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Old 30 July 2009, 20:16   #221
Ian
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Originally Posted by Goldrunner View Post
Instead we have non stop comaprisons to show how great the Amiga was. Even when faced with great machines like the Acorn Archimedes, Atari Falcon, an even the Atari STE, they simply claim, yeah but they didn't well so that is that.
Who cares PCs > all of them.
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Old 30 July 2009, 20:24   #222
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When toned down, the game loses his qualities.... Look what happened with most coin-op conversions ;
When it comes to coin-op conversions the most important thing would be that it does not losing the speed of the original... gameplay first then graphics and sound.
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Old 30 July 2009, 20:36   #223
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PCs > all of them
Yeah greater at sucking and crashing and using ridiculous quantities of memory/clock cycles while idle.
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Old 30 July 2009, 20:40   #224
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Sorry Goldrunner, it even got worse after you left... Come back!
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Old 30 July 2009, 20:55   #225
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Originally Posted by Si-Pie View Post
Hi Frank yep thanx for that and yep I agree that DMA contention slows the blitter down for 4 and 5 plane PAL screen modes.
Hello. Yeah that was me
It actually slows down for every plane you switch on the Amiga.
It's still much more efficient than the 68k.

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Originally Posted by Si-Pie View Post
I think that is what I was pointing out when I posted that quote from the Amiga Hardware Reference Manual about bit-plane DMA stealing cycles from the 68000 during display. I personally think the STE was what the ST should of been but Atari just released it too late.
Indeed. I still like the machine though even if it was too late.

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I have seen another post from you by the way on another forum but cant remember which one. You do some calculations on the Amiga Blitter and STE Blitter and gave quite abit of info on them.
Yeah that was me I'm a huge Amiga/ST geek. It saddens me when the STE or the Amiga gets a bashing from people who basically don't know the machines. I've been trying to prod a certain person into reading the HRM but sadly to no avail. It's a shame since once read and understood people can really see just how *beautiful* the Amiga was. Incidentally if people want to know what the blitter can and can't do on the STE the manual is online. It's vastly underrated.

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Ive read alot of posts on here from people who seem to be knocking both machines. I dont think almost any person who was an ST fan from back then deny that the Amiga had a hardware advantage over the ST but I personally think that just because a machine isnt best on the market doesnt mean it shouldnt have fans or be liked. I owned an Amiga and was and still am a big Amiga fan but I still respected the ST and the contribution it had in the market! These are machines that belong to a great era in computing and hardware differences aside both should be remembered as great machines.
Yup. There's nothing remotely like them left. The ST was a nice machine* and the Amiga was lovely.

Frank

*Don't take my word for it. Google for Jay Miner's comment on the ST.
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Old 30 July 2009, 22:08   #226
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Originally Posted by dlfrsilver

Well, the problem here is that the acorn was an english only machine.
It was never exported outside England. I never seen one, never seen games running on it.
There are some good Acorn Archimedes emulators, such as the one called Red Squirrel (because of the Acorn logo) or Arculator if you would like to experience what it was like. RiscOS is quite different to most other OSs most people have used and quite advanced. Although it has its oddities that are inherent from the BBC Micro era.

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Originally Posted by Photon

their BASICs rocked throughout all their platforms

the games for Archimedes were pretty bad, Zarch and not much more
BBC Basic was far ahead of any other. It was a great language. And in fact the whole BBC range of computers were far ahead of any other at the time as well. I will even go as far as to say the Archimedes was a superior hardware to the Amiga!

As for games. Take another look. It had a lot of the same releases as the Amiga and ST. Take a look here for some screenshots. Doom is also an especially good port, and more capable than the Amiga's version, thanks to the Arch's RISC based 32bit CPU.

If anyone is interested in seeing what the hardware spec of the Archimedes was you can see one of the later popular model's specs here.

As you will notice the 256 colours on screen from a palette of 4096, 8 channel stereo sound, with 8 voices at 42 kJz or 4 as 83 kHz, 46 built in screen resolutions plus freely programmable additional ones possible, 4MB ram, 12MHz RISC CPU (8 MIPS), native HDD support etc made it a pretty impressive system.

