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Old 25 February 2020, 14:37   #101
VladR
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Originally Posted by coder76 View Post
Not to mention that 68030 boards are the most common today (40-50 MHz), because they are enough to play most games and to use workbench, and also the most compatible with old software. And they are still manufactured today in the form of ACA accelerators. Also way cheaper than 68060 boards. Some 68040/68060 boards also have problems with chip ram access speed (giving less than 7 MB/sec), which is vital for CPU-drawn graphics speed.
Wait, what?

A 50 MHz 030? When did that happen?!?

I swear I thought 030s were only 16 MHz.
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Old 25 February 2020, 14:45   #102
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Wait, what?

A 50 MHz 030? When did that happen?!?

I swear I thought 030s were only 16 MHz.
The Blizzard 1230-IV used a 50MHz '030 - I had one and it was sweeeeet as hell.
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Old 25 February 2020, 15:21   #103
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Originally Posted by grond View Post
Funny how considering lowering the minimum specs to 060-based systems then led to people suggesting including 040 systems (a Vampire is ten times the speed of an 040...)
Is the 10x factor a real MIPS benchmark or just an ideal scenario where both CPU pipes are operating at 100% throughput?
I'm going to burn through it anyway by locking the fps and using 32-bit (well at least I hope I can have 32-bit - I was supposed to have benchmarks done at this point yet still waiting for opportunity to upload stuff).

Either way, I'm currently using 040 as a compiler target, so it technically should run on real 040, even if at questionable fps...

Point is, if I am going to be creating a separate detail of art assets for 060, why not make them slightly less detailed so it runs on 040? And the 060 will get slightly higher fps that way.

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Originally Posted by grond View Post
and now we are even getting 030s into the mix.
Well, if the 030 is at 50 MHz, surely it's fast enough, I would assume. For some version of the art assets, that is.
I just checked the Motorola 040 CPU doc and 040 has a 6-stage pipeline with most ops between registers at around 2-3 cycles. No idea yet on RAM access speed.

Would have to check 030 doc on its execution speed. I don't recall if the transition to superscalar happened already with 030 or if it was 040.
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Originally Posted by grond View Post
It is only a matter of time until someone will argue that plain 68000 systems are the most common Amiga systems and that those should be supported, too...
I could be persuaded to code A500 renderer if, say, 250 people pre-ordered it. Which I doubt.
But that's far down the line.
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Old 25 February 2020, 15:46   #104
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But I'd like to see anyway that you push Vampire to the limit (basically, you have exclusive opportunity to do that), and then make degraded versions for 060 and 040 (and 030, if possible).
Yes, it is indeed an exclusive opportunity at this time.

And Vampire will have exclusive art assets (based on my benchmarks).

I'm just not convinced about pushing the performance to the limit is good for player.
On Jaguar I had plenty opportunity to experience the drop from 60 fps to 30 fps with double buffering when real frame rate was around 57 fps.

It's brutal as it's random and only occurs for few frames and then you are back to 60. Tearing would fix that.

However if I locked the framerate to 30 fps, yet never experienced a frame drop, it was infinitely more pleasing experience.

Of course, I can't lock fps on 030-060. The performance differential there is far too great. Hence triple buffering there.
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Old 25 February 2020, 16:26   #105
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Originally Posted by VladR View Post
I could be persuaded to code A500 renderer if, say, 250 people pre-ordered it. Which I doubt.
But that's far down the line.
Interesting.
So how much would you ask for a pre-order (before I say, count me in! )?
I hate distracting you from original goal (that is vampire), but then again, there's my beloved A500 we are talking.

Who knows.... maybe if you have to show some amazing demo, and with proper advertising (facebook, youtube, every amiga forum), maybe you could achieve much higher number then 250.

