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Atari Jaguar VS Sega Saturn


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#251 Gorf OFFLINE  

Gorf

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Posted Sun Sep 9, 2007 1:48 PM

That 32X demo has to be a fake, I know there's no game play or music, but come one. The Saturn was barely able to do that.
But I don't know anything about programming...its just that from what I've seen...come on, that was probably a Saturn demo at best. :)


No its real and impressive for what the 32X is. Who ever did the demo has talent though that's for sure.

Also, Gorf, you complain about not having enough time on your hands to program the Jaguar...well quit writing these 10 page arguments on the forum and then you should have plenty of time to write more awesome games!!!
LOL, just kidding man! ;) :) Thought that would be a funny joke. :)


I'd laugh if I did not know the agony it is to code the Jaguar with the current tools.

Scatologic took eight years in there spare time. Gorf 3D and Plus would have been
done already if we did what most everyone else did however, which was just be satisfied
with what was available. We decided to eliminate the 68k altogether in our games where
more power is a must.

The 'Surrounded!'™ demo which is something i've written on other platforms took me a long
time on the jag in comparison.....When I coded 'Surrounded!'™ on the PC, It took me 3 or 4
hours roughly. There is really nothing heavy hitting going on there...its 6 sided (3D) simon. A proof
of concept more than anything. On the Jaguar I took me a week and a half just to get the demo
running in main. I FIRST ported it over to the 68k as the PC version was in C code but it ran like
a snail.

Im trying to find that code again so I can show everyone a 68k vs GPU local vs GPU main
comparison using 'Surrounded!'™.

I can write a sites worth of post and have plenty of time to code....in fact...Im typing this
as I code the contract work I have.....I can walk and chew gum at the same time. :D
I dont have time for Jag right now because of the contract work. I do sneak a little in here
and there from time to time...very little but anything to keep sharp.

As much as I love the contract stuff Im doing....trust me....I have more fun coding my Jaguar
for nothing, getting a US RDA beatdown on the forums and all!!! I want to get back to the
sucker more than you want me to. However, I have to eat at least once a day... ;)

#252 superjudge3 OFFLINE  

superjudge3

    Moonsweeper

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Posted Sun Sep 9, 2007 10:21 PM

Hehehe, I know man. Just thought I'd change the subject so we could have a laugh or two instead of everyone trying to pick a fight with you...it's amazing how many people would rather get on a message forum and argue about a 14-year old system!

Let's just enjoy the Jaguar and get on with it! :)

Good luck to you!

#253 Gorf OFFLINE  

Gorf

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Posted Mon Sep 10, 2007 5:34 AM

Hehehe, I know man. Just thought I'd change the subject so we could have a laugh or two instead of everyone trying to pick a fight with you...it's amazing how many people would rather get on a message forum and argue about a 14-year old system!

Let's just enjoy the Jaguar and get on with it! :)

Good luck to you!


Thanks, as the MC says...."You'll need it!"

#254 Atari_Owl OFFLINE  

Atari_Owl

    Stargunner

  • 1,010 posts

Posted Tue Sep 11, 2007 9:17 AM

Again...instead of shooting off your mouth, being clearly unknowledgable about the Jaguar, you should read.
The docs say CLEARLY that there are issues with the jump instructions in main ram that make running code
with jumps unreliable. they recommende against it and NO one bothered to try to find a work around, obviously.
That is why everyone either overused the 68k or inefficiently flipped code in and out of the local.


That sounds like a pretty serious design flaw.

It also says jumping between main and local is not reliable either. This is a completely incorrect statement. Go
and download Surrounded! Demo I posted for living proof that this is no longer true. I can not only run in main
but jump back and forth to and from local and main with NO assitance from any other processor.


Okay Gorf, once again I never said that this wasn't possible. Why do you keep arguing with me about things I'm not even saying?

This demo started out running on the 68k for game AI and got about 15- 20 fps. I moved that over to the GPU
using code flips to the local and got a significant increase in frame rate 20-30 FPS.

I then discovered the main ram jump workaround and moved the GPU code of the AI in main ram. It again
increase noticably in frame rate and allowed me to obtain 30-60 fps out of a demo that once ran only 15 at
best then 20- 30 with the code flips. The GPU will never run as fast in main but it will run fast enough. Alot faster
than the 68k and is pretty much my only claim on the subject.


The 68k is a very slow processor, that's all there really is to say about that (I wish people pushing Genesis over SNES would start realizing this).

When I say I want benchmarks what I'm actually interested is in how code (that does nothing external, no data memory accesses) that is purely in main RAM compares to code that is purely in the SRAM.


I guess i'm a little late to the discussion.
This is how i addressed the speed issue twice before.

Again to restat and confirm Gorf's position:. Atari did not tell people not to run RISC code out of main because it was slow.. as was implied in the thread.. but because they believed it was not possible to run RISC code from main due to the problems with JR and JUMP. They were wrong its perfectly possible to jump within Main and between Main & Local without intervention from any other processor. There can be a fairly large hit on speed though depending on the BUS load and the nature of the code executed.



This is what i said then:

Gorf is obviously and justifiably proud and pleased about the development, i tend to be more cautious and do not see it as quite the panacea he does.
In my own coding i've found the speed of GPU running from main to be highly dependent on load on the main BUS (eg. from the blitter) with speeds typically in the range of 20-90% of the speed of the same code running from GPU local ram. (By which i mean 5 times slower to almost the same speed).
It would therefore be foolish for example to put a tight, commonly called routine in main ram, its far better called in local.