Such a shame it was never a commercial success outside of UK schools.
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Old 30 July 2009, 22:58   #227
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As you will notice the 256 colours on screen from a palette of 4096, 8 channel stereo sound, with 8 voices at 42 kJz or 4 as 83 kHz, 46 built in screen resolutions plus freely programmable additional ones possible, 4MB ram, 12MHz RISC CPU (8 MIPS), native HDD support etc made it a pretty impressive system. Such a shame it was never a commercial success outside of UK schools.
I would have loved to work with the RISC CPU, barrel shifter (just like the Amiga's blitter), 1 clock per instruction (68000 was 4 minimum, more like 8), 16 general purpose registers (or was it 32, I forget). I've got a book somewhere on ARM assembly, never used it though .

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had an Atari with a monochrome monitor to run a $2500 program called Arkey which he used to design buildings. The company he worked/workes for chose this program because it was cheaper than the alternative while doing everything they needed to do with it...
Was it available for the Amiga though?

But seriously, I agree they were all general purpose computers to an extent - although only because they had a keyboard. Of all the 8-bit machines I would say only the BBC Micro was truly general purpose.

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Well well, It seems we have on board Richard Costello The good coder behind Golden Axe port

So pal, one end for all, which is the most accurate port of Golden Axe between the amiga port and the megadrive port ? Since you coded it on amiga, i guess you can hint us ?
Guilty

Oooo got to think now ... I coded the "chop chop" game that ran in between levels on the Megadrive version, so the same logic code was used in the Amiga version for that. Megadrive had loads of hardware sprites which was ideal for a game like Golden Axe along with a hardware character based scrolling background plus lots of buttons. I THINK the Amiga version was actually a close port of the ST version although I probably used the blitter to speed things up. I would need to wade into the source to work it out.

As for which was the closest to the coin-op, back then coin-op conversions were "watch the screen and make this computer do it" so no access to code or graphics from the coin-op at all. So all game logic was created from scratch, I remember I preferred playing the Amiga version but the disc access was irritating.

But back to the topic

Last edited by Graham Humphrey; 30 July 2009 at 23:59. Reason: Back-to-back posts merged
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Old 30 July 2009, 23:27   #228
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Yeah greater at sucking and crashing and using ridiculous quantities of memory/clock cycles while idle.
Guessing someone doesn't have a recent/decent PC able to reduce everything when it's idle.
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Old 30 July 2009, 23:36   #229
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Nice to meet you Ric - Golden Axe is probably the finest Amiga Arcade conversions
: in fact some think this version is better than the Sega version
What happend to Golden Axe 2-3
Nice to meet you too & thanks

I didn't even know there was a Golden Axe 2-3

As far as the Amiga/ST goes I was also guilty of Gauntlet II, Hotrod, T2 (sorry), Motorhead (sorry squared) then just Amiga MKI, MKII and Primal Rage.

It was MKI that used a combination of hardware sprites and blitter for one of the characters, which caused the timing issues. I gave up for MKII and just used the blitter as I recall. My A500 rang it fine, but the testers at Probe kept getting screen issues which I couldnt replicate until I went down to London and saw it for myself. Only way to solve it was to stop using one pair of sprites or reduce the screen width by 16 pix. What has happening was a 16 colour sprite kept loosing 2 of its planes, so dropping to 4 colour because there was no DMA space for it.

The soft-sprite engine in these games was based on 16 x 16 pixel "tiles" which were all compressed. The 68000 would decompress a character into a buffer and the blitter would cookie cut it onto the screen generating a mask on the fly whilst the 68K decompressed the next tile etc. Nice parallel processing when the 68K could scrounge a clock cycle or 2 from the blitter.

The Amiga was very nice, you could also do LOADS of voodoo with the floppy disc controller too. ST was boring by comparison.
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Old 30 July 2009, 23:37   #230
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Guessing someone doesn't have a recent/decent PC able to reduce everything when it's idle.
I'm typing on a Mac Book Pro, once you've gone Mac there's no turning back
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Old 30 July 2009, 23:56   #231
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I will even go as far as to say the Archimedes was a superior hardware to the Amiga!
Archimedes (of A3000 generation, which is what all games were written for) has exactly 3 things over the Amiga :

- ARM CPU
- Decent memory bandwidth (25.6mb/sec - though video DMA grabs a large chunk of this)
- Chunky 256 colour mode

The rest is inferior. I've done some coding for the Arc recently and I've not at all enjoyed the fixed palette in 256 colour mode, the CPU driven 8 voice sound (ever wonder why no games used all 8 voices?), the hardware scrolling that's only accurate to every _other_ pixel and that you're not supposed to use anyway, and the flakiness of RiscOS in general.
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Old 30 July 2009, 23:58   #232
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Please please please can we keep this thread somewhere vaguely close to the topic at hand?
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Old 31 July 2009, 00:28   #233
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Filled/wireframe 3D games should always run faster on Amiga over ST and yes that includes Elite 2!