That's just my blind guess, I am really unsure.
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Old 25 February 2020, 17:13   #106
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Is the 10x factor a real MIPS benchmark or just an ideal scenario where both CPU pipes are operating at 100% throughput?
It's a rough estimate. If you use bitfield instructions, the 080 will be much, much faster than the 10x figure given. Same for other specific code or even 080-exclusive code. If we are talking about standard compiler code, it will often only be like 5x faster than an 040.


Quote:
I'm going to burn through it anyway by locking the fps and using 32-bit (well at least I hope I can have 32-bit - I was supposed to have benchmarks done at this point yet still waiting for opportunity to upload stuff).
With RTG being available via Zorro3, we are talking about 16 MB/s throughput to graphics memory for anything less than a Vampire.


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Point is, if I am going to be creating a separate detail of art assets for 060, why not make them slightly less detailed so it runs on 040? And the 060 will get slightly higher fps that way.
Slightly? The 060 is about 3x faster than the 040. Or rather the 040 is three times slower than the 060.


Quote:
Well, if the 030 is at 50 MHz, surely it's fast enough, I would assume.
The 50 MHz 030 is about the same speed as the 25 MHz 040 for integer. Forget about floating point. Many 030 accelerators don't even have an FPU and it is too slow anyway to be useful for this type of program.


Quote:
No idea yet on RAM access speed.
I think the fastest Amiga turbo cards are reaching the 50 MB/s territory. The Vampire is 600MB/s.


Quote:
I don't recall if the transition to superscalar happened already with 030 or if it was 040.
The only superscalar 68k processors are the 060 and the 080.


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I could be persuaded to code A500 renderer
An A500 is about 300x slower than a Vampire.
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Old 25 February 2020, 17:32   #107
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Originally Posted by d4rk3lf View Post
Interesting.
So how much would you ask for a pre-order (before I say, count me in! )?
I hate distracting you from original goal (that is vampire), but then again, there's my beloved A500 we are talking.

Who knows.... maybe if you have to show some amazing demo, and with proper advertising (facebook, youtube, every amiga forum), maybe you could achieve much higher number then 250.

That's just my blind guess, I am really unsure.
You are not distracting me, don't worry. A500 is a fair question once we descend from 170 MIPS territory down to the ~7 MIPS of 50 MHz 030.

I'm afraid it's also a Catch-22. To get a good frame rate on A500, I would have to spend at least 3-4 months experimenting with various Blitter bitplane approaches till I find out what's fastest for my game. From what I gathered so far, there's at least three major technical approaches to implement. Each one taking 2-3 weeks easily, quite possibly more with debugging Blitter interrupt queues.

And only then the final art assets can be created.

If the Vampire version does well, I could justify burning,say, 4-6 weeks of research time to see what I could get out of A500. Emulator is supposedly cycle perfect there so it's realistic to develop only against emulator.

I also have to consider a very real possibility that if I took pre-orders for A500, I might not come up with something special on A500 even after six months of work. That would suck for everyone.

However, the single greatest advantage of it would be that I would have a 3D engine and game framework that spans the entire range of Amiga - from the slowest A500 , through 68030-68060, up to 512 MB Vampire.

Not sure if that's something appealing to anyone else but me...
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Old 25 February 2020, 17:37   #108
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I do not have a Vampire. Or a 68060. Or even a 68040.
And yet, I'd say: go for the Vampire version and don't compromise. That system deserves a few stellar showcases for it, just as much as others are pushing the A500 or A1200
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Old 25 February 2020, 18:12   #109
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Originally Posted by grond View Post
It's a rough estimate. If you use bitfield instructions, the 080 will be much, much faster than the 10x figure given. Same for other specific code or even 080-exclusive code. If we are talking about standard compiler code, it will often only be like 5x faster than an 040.
By standard compiler code - what exactly do you mean here? I'm coding this in assembler (well, Higgs really, but that's Asm) not C.


