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Old 20 February 2015, 18:42   #141
kovacm
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regarding using blitter to faster fill 3D, one color, polygons in games - does anybody have experience with this? There was lot of talks about this but I am not sure if anybody do this in game?

How much blitter would improve 3D games frame per seconds over CPU only version?
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Old 20 February 2015, 20:00   #142
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The Falcon 030 review from ex-Atari owner: http://www.amigareport.com/ar119/p1-9.html
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Old 20 February 2015, 22:46   #143
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The Falcon 030 review from ex-Atari owner: http://www.amigareport.com/ar119/p1-9.html
So a 4M machine cost $1400 or something and was released Jan 1993 (and later in USA), and a funny quote: "But since we all know there will be DSP-based Amigas in the next six to eight months, we can relax." hehehe

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Originally Posted by kovacm View Post
regarding using blitter to faster fill 3D, one color, polygons in games - does anybody have experience with this? There was lot of talks about this but I am not sure if anybody do this in game?

How much blitter would improve 3D games frame per seconds over CPU only version?
We're back to 500 vs ST, oh well I'll try to steer it back

Mostly not done in games, since ST influenced game development on Amiga. Gameplay often required scenes of 40-80 polygons, so to get decent framerates on ST, they shrunk the screen buffer to "very small" to make the polygons smaller; at tiny polygon sizes, the CPU can beat unsophisticated Blitter routines.

(Unfortunately, most 3D games using the CPU were therefore made without regard to faster CPUs, and this affected the Amiga. Because they plot to the screen memory directly, there is much less gain than otherwise possible on a faster CPU with fastmem.)

Therefore, using the Blitter for what it was designed for in 3D games remained largely unexplored. In demos it was, but high polycount fast fullscreen 3D remained elusive since the inclination was always towards simplifying the scene to make a slick production.

On A1200 the Blitter was not upgraded, so on A1200 it doesn't pay off to write a sophisticated 3D routine using the Blitter, except in special cases.
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Old 20 February 2015, 23:12   #144
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Except maybe Thomas Landspurg work especially Virtual World.
Explanation of it's techno here : http://landspurg.net/tomsoft/Demos/V...lds/index.html

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Old 21 February 2015, 00:00   #145
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I love his demos (just linked Trip to Mars in the oldschool group on Facebook an hour ago as it happens ). But that doesn't mean his (or others') demos deliver the performance expected from exploring the Blitter fillrate. Here, he uses the Blitter because he basically has to (because of adding low-poly objects on top of Richter's backgrounds; re-using the palette). A CPU routine would be something like 3-4x slower than the Blitter on top of a picture that you have to restore.

This is why I wrote about reduced slick scenes in my previous post, in demos the tendency was to not solve the problem of fast complex Blitter 3D but to put together an enjoyable presentation instead. Vector Preview by Tai-Pan was a better attempt at a Blitter 3D engine, but it doesn't have scenes comparable to contemporary 3D games.
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Old 22 February 2015, 13:24   #146
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Jack (TTL, later Atari Corp.) never had any plans to base computer on Lorraine!
TTL is sourced as one of money donators for Amiga.
Side to this i've wrote - Atari (buying Atari assets, TTL bough Atari Amiga contract) was able to use Lorraine, later this was confirmed in lawsuit (Atari claim that chips (3) are ready and designed for Atari).

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Commodore first sue Jack because lot of employees left Commodore to follow Jack in new TTL, later Atari Corp with goal to produce RBT computer.
When Jack son, Leonard, first find check on 500K$ only then they discovered contract regarding ex-Atari owners and Amiga team. They use it to contra-sue Commodore and to freez further Amiga development in same way as Commodore prevent Shiraz Shivji and other to work on ST for few months.
For me it is clear - Atari (and Tramiels) at this stage are aware of Amiga existence and they have knowledge abot Amiga (Lorraine) capabilities, they need to create own design in short time to be first o market (RBP)

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entire story can be read in: Atari Inc. Business Is Fun http://books.google.rs/books?id=3FwG...0atari&f=false

I provide source that claims what I wrote that Jack had no plan to make computer based on Lorraine; now could you tell us who is source of story that Jack had plans to use Lorraine?
Well - this is problem, link have no end (only few pages available) - only part of story, side to this it shows point of view from one side - i would be not surprised if they not say everything as Commodore/Amiga people saying slightly different version.