Yes the Amigas custom hardware was primarily designed for 2d graphics but Jay Miner loved those 3D flight simulators! That is why the Amigas Blitter chip can draw polygons so the CPU dosen't have to! The Amiga Blitter can draw lines at 1 million pixels a second and fill them at 16 million pixels a second in parallel to the CPU calculating the next set of coordinates. Elite 2 uses curved lines which the Blitter dosen't support but if it had used the Amigas fill mode it would run faster than the ST version.

I remember Braben saying he didn't use the Blitter in an interview for an Amiga magazine.The only reason it ran faster on an ST is because it was a direct port. I bet the sound is crap though compared to the Amiga version?

Did everyone not know the blitter had this ability ?

I don't know a lot about the STE blitter but the Amiga Blitter has 4 DMA channels which can be combined in 256 different ways, it's pipelined, has 2 barrel shifters, has hardware line drawing and polygon filling. How does the STE Blitter compare to this as I know it was a lot newer than the Amiga 1985 Blitter?
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Old 31 July 2009, 00:39   #234
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Nice to meet you too & thanks

I didn't even know there was a Golden Axe 2-3

As far as the Amiga/ST goes I was also guilty of Gauntlet II, Hotrod, T2 (sorry), Motorhead (sorry squared) then just Amiga MKI, MKII and Primal Rage.

It was MKI that used a combination of hardware sprites and blitter for one of the characters, which caused the timing issues. I gave up for MKII and just used the blitter as I recall. My A500 rang it fine, but the testers at Probe kept getting screen issues which I couldnt replicate until I went down to London and saw it for myself. Only way to solve it was to stop using one pair of sprites or reduce the screen width by 16 pix. What has happening was a 16 colour sprite kept loosing 2 of its planes, so dropping to 4 colour because there was no DMA space for it.

The soft-sprite engine in these games was based on 16 x 16 pixel "tiles" which were all compressed. The 68000 would decompress a character into a buffer and the blitter would cookie cut it onto the screen generating a mask on the fly whilst the 68K decompressed the next tile etc. Nice parallel processing when the 68K could scrounge a clock cycle or 2 from the blitter.

The Amiga was very nice, you could also do LOADS of voodoo with the floppy disc controller too. ST was boring by comparison.
Unbelievable they wouldn't give you the graphic/sound files at least. Surley paying for a license they should have given you the graphics files ? Most those old arcade machines used the 68000 so the source code would have been very handy.

I really liked your conversion of Golden Axe. I'm sure there were strict deadlines and with no support from Sega it didn't make things easy. With a bit more more time how much better do think you could have made it ? I'm sure you could have found a way to make use of hardware sprites. Just look how Shadow of the Beast used them.

What did your Mortal Kombat team make of Elfmania ?
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Old 31 July 2009, 01:12   #235
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Filled/wireframe 3D games should always run faster on Amiga over ST and yes that includes Elite 2!


I don't know a lot about the STE blitter but the Amiga Blitter has 4 DMA channels which can be combined in 256 different ways, it's pipelined, has 2 barrel shifters, has hardware line drawing and polygon filling. How does the STE Blitter compare to this as I know it was a lot newer than the Amiga 1985 Blitter?
The Atari blitter lacks hardware line draw and area fill. It's a 2 src blitter where one of the sources is also the destination. There are 16 ways of combining source and destination. As the destination is also a source this includes modes like ~dst & ~src. Sadly this means that masking sprites takes two passes.

Like the amiga it has signed src y/dst y modulos. Unlike the Amiga it has srcx and dstx signed modulos. Not exactly a feature but something required for interleaved ST video format.

