Hi ALL!

Since I read around of news ports of MAME for our OLD hw...
Why dont simply port the very good(and FAST) MAME4ALL:

http://chui.dcemu.co.uk/mame4all.html

on our systems? With iur hw we dont need recent MAME versions imho, simply an old one(0.37 based as that) optimized with GUI and OS relatd support...

Why look for a newver version that was:

- SLOW
- support games that we cant run (for the speed reasons)

instead of a nice one that can grant us full speed games withou frameskip also on Sam440?

What do you think?

Last edited by Tuxedo on 03-Mar-2013 at 03:01 PM.
Last edited by Tuxedo on 03-Mar-2013 at 03:00 PM.

_________________
Simone"Tuxedo"Monsignori, Perugia, ITALY.

@Tuxedo

There are several reasons.

One is that older MAME releases have bugs that don't get fixed because they were fixed years ago.
Another is that as the older MAME releases age, the ROMs get harder and harder to find.
Another reason is the accuracy is improved in newer releases.
Another is that more ROMs are supported, some of which are quite playable.

You have to remember: not everyone is using a Sam440. If we only ever compile stuff for the Sam and not for the power machines like the X1000, then what's the point in having an X1000? The X1000 is quite fast enough to run MAME and with OpenGL support it could be quite a capable machine for it, because of its RAM speed.

And lastly: why not?
Now I've worked out what needs to be changed, I can set a new version of MAME compiling five minutes after downloading it. It takes a heck of a lot more to do a complete port.

@Spirantho

well...
I played mame 0.37 so much times and I dont found so much problem as you say honeslty(plz write some examples)...

Download(via torrent) all the mame4all rom set was quite easy and fast...I do it in half a day...

The acuracy of mame 0.37 was really enough for me...what do you need exactly?

And, also, plz tell me some roms that newest amme support that was playable on our obsolete hw (maybe only x1000 was sometimes enough for that new roms/mame)

ANd remember...there was really MUCH Sam440 users than x1000(at least 1/20 I think)

TO MODERATORS: sorry I've misswrite my poll so pls changfe the title as the first line of the poll, I forgot to add the title ad so the first line was the title now...

_________________
Simone"Tuxedo"Monsignori, Perugia, ITALY.

@Tuxedo

Quote:

TO MODERATORS: sorry I've misswrite my poll so pls changfe the title as the first line of the poll, I forgot to add the title ad so the first line was the title now...

I don't see anything wrong with the title. What do you want it changed to?

_________________
Moxee
AmigaOne X1000
AmigaOne XE G4
I'd agree with you, but then we'd both be wrong.

@Moxee

The title nave to bè the first line of the poll...
I forgot to write the title it can be somethung like: "What Tyler of MAME do. you like to nave on AmigaOS?"

Sorry for the problem!

_________________
Simone"Tuxedo"Monsignori, Perugia, ITALY.

@Tuxedo

I don't think I have the ability to edit the title of the Poll. I only see the ability to edit the title of the thread.

If you actually mean the title of the thread, then you can also do that edit because you originated the thread.

I'll ask other staff if it is possible to edit the title of the Poll.

_________________
Moxee
AmigaOne X1000
AmigaOne XE G4
I'd agree with you, but then we'd both be wrong.

@Spirantho

Quote:

Spirantho wrote: The X1000 is quite fast enough to run MAME and with OpenGL support it could be quite a capable machine for it, because of its RAM speed.

MAME doesn't benefit from OpenGL at all. except maybe on systems on which "drawing pixels to screen" is significantly slower.

If the system can handle it properly, I'd say it's always faster to draw directly to graphics ram, and let overlay (or same feature with another name) handle the scaling.

Also, all 3D in all games are done by emulating the hardware in question, you cannot simply "drop in" OpenGL.

@Jupp3

OpenGL is used by SDLMAME for its display scaling.