If you are right then it is even more surprising why ST is so limited - why so inflexible display circuit was used ?!? (idea that ST was designed in rush, in situation where enemy competitor acquired superior technology can explain this rush - if this is not the case then sorry but i have no explanation).
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Old 22 February 2015, 14:19   #147
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If you are right then it is even more surprising why ST is so limited - why so inflexible display circuit was used ?!? (idea that ST was designed in rush, in situation where enemy competitor acquired superior technology can explain this rush - if this is not the case then sorry but i have no explanation).
Computers For The Masses Not The Classes -> [ Show youtube player ]

Low End Computers -> [ Show youtube player ]
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Old 22 February 2015, 15:51   #148
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Computers For The Masses Not The Classes -> [ Show youtube player ]

Low End Computers -> [ Show youtube player ]

Well - this is not explanation of anything - i can understand 9 bit CLUT (lower pin count on IC, Amiga is 12 pins but still there is nothing difficult to add 5'th bit and as such to have 15 bits but this mean 3 additional pins on IC and no longer 48 Pin DIL sufficient etc).
However lack of hardware pointer (single sprite) for mouse cursor in GUI is hard to explain - blitter can be explain as bigger problem - need to be synchronized, working concurrently with CPU and VDC etc
Mentioned HW scroll, lack of overscan... Once again - ST have graphics comparable to CGA + HGC - nothing fancy i would say.
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Old 22 February 2015, 20:20   #149
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^ please stop conversation about amiga/atari.

I will open new thread shortly! since I also want to hear more opinion about it.
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Old 22 February 2015, 22:35   #150
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Originally Posted by pandy71 View Post
Well - this is not explanation of anything - i can understand 9 bit CLUT (lower pin count on IC, Amiga is 12 pins but still there is nothing difficult to add 5'th bit and as such to have 15 bits but this mean 3 additional pins on IC and no longer 48 Pin DIL sufficient etc).
However lack of hardware pointer (single sprite) for mouse cursor in GUI is hard to explain - blitter can be explain as bigger problem - need to be synchronized, working concurrently with CPU and VDC etc
Mentioned HW scroll, lack of overscan... Once again - ST have graphics comparable to CGA + HGC - nothing fancy i would say.
It's obvious that you have no experience with the CGA standard... The Atari ST is superior.
But the lack of hardware scrolling is very strange...

Edit:
Atari ST modes: 320x200 16 colors, 640x200 4 colors, 640x400 2 colors (requires special monitor), palette of 512 (3-3-3 R-G-B)
CGA modes: 160x200 16 colors*, 320x200 4 colors, 640x200 2 colors, palette of 16** (1-1-1-1 R-G-B-I)

(* actually an undocumented text mode, no commonly used)
(** actually this is even less impressive as the colors aren't freely selectable - hence the characteristic "CGA look")

Last edited by Megol; 22 February 2015 at 22:54.
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Old 22 February 2015, 22:42   #151
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It would be fun to see ST fans try to show off ST games that would impress Amiga fans, but all they do is try to get equal to Amiga. That's an important point. If they really were equal, there would be a bunch of games that had the upper hand in performance. If they can't find some, maybe it's time to stop insisting?
Yeah i feel the same way when Amiga fans try to make the Amiga play Doom and Quake
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Old 22 February 2015, 23:41   #152
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Mostly not done in games, since ST influenced game development on Amiga.
I undestand this but does anybody know how much faster 3D games would be if blitter was used for polygon fill?

does anybody have any numbers?

e.g. Elite II was written on Amiga. David B. could use Amiga blitter for filling polygons and CPU on ST. But he did not. Why? He does not have time or there was no speed gain?