It has 16 words of on chip RAM (Halftone) which can be used to apply a pattern for every word on a line. They can be anded with the the src data. This can also be used as an indirect addressing mode. The four bits shifted out of the src word act as a look up onto this data. There are three end masks (first/middle/end) which affect which bits are written to on a line. The Amiga IIRC masks off bits from the source (A I think..). Combine both and it's trivial to hflip rasters or scale them by a fixed number of pixels. Quite nice for art packages. Very fast magnify mode.

Unlike the Amiga it has access to the whole 24 bit range. On an STE this could be 4 meg of (chip )RAM , chip registers and ROM. On a Falcon that's 14 meg of chip RAM. Blits can be much bigger than on the Amiga. X/Y count max out at 65536. There is a barrel shifter. Shifting is completely free.

It runs 1 to 3 bus cycles (4 cycles) depending on whether the operation is R/M/W. Ie an and will take 12 cycles, a copy 8 and a clear 4. This is less efficient than the Amiga but the ST blitter always has 160,000 cycles available to it per VBL in hog/nasty mode. This means it's faster by far at clearing/filling memory than the Amiga (even with DMA switched off on the Amiga) and due to bitplane contention not much slower at copying. Masking is obviously slower.

There is an optimisation where the last line of the src need not be read which can speed some blits up. If if the src data is aligned to a 16 pixel boundery.

Combined with the end masks you can do a bit aligned copy where it costs 12 cycles for the start /end (depending on which bits you want to preserve) and 8 for the middle word masks. The Amiga has to use the C channel for this if you want to protect bits in the destination. 6 cycles on the Amiga not including contention if my memory serves. See the HRM for details in case my memory is fuzzy.

I think for a truly generic pixel bitblit (dest = src with bits on the first/last word needing to be preserved) they're probably on par with each other. Assuming bits on the dest need to be preserved.

The ST one is pretty much a straight implementation of raster op with some extensions.

The amiga is quite a bit faster at masking but not 3x faster. More like 1.5 on a five/six bitplane screen due to contention. It takes 24 cycles to mask on the ST.

It doesn't have the nice collision detection feature the Amiga one has. On the plus side sceners worked out how to gourad shade with it on the Falcon

Like the Amiga it will flat out kill the 68k at bit aligned operations. It's fast enough to throw around a 5 plane screen at (320*200) in a VBL. IE 40,000 bytes per frame with an arbitrary shift. Try that on an 8 mhz 68k

It does what it does very well. Much better than the 68k.

Last edited by frank_b; 31 July 2009 at 20:56.
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Old 31 July 2009, 01:14   #236
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Filled/wireframe 3D games should always run faster on Amiga over ST and yes that includes Elite 2!

How does the STE Blitter compare to this as I know it was a lot newer than the Amiga 1985 Blitter?
The STE wasn't the first machine on the ST to have a blitter. I believe the mega ST had one in 1987 so it's not that new. There are sockets on most STs for adding a blitter. I have an STFM and an STF with a blitter fitted.
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Old 31 July 2009, 02:18   #237
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I've never played on an Atari ST.
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Old 31 July 2009, 04:51   #238
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neither did I, however this is exceptionally reminiscent of schoolyard fights when I was but a tiny lass - and yes I mean fights. Be it Moncton, New Brunswick or Lee, New Hampshire... kids could get violent back in the 16-bit wars.

SNES ruled my neighboorhood in the States, there'd be statistics fights and I remember crying once because everyone was mean to the poor Genesis' 64-color pallette. Yeah, I got teased over on-screen colors. I can't stress how serious I am

AND We had CD first! Sure... it had mostly crap FMV games but it had Dark Wizard, Snatcher and the Lunar games.

32X was... a mostrous pile of crap, but it did give us Knuckles Chaotix - which was amazing.

...


OK sorry - derailment, I guess what I'm saying is I feel like I'm back in those days - only now I'm with the Big Kids picking on the poor ST fans that love their system just as much.

I'm an Amiga gal, but I feel for you ST fans. I was there once. *Hugs her CDX*

And fuck the Super Nintendo. :P
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Old 31 July 2009, 06:10   #239
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The SNES was a great system! I still have mine and boot up Super Mario Kart regularly. Much better than that horrible Megadrive/Genesis...
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Old 31 July 2009, 07:40   #240
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In ST Turrican 1 or 2 only title music is sampled, rest is generated and not so good, I felt cheated...
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