then let?s correct the dozens of games with horizontal black lines that are there because the 2600 chip had to display them whie moving objects on the fly or  well lets give 50 sprites / screen , the games would be better ...
but its not the 2600 anymore ...

Qubits

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Re: Stella 3.9.3 Atari 2600 emulator
« Reply #19 on: June 17, 2016, 10:30:16 pm »
We are just talking about the off centering problem that is well known for atari 2600 games, not to transform the emulator into a Dreamcast.