so: does anybody have numbers?
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Old 22 February 2015, 23:55   #153
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Originally Posted by kovacm View Post
e.g. Elite II was written on Amiga. David B. could use Amiga blitter for filling polygons and CPU on ST. But he did not. Why? He does not have time or there was no speed gain?
Or simply: Does it pay off to improve the performance on the Amiga or would people still buy the game without the extra effort put in?
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Old 23 February 2015, 00:27   #154
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TTL is sourced as one of money donators for Amiga.
Side to this i've wrote - Atari (buying Atari assets, TTL bough Atari Amiga contract) ...
replay is here http://eab.abime.net/showthread.php?p=1005783 in new thread "Jack Tramiel and Lorraine"

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Or simply: Does it pay off to improve the performance on the Amiga or would people still buy the game without the extra effort put in?
one of many possible reason, I agree.

but still, does anybody have any numbers how much faster 3D fill would be with blitter (or slower)?

Last edited by TCD; 23 February 2015 at 00:33. Reason: Back-to-back posts merged.
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Old 23 February 2015, 00:35   #155
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Can we lay off the off-topic stuff on this forum please? If you want to discuss the Falcon vs A1200 performance here that's fine, but please leave all speculative discussions that lead nowhere 30 years later out of it.
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Old 23 February 2015, 09:38   #156
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Can we lay off the off-topic stuff on this forum please? If you want to discuss the Falcon vs A1200 performance here that's fine, but please leave all speculative discussions that lead nowhere 30 years later out of it.
it is unanswered question and I am not one who made "speculative discussions".
On contrari: I always hear argument "it is Atari port so it does not use blitter" (we could read same argument here in this thread). I would like if someone could support this argument with facts.

But you are right, I will open another thread with this topic. Stay tuned...
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Old 23 February 2015, 09:46   #157
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Sorry, I should have quoted you and stated that I meant the 'Jack Tramiel and Lorraine' part. Feel free to make another thread about the blitter comparison
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Old 23 February 2015, 10:13   #158
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Sorry, I should have quoted you and stated that I meant the 'Jack Tramiel and Lorraine' part. Feel free to make another thread about the blitter comparison
ah, ok

here is new thread about "Using blitter for filling 3D polygons": http://eab.abime.net/showthread.php?t=77162
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Old 23 February 2015, 12:00   #159
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Quote:
Originally Posted by kovacm View Post
I undestand this but does anybody know how much faster 3D games would be if blitter was used for polygon fill?

does anybody have any numbers?

e.g. Elite II was written on Amiga. David B. could use Amiga blitter for filling polygons and CPU on ST. But he did not. Why? He does not have time or there was no speed gain?

so: does anybody have numbers?
Saying that Elite II was written on Amiga is plain wrong. David Braben was an ST fanboy, a lover of this machine, and as such made the game for ST, then ported accross to the amiga. That's why Frontier Elite II use mainly the CPU, it's shared code.

You don't know your classics heh ?
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Old 23 February 2015, 14:02   #160
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Saying that Elite II was written on Amiga is plain wrong.
"Braben originally programmed the game for the Amiga in 68000 assembly language. It had roughly 250,000 lines of code, which were ported from 68000 assembler to the PC's 80286 assembler by Chris Sawyer."

https://en.wikipedia.org/wiki/Fronti...nt_and_release


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That's why Frontier Elite II use mainly the CPU, it's shared code.
ok. what game than does use blitter instead of CPU for 3D?

btw more sensible explanation than "it is ST game port so there is no blitter use" is that blitter is not used since Elite II appear in time when there were more powerfull machines than plain ST or A500 where blitter is slower than main CPU.

and where did you find that "David Braben was an ST fanboy"? As I read, he was more BBS/Archimedes fan since best, most complete, version of Elite 1 is for Archimedes. Zarch is also writen first Archimedes...

Last edited by kovacm; 23 February 2015 at 14:08.
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