Now lets take a look at the 20% speed. Thats a pretty large cut in speed.. faster than the 68k? For sure, but a lot slower than local.
Is it worth taking the 68k off the bus and running in GPU from main instead with the 68k STOPped? Without a doubt!

[lets look at it from a maths point of view.. i believe the speed of the ST 68k at 8MHz was reported as being very roughly about 1MIP... Therefore at 13.3MHz this should be about 1.65MIPS... in theory the GPU can reach 26.6MIPS, in practice this tends to be more like 17MIPS in other words 10x the speed of the 68k, even if we run at 20% its still twice as fast as the 68k and thats not even taking into account the effects on BUS]

Is it worth running from main instead of paging code to/from the GPU local? Ummmmmmm.... Sometimes yes, sometimes no. Its a hard question to answer and depends on a great many factors including the BUS load and the code in question.


Edited by Atari_Owl, Tue Sep 11, 2007 9:41 AM.


#255 Gorf OFFLINE  

Gorf

    River Patroller

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Posted Tue Sep 11, 2007 9:56 AM

Again...instead of shooting off your mouth, being clearly unknowledgable about the Jaguar, you should read.
The docs say CLEARLY that there are issues with the jump instructions in main ram that make running code
with jumps unreliable. they recommende against it and NO one bothered to try to find a work around, obviously.
That is why everyone either overused the 68k or inefficiently flipped code in and out of the local.


That sounds like a pretty serious design flaw.

It also says jumping between main and local is not reliable either. This is a completely incorrect statement. Go
and download Surrounded! Demo I posted for living proof that this is no longer true. I can not only run in main
but jump back and forth to and from local and main with NO assitance from any other processor.


Okay Gorf, once again I never said that this wasn't possible. Why do you keep arguing with me about things I'm not even saying?

This demo started out running on the 68k for game AI and got about 15- 20 fps. I moved that over to the GPU
using code flips to the local and got a significant increase in frame rate 20-30 FPS.

I then discovered the main ram jump workaround and moved the GPU code of the AI in main ram. It again
increase noticably in frame rate and allowed me to obtain 30-60 fps out of a demo that once ran only 15 at
best then 20- 30 with the code flips. The GPU will never run as fast in main but it will run fast enough. Alot faster
than the 68k and is pretty much my only claim on the subject.


The 68k is a very slow processor, that's all there really is to say about that (I wish people pushing Genesis over SNES would start realizing this).

When I say I want benchmarks what I'm actually interested is in how code (that does nothing external, no data memory accesses) that is purely in main RAM compares to code that is purely in the SRAM.


I guess i'm a little late to the discussion.
This is how i addressed the speed issue twice before.

Again to restat and confirm Gorf's position:. Atari did not tell people not to run RISC code out of main because it was slow.. as was implied in the thread.. but because they believed it was not possible to run RISC code from main due to the problems with JR and JUMP. They were wrong its perfectly possible to jump within Main and between Main & Local without intervention from any other processor. There can be a fairly large hit on speed though depending on the BUS load and the nature of the code executed.



This is what i said then:

Gorf is obviously and justifiably proud and pleased about the development, i tend to be more cautious and do not see it as quite the panacea he does.
In my own coding i've found the speed of GPU running from main to be highly dependent on load on the main BUS (eg. from the blitter) with speeds typically in the range of 20-90% of the speed of the same code running from GPU local ram. (By which i mean 5 times slower to almost the same speed).
It would therefore be foolish for example to put a tight, commonly called routine in main ram, its far better called in local.


Now lets take a look at the 20% speed. Thats a pretty large cut in speed.. faster than the 68k? For sure, but a lot slower than local.
Is it worth taking the 68k off the bus and running in GPU from main instead with the 68k STOPped? Without a doubt!

[lets look at it from a maths point of view.. i believe the speed of the ST 68k at 8MHz was reported as being very roughly about 1MIP... Therefore at 13.3MHz this should be about 1.65MIPS... in theory the GPU can reach 26.6MIPS, in practice this tends to be more like 17MIPS in other words 10x the speed of the 68k, even if we run at 20% its still twice as fast as the 68k and thats not even taking into account the effects on BUS]

Is it worth running from main instead of paging code to/from the GPU local? Ummmmmmm.... Sometimes yes, sometimes no. Its a hard question to answer and depends on a great many factors including the BUS load and the code in question.



Good job bud! But Exophase realizes things about the Jaguar now that he admitted not knowing before hand.
Then again, beside you and I , who else knows....shoot me an email or get on the im when you have a chance
if you would...I need to chat with you...catch up on a few things...give you some hopeful news as well.

:)

#256 Atari_Owl OFFLINE  

Atari_Owl

    Stargunner

  • 1,010 posts

Posted Tue Sep 11, 2007 10:03 AM

Good job bud! But Exophase realizes things about the Jaguar now that he admitted not knowing before hand.
Then again, beside you and I , who else knows....shoot me an email or get on the im when you have a chance
if you would...I need to chat with you...catch up on a few things...give you some hopeful news as well.

:)


Will do.. i've been a little out of the loop recently.
Looking forward to the news :)

CHeers :)

#257 Gorf OFFLINE  

Gorf

    River Patroller

  • 4,633 posts

Posted Tue Sep 11, 2007 10:49 AM

Good job bud! But Exophase realizes things about the Jaguar now that he admitted not knowing before hand.
Then again, beside you and I , who else knows....shoot me an email or get on the im when you have a chance
if you would...I need to chat with you...catch up on a few things...give you some hopeful news as well.

:)


Will do.. i've been a little out of the loop recently.
Looking forward to the news :)

CHeers :)


Cool. See you then. :)




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