On my 600MHz Sam, with software renderer, space invaders runs at 33% with a larger screen size. With my first OpenGL build, it runs at over 100%.

That's an unusual case, but believe me it can help a lot.

@moxee

Hank you for reply

@Spirantho

The OpenGL only helps. In screen resize(like overlay in video playback) the emulation Speed was affected for example by using 8 bit instead of 16 bit to draw the video...


edit:miiswrite from cellphone...

Last edited by Tuxedo on 07-Mar-2013 at 07:36 AM.
Last edited by Tuxedo on 07-Mar-2013 at 07:36 AM.

_________________
Simone"Tuxedo"Monsignori, Perugia, ITALY.

@Tuxedo

It's true that on a faster system, using OpenGL will make less difference.... but it will always be faster than any other method I reckon.
With an overlay, you can't just write to the video memory and expect it to be the same speed as writing to main memory, certainly not if it's a pixel at a time! MAME would have to render to an off-screen texture anyway because of the amount of pixel operations.

Overlay is pretty much obsolete these days anyway as it's been replaced by render-to-texture methods... using OpenGL. Video cards are optimised these days for texture upload and rendering.

For the record, I have no problem with your porting MAME4All if you want to - just saying I don't have the time to do it. And personally, if I can play games like Ghouls n Ghosts without problem, then I'm happy - whatever version number it is. :)

@Spirantho

Quote:

With an overlay, you can't just write to the video memory and expect it to be the same speed as writing to main memory, certainly not if it's a pixel at a time! MAME would have to render to an off-screen texture anyway because of the amount of pixel operations.

MAME blitter renders the whole frame at a time, and is very inefficient at that, by the way.
By optimizing it, i can write to video memory at the maximum allowed bus speed, be it overlay or not. It would be hard to make it faster than that (except by a dma transfer if the system/machine allows it). And no, OpenGL can't really beat that due to setup time for uploading stuff (i actually tried that for UAE once for fun, and overlay proved to be much faster).

Overlay might be obsolete, but it still beats OpenGL anytime in that regard.

Last edited by Fab on 07-Mar-2013 at 09:03 AM.

@Fab

Thanks for the input! It would be very interesting to see a direct comparison between overlay and OpenGL. Overlay has the difficulty of having to convert to YUV, but OpenGL has the extra overhead of rendering.

Why does the setup-time matter, though? It should only be done once on creating the texture (which is what MAME OGL does) - all it does after that is just shove the texture into the graphics card memory, as the parameters are the same.
From what I can see, MAME sets up a frame for the main emulated screen, and then every frame uploads the texture to that frame. It shouldn't need to set up anything..?

That said, your knowledge of OpenGL is a lot better than mine. :)

@Spirantho

Actually, overlay doesn't require YUV conversion (radeon 9xxx serie has RGB16 pixel format). YV12 would only take 12bits per pixel instead of 16bits for RGB16, but this advantage would be killed by the conversion, i believe. So currently, overlay output is really as fast as direct vmem writing, which is why it can't be much faster than that.

As for OpenGL, i don't know it a lot, but the fact is there's an extra step, which might be more or less important depending on implementations/systems. The main advantage of using OpenGL is more about the additional effects you could apply (especially with shaders), or the fact it's non exclusive.

Last edited by Fab on 07-Mar-2013 at 10:29 AM.

@Spirantho

Quote:

Spirantho wrote: @Jupp3 OpenGL is used by SDLMAME for its display scaling. On my 600MHz Sam, with software renderer, space invaders runs at 33% with a larger screen size. With my first OpenGL build, it runs at over 100%. That's an unusual case, but believe me it can help a lot.

What I meant to say, MAME itself doesn't benefit from OpenGL at all. It just "draws pixels to a surface" and that's about it. It's up to the MAME port on whatever platform you are running, what / how to do with those pixels.

If some MAME port lacks overlay, then it might well be "less heavy" to draw it with OpenGL.