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Originally Posted by grond View Post
With RTG being available via Zorro3, we are talking about 16 MB/s throughput to graphics memory for anything less than a Vampire.
16 MB/s somehow sounds quite good at the target resolution and frame rate. A 256x200 framebuffer is 50 KB. A clear plus redraw at 20 fps would consume (50+50)*20=2 MB.
There is still chunky to planar conversion, not sure how much that would take.


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Originally Posted by grond View Post
Slightly? The 060 is about 3x faster than the 040. Or rather the 040 is three times slower than the 060.
Thanks for your patience with me.
So, in this case, it appears 060 would need different art assets and 68040 would need different ones too.
The 3:1 ratio is obviously brutal difference.



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Originally Posted by grond View Post
The 50 MHz 030 is about the same speed as the 25 MHz 040 for integer. Forget about floating point. Many 030 accelerators don't even have an FPU and it is too slow anyway to be useful for this type of program.
Yeah, just found out it's basically high clocked 68000.
But, it's still a significant improvement over A500.



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Originally Posted by grond View Post
I think the fastest Amiga turbo cards are reaching the 50 MB/s territory. The Vampire is 600MB/s.
Well, downgrading to 256 colors should bring the ratio down to 4:1. That should help a lot.

If we target around 20 fps, we have 2.5 MB per frame.
320*200 = 64 KB. That's around 40 times per frame.



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Originally Posted by grond View Post
The only superscalar 68k processors are the 060 and the 080.
Yes. Sorry, I meant multi-stage pipeline. 68040 has a 6-stage pipeline and most common instructions and addressing modes only take a few cycles.
I just downloaded the 030 pdf and from a brief check it appears only a higher clocked version of 68000, with instructions taking great many cycles.



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Originally Posted by grond View Post
An A500 is about 300x slower than a Vampire.
I actually have the best idea on A500's performance from all Amigas, since I spent a lot of time on Jaguar benchmarking 68000's Software rasterizer.
Jaguar has 68000 at 13.3 MHz, so A500 should roughly achieve 50% performance. No idea on performance impact of bitplanes. Theoretically, 4-bit color depth should gain some of that differential back.
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Old 25 February 2020, 18:20   #110
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Originally Posted by VladR View Post
I'm afraid it's also a Catch-22.
Totally got what you're telling.
Once you got playable demo that looks and works awesome, it will be like 70% of the job done.

Btw, you may, or may not know of this game, but it's the most impressive 3D racing I saw on Amiga 500.
And yes.. it goes that speed on real Amiga 500.
[ Show youtube player ]

Vroom is also great for me.

Quote:
Originally Posted by roondar View Post
I do not have a Vampire. Or a 68060. Or even a 68040.
And yet, I'd say: go for the Vampire version and don't compromise. That system deserves a few stellar showcases for it, just as much as others are pushing the A500 or A1200
Completely agreed!
I would love to see him pushing the vampire hardware as further as it can, and only after he releases the game (and hopefully get big success), to start and porting it for 060/040... and why not.. A500.
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Old 25 February 2020, 18:25   #111
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Originally Posted by roondar View Post
I do not have a Vampire. Or a 68060. Or even a 68040.
And yet, I'd say: go for the Vampire version and don't compromise. That system deserves a few stellar showcases for it, just as much as others are pushing the A500 or A1200
Don't worry. I'm not going to butcher Vampire version.

But 90-95% of code will be identical whether it's V4 or 68040-060.

So it's important you guys are patient and are educating me on the incredibly fragmented HW space of the Amiga world.

All those considerations you have been taking for granted last quarter century are a brand new information for me
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Old 25 February 2020, 18:30   #112
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Originally Posted by VladR View Post
By standard compiler code - what exactly do you mean here?
C compiler code that cares little for superscalarity.


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16 MB/s somehow sounds quite good at the target resolution and frame rate. A 256x200 framebuffer is 50 KB. A clear plus redraw at 20 fps would consume (50+50)*20=2 MB.
There is still chunky to planar conversion, not sure how much that would take.
If we are talking about Amiga planar modes, that would be 7 MB/s for AGA and A3000-ECS (32bit buswidth) and 3.5 MB/s for OCS and A500+/A600-ECS (16bit buswidth). For RTG you don't need to do chunky2planar.


