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My thoughts on this emulator :)

PostPosted: Sat Sep 24, 2011 8:21 pm
by Outrunner
Hello, and congrats on your release of Supermodel 0.2a.

I just tested my Star Wars Trilogy with it and i must say i'm impressed so far, although it could still use some tweaking, but i'm very happy with this emulator progress :) .

The things that I noticed are (also some suggestions) :
1. The sound/music crackles and pops like mad on every voice/music -> consider using a timestretcher so you can avoid buffer overruns/underruns;
2. Also the audio could use some interpolation to increase its quality (Nearest(worst), Linear, Cubic, Hermite, Catmull-Rom(HQ));
3. Maybe an option to set the sample rate, although i doubt it will help with sound quality;

4. I love how you can put the game at what resolution you want (i.e: 1280x1024) the game looks very HQ, i like this.
5. In Star Wars Trilogy there are still some graphical errors :
5.1. The lightsabers are too dark though they look fine when moved;
5.2. The 3D over 2D problem : The 2D of the game should always be rendered in front of 3D otherwise the HUD and other 2D elements will get hidden behind the 3D (i.e: HUD behind Death Star or the Overheat Bar in on foot stages which doesn't appear), appears to be a problem with the Z coordinate of textures or maybe a Z Buffer error (if a Z Buffer exists), can also be a texture BIAS error;
6. I run the PowerPc at 100 Mhz otherwise i get missing/grey textures (i have a 4.2Ghz C2D). Works flawlessly;
7. I ABSOLUTELY love how the controls work, no lag at all and very responsive, plus i can use my mouse to aim in SWT so i'm more than happy :) .

OVERALL: The emulator is a very good and well made one but there is still room for improvement which is to be expected since its only version 0.2. As i remember no good emulators were made overnight :) .

I'm also helping with occasional bug reports on PCSX2 (PS2 Emu) and JPCSP (PSP Emu) so i can also bugtest this :).

Job well done, and keep up the good work !!!

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 1:41 am
by Groni
Thank you for pointing out the Bugs :)

First of all you need to know, that Bart only spended (most) time on including Sound. There has almost no changes been made on the Graphical Engine with exept of the corrected Car Selection
on Daytona and Scud Race. So for this release the most new Part is Sound and Control. I guess there will be more options in the future to set the sound to its optimum.
The Bugs in Star Wars you described are already known and on the Todo for the next releases. First of all a good recompiler for the PPC has to be written before things like that could handle
Stuff like that very well.

Just enjoy the progress so far :) Watch the Step from 0.1 to 0.2 and compare them with Model 2 Emulator Releases :)

Have a good Day :)

GRONI

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 1:55 am
by karadaniano
maybe its me but i think that with this release im having really fullspeed with scud race, the timer goes faster as it has to go.
i still cant believe that scud race is almost perfectly playable on my pc,

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 2:14 am
by Frustrated_Gamer
WOW, with all Caps! This emulator is awesome, filing the gap left from MAME and Model 2/Naomi emulators. Supporting arguably the most anticipated emulated game EVER, Star Wars Trilogy.

Keep up the great work guys, you're amazing!

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 2:51 am
by Bart
Hi Outrunner, thanks for your feedback!

Outrunner wrote:The things that I noticed are (also some suggestions) :
1. The sound/music crackles and pops like mad on every voice/music -> consider using a timestretcher so you can avoid buffer overruns/underruns;


In SWT, I've noticed that the music will occasionally "blip" when looping back to the start. This occurs frequently in Spikeout (about once every 20 seconds or so). In Scud Race, it never occurs, and in Daytona USA 2 and Sega Rally 2, it occurs in one or two of the music tracks and about once per loop. It has nothing to do with buffer underruns/overruns. The audio buffering is quite robust and will work even if Supermodel dips as low as ~10FPS. Rather, I suspect it is due to bugs in the MPEG decoder. I recall hearing the Daytona and Sega Rally blips in R. Belmont's M1 music player, which uses the same decoder.

In the future, we'll probably have to switch to a better decoder.

2. Also the audio could use some interpolation to increase its quality (Nearest(worst), Linear, Cubic, Hermite, Catmull-Rom(HQ));


The SCSP sound effects are generated at 44.1 KHz. There is no interpolation. The MPEG music is generated at 32 KHz and upsampled (linearly) to 44.1 KHz. The MPEG music sound near perfect as far as I can tell. If sound effects seem low quality, that's because they really are that way on the actual hardware (limited sample RAM and all that...).

3. Maybe an option to set the sample rate, although i doubt it will help with sound quality;


It won't.