I haven't looked at the code, but I'd guess it's something like:
1)MAME draws screen to an array in RAM.
2)MAME port uploads the pixel data from the array to a texture in graphics ram (this might include pixel format conversion)
3)MAME port draws a fullscreen quad with the texture, that was just uploaded.

Repeat for next frame.

I just can't help the feeling about OpenGL being "the wrong tool" for this. If someone ever started writing a 3D accelerated replacements for various 3D hardware emulation that MAME has (which, of course, makes it "inexact", which is againist what MAME is done for), then it should be an obvious choice. Of course this would be far from an easy task, and probably wouldn't get rid of all 3D hardware emulation (remember that MAME runs compiled code, it's just not possible to modify all games to use OpenGL directly) but something, that will replace code for drawing triangles with an OpenGL equivalent wouldn't be 100% unrealistic.

@Jupp3

Quote:

1)MAME draws screen to an array in RAM. 2)MAME port uploads the pixel data from the array to a texture in graphics ram (this might include pixel format conversion)

Actually, MAME ultimately copies its bitmap to a pointer that can be allocated by the port itself, which in my case is obviously a video address for maximal efficiency (the display is triple-buffered to avoid horrible raster split effects :)).

The problem is MAME is seriously inefficient with its portable copy loop, so i had to modify all this "portable code" to be 4 time faster. ;)

@Fab

Quote:

Fab wrote: Actually, MAME ultimately copies its bitmap to a pointer that can be allocated by the port itself, which in my case is obviously a video address for maximal efficiency (the display is triple-buffered to avoid horrible raster split effects :)).

Well, my point was that with OpenGL (at least "what we currently have") it must be done more or less like that. Pass pointer to glTex(Sub)Image2D(), and it will do the copy. Of course you can update in smaller areas, but that's generally MUCH slower.

Quote:

The problem is MAME is seriously inefficient with its portable copy loop, so i had to modify all this "portable code" to be 4 time faster. ;)

Well lucky for everyone else, the code is public for everyone to borrow

Maybe even port the whole thing. Disabling MUI GUI is probably trivial, don't know how many other "MorphOS specific things" there are.

(Yes, MUI is not MorphOS specific, but perhaps used in a different way from the older versions)

There are definite advantages to a properly Amiga-ised version, to be sure. The only reason I don't is because of lack of time, if someone else wants to have a crack at it I'm quite willing to help. :)
My main reason for compiling (I hesitate to use the word "porting") SDLMAME for the Amiga is just because it was there, and didn't take long to do. I wanted to be able to run the latest version of MAME so we're up to date with the rest of the world.

There are still significant improvements to be made if someone wants a go at it - but the problem then is that you need a proper maintainer if you want to stay up-to-date, as the MAME code changes quite often.

This way, someone else does the hard work for me. :)

Incidentally, I don't believe MAME intends to use any 3D hardware at all for its own renderings of 3D games. OpenGL currently is strictly for 2D acceleration at the moment.

@Tuxedo

Quote:

Hank you for reply

Site Admins say it is not possible to edit the subject of polls which are member started. Only the Main Site polls are.

Sorry it took a few days to respond back to you, but they were trying to see if it was possible.

If it is any consolation, I think the subject is fine as it is.

_________________
Moxee
AmigaOne X1000
AmigaOne XE G4
I'd agree with you, but then we'd both be wrong.

@Moxee

thank you for telling me the problem to change the poll...
I think that the first line was important to define the poll results...maybe in future I will made a new poll :)

_________________
Simone"Tuxedo"Monsignori, Perugia, ITALY.

@Tuxedo

Sure, and if you do just point out that this poll was faulty, in error, or something similar and make a link to this thread so folks know what you mean. You don't want members thinking you are being repetitious. Then let me know so we can lock this thread with a link to the corrected poll thread.

_________________
Moxee
AmigaOne X1000
AmigaOne XE G4
I'd agree with you, but then we'd both be wrong.