Quote:
Yeah, just found out it's basically high clocked 68000.
Don't do the 030 injustice, it was a very fine processor for its time and is much more than a high clocked 68000. For starters, it has a real 32bit ALU while the 68000 only has a 16bit ALU. The biggest problem for you with anything below the 040 will probably be the tiny or non-existent caches.


Quote:
If we target around 20 fps, we have 2.5 MB per frame.
320*200 = 64 KB. That's around 40 times per frame.
With the slower 68k you will only reach those numbers for plain linear copy stuff. For more complex things you will lose too many cycles on actual instruction execution and thus get much less out of the memory.


Quote:
Yes. Sorry, I meant multi-stage pipeline. 68040 has a 6-stage pipeline and most common instructions and addressing modes only take a few cycles.
I just downloaded the 030 pdf and from a brief check it appears only a higher clocked version of 68000, with instructions taking great many cycles.
Ah, yes, the 040 was the first pipelined 68k processor.


Quote:
Jaguar has 68000 at 13.3 MHz, so A500 should roughly achieve 50% performance. No idea on performance impact of bitplanes. Theoretically, 4-bit color depth should gain some of that differential back.
Now we have gone down from truecolour rendering on the Vampire down to 16 colours on an A500...

It would indeed be interesting to see the same game made for this large a span of target platforms.
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Old 25 February 2020, 18:38   #113
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Totally got what you're telling.
Once you got playable demo that looks and works awesome, it will be like 70% of the job done.

Btw, you may, or may not know of this game, but it's the most impressive 3D racing I saw on Amiga 500.
And yes.. it goes that speed on real Amiga 500.
[ Show youtube player ]
I saw Atari ST version but I am glad you posted this link as it describes the problem here very well.
To achieve the same frame rate, I highly doubt my first version would get anywhere near on A500. Hence the 6-month research period (which still doesn't guarantee it).

Is the game running in full screen? The vid has some boundaries around the screen so not sure. Is that 256*200?
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Old 26 February 2020, 11:46   #114
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Is the game running in full screen? The vid has some boundaries around the screen so not sure. Is that 256*200?
Here's the screenshot from my real Amiga 500.
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Old 26 February 2020, 14:19   #115
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Originally Posted by d4rk3lf View Post
Here's the screenshot from my real Amiga 500.
looks like 320x200
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Old 26 February 2020, 16:30   #116
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Here's the screenshot from my real Amiga 500.
Proper full screen. That's unfortunate
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Old 26 February 2020, 16:52   #117
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Proper full screen
Well, about one third is filled with static information...
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Old 26 February 2020, 17:50   #118
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Well, about one third is filled with static information...
Don't know if it counts, but intro is full screen showing the engine capabilities.

I will try to research more about engine, it would be amazing if we could get a source code of it. I mean, not amazing for me, because I know nothing about coding, but coders could learn a lot from it, I guess.
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Old 26 February 2020, 18:06   #119
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Don't know if it counts, but intro is full screen showing the engine capabilities.
Well, it is an intro. We can only guess how much of it is precomputed. There is no need for any type of collision checks, AI or whatever. It also seems there are less objects in the intro than in the game.
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Old 26 February 2020, 21:18   #120
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Well, about one third is filled with static information...
True. That always helps. Scanline traversal is expensive and with triangles you pay the cost twice per each scanline (left and right triangle of a quad). But, perhaps they draw road as quads so each scanline gets processed just once.

They do have arches that cross top screen edge, which is the most expensive clipping cost out of all screen edges.

It's still a very respectable frame rate. I doubt they fully clear the frame buffer each frame.
Probably have an effective way of figuring out how much has to be cleared.
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