5. In Star Wars Trilogy there are still some graphical errors :
5.1. The lightsabers are too dark though they look fine when moved;


Known bug. Probably a render-order issue. We either have to sort polygons with respect to their depth value (slow) or figure out precisely which order Model 3 scene graphs ought to be traversed in. For the most part, I think what Supermodel does works well, but the light saber issue is (I suspect) one of the unfortunate corner cases :(

5.2. The 3D over 2D problem : The 2D of the game should always be rendered in front of 3D otherwise the HUD and other 2D elements will get hidden behind the 3D (i.e: HUD behind Death Star or the Overheat Bar in on foot stages which doesn't appear), appears to be a problem with the Z coordinate of textures or maybe a Z Buffer error (if a Z Buffer exists), can also be a texture BIAS error;


It's not that simple. Layer priorities are not well understood yet. Layer priorities can be set not only on a per-layer basis but on a per-tile basis, I suspect.

6. I run the PowerPc at 100 Mhz otherwise i get missing/grey textures (i have a 4.2Ghz C2D). Works flawlessly;


Good to know! I wasn't aware of this. One of our testers did mention that higher PPC frequencies tend to minimize this problem but nobody has ever tried running at such a high frequency. Hopefully if we get a dynamic recompiler hooked up, running at such frequencies will be no big deal :) Right now, I doubt many users can do so.

7. I ABSOLUTELY love how the controls work, no lag at all and very responsive, plus i can use my mouse to aim in SWT so i'm more than happy :) .


Nik did an amazing job with the input system. IIRC, not even a month had passed since v0.1a was released and he emailed me out of the blue with an offer to write a proper input system. The rest is history.

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 8:23 am
by Outrunner
Thanks for the explanations :).

I also noticed that setting the sound in my sound control panel to 24bit 44100hz instead of 24bit 192000hz seemed to eliminate the frequent audio hiccups. The thing is i don't want/shouldn't need to switch my sound driver setting for the sound to work as it should, it should work on any setting.
And yes it blips on music change/loop. I also tested the buffer on 20 fps and it didn't pop or crackle so its an impressive work :).

I agree that most sounds already sound very good with no interpolation, i was just thinking if you could make it even better but if you are focusing on emulation accuracy then forget this :P .

GUI:
For me, there are emulators that need this and others that don't, this one (in my opinion) doesn't need any GUI, i like how you can edit the ini to set the options and consider it the faster way of setting stuff up.

More SWT:
The official Star Wars Trilogy had a 166 Mhz PowerPC but i can't emulate that without slowdown to like 45 fps, probably needs dynarec.

Sega Rally 2:
I noticed that the graphical glitches only appear when the car is far away from the camera(point of view), there might be some postprocessing or bad quality reduction applied to distant objects.
Also the other graphical glitches are the spectators (not the ones on the sides) the ones that stay on the track and run to the side when you get close (tested on the real hardware).

Lost World:
Except for a boss getting sometimes obscured by fog, works flawlessly.

Scud Race Plus:
" PowerPC is out of bounds. Halting emulation until reset. " when trying test menu.

P.S: @Groni : I am enjoying the progress made, but i have the betatester fever of posting bugs :P.

Still, thumbs up :) !!!

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 9:54 pm
by karadaniano
Outrunner wrote:
GUI:
For me, there are emulators that need this and others that don't, this one (in my opinion) doesn't need any GUI, i like how you can edit the ini to set the options and consider it the faster way of setting stuff up.



i think it's not a priority task, but will be important when the dynamic recompiler its ready. i would like to see a gui like the m2 emulator one, simple, intuitive and with a nice logo ;)

Re: My thoughts on this emulator :)

PostPosted: Sun Sep 25, 2011 10:01 pm
by thunderbolt
How to emulate a 166 Mhz PowerPC ?

Re: My thoughts on this emulator :)

PostPosted: Mon Sep 26, 2011 12:06 am
by ector
Dolphin's JIT emulates the 733MHz PowerPC from the Wii at a good speed. Not sure how easy it would be to extract it and put it in Supermodel, it's all pretty tangled, but if anyone needs a project, that's something to try.

Re: My thoughts on this emulator :)

PostPosted: Mon Sep 26, 2011 12:29 am
by Bart
ector wrote:Dolphin's JIT emulates the 733MHz PowerPC from the Wii at a good speed. Not sure how easy it would be to extract it and put it in Supermodel, it's all pretty tangled, but if anyone needs a project, that's something to try.


I've looked at it. It would definitely be doable and easier than writing one from scratch. Still, the recompiler is something I've always wanted to do just to say I've done it. ;)

That said, if someone wants to give it a go for fun, I wouldn't object. Both Dolphin and Supermodel are GPLed, which is nice.