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Amiga Marketplace / Re: 5 Amiga books for sale U.S
« Last post by Pyromania on March 28, 2024, 10:18:03 AM »
Sent!
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Hi there!

Folks in Montréal are organising a Summer School on retro-development, with a special focus on the Amiga!  8)

"A summer school dedicated to retro gaming, which invites both humanities and engineering to provide unique insights on retro gaming, both theoretical and practical, and opportunities for cross-fertilization among research fields. Supported by the ACM SIGSOFT."  :D

Check it out!
Tygre
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It was ages that I intended to dig up some 20+ years old code and use it to play with PED81C a little more. Finally I got around to do it and came up with a new test program called Zoomaniac.
Details in the video and in the manual excerpt below. Download available at https://retream.itch.io/ped81c.

https://www.youtube.com/watch?v=eehqapb20fE

Code: [Select]
--------------------------------------------------------------------------------
OVERVIEW

Zoomaniac has been written to evaluate the performance on a stock Amiga 1200 of
a general-purpose texture scaling routine that writes directly to a PED81C
raster.


--------------------------------------------------------------------------------
PERFORMANCE

The following results are relative to the full screen effect that zooms the
cosmonaut in and out.

On a stock Amiga 1200, the execution speed is between 25 and 26 fps. If the
staggered lines are turned on, the performance drops by about 1 fps (which was
unexpected, since all that such option adds is a Copper WAIT and a Copper MOVE
for each rasterline).
Given that the DMA load caused by PED81C is "double" (see its documentation for
the details), a version that uses only half the number (2) of bitplanes has been
made to check the performance as if the Amiga had a native chunky video mode.
Surprisingly, the performance did not improve at all: relatively to the CHIP bus
access, the scaling code must interleave so nicely with the bitplane data
fetches that having more bus cycles available does not make any/much difference.

An Amiga 1200 equipped with a 68030 clocked at 50 MHz and 60 ns FAST RAM easily
performs at steady 50 fps. To find out the maximum performance, new tests were
made with special versions of the program that had the video synchronization
code disabled.
The speed when running the program normally was between 77 and 78 fps. The
staggered lines option lowered the fps by about 2. The 2 bitplanes versions
performed better, reaching 80-81 fps or, with the staggered lines on, 79-80 fps.
Like on the stock Amiga 1200, the extended Copperlist that implements the
staggered lines causes a small and similar performance drop. Instead, the
halving of the bitplanes DMA load did produce a speed increase.

The following table sums up the results.

S = stock Amiga 1200
E = Amiga 1200 68030 @50 MHz / 60 ns FAST RAM (Blizzard 1230 IV)
2 = 2 bitplanes on
4 = 4 bitplanes on
L = staggered lines on

  |     4 |     L4 |     2 |    L2
--+-------+--------+-------+-------
S | 25-65 |  24-25 | 25-26 | 24-25
E | 77-78 |  75-76 | 80-81 | 79-80

Notes:
 * when FAST RAM is detected, an alternative and more suitable scaling routine
   is used (although writes still happen to CHIP RAM);
 * on (some?) machines equipped with FAST RAM an even faster strategy would be
   rendering to FAST RAM and then simply copying at the maximum speed the
   rendered frame to the CHIP RAM raster.


--------------------------------------------------------------------------------
TECHNICAL NOTES

* The scaling routine fits any rectangle from a texture into a rectangle of any
  size and ratio of another texture with nearest-neighbor matching.
* Logic and rendering are totally asynchronous: the logic runs always at 50 Hz
  and the rendering never stops (unless it reaches the limit of 50 fps, imposed
  by the display refresh rate), thus exploiting the machine's full potential.
* The screen buffering employs three buffers in CHIP RAM.
* The screen resolution is 1020x256 SHRES pixels, which correspond to 255x256
  LORES-sized physical dots and to 128x256 logical dots.
* The code is 100% assembly.
* The program takes over the system entirely and returns to AmigaOS cleanly.

CHANGELOG

March 27, 2024
* Added the Zoomaniac demo.
* [PED81C Voxel Engine] Made a couple of minor changes.
* [PED81C Voxel Engine] Updated documentation.

January 1, 2024
* Rebuilt demos against latest custom framework.
* [PED81C Voxel Engine] Optimized slightly background rendering.
* [PED81C Voxel Engine] Corrected benchmark fps calculation (312 rasterlines were considered instead of 313).
* [PED81C Voxel Engine] Built against latest custom framework.
* [PED81C Voxel Engine] Updated, extended and fixed documentation.
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Miscellaneous / Re: AMIGA.org Server Outage
« Last post by BozzerBigD on March 27, 2024, 04:50:48 PM »
@F0LLETT

Take a compliment when it's offered. As an aside, I am happy with THEA500 Mini but again I think it's only right to wish you every success with your A600GS launch. Much love!
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Another World Beast & Slug Budget Cutscene - Original VS Fan Made Version

How iconic was the beast chase scene in Another World!? Plus, the infamous alien slugs? Well, to honour Another World, I have recreated the opening level on a budget! Imagine sock puppet slugs, terrible acting and Lego stop motion animation. Yup, its as bad as you can imagine!

https://www.youtube.com/watch?v=WNR6bKU1ER0
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General chat about Amiga topics / Re: Next Gen Amiga with Power10?
« Last post by Boing-ball on March 27, 2024, 02:37:45 PM »
Oh boy, that’s like saying latest Intel processors are made for Windows 2.0.

By A400, I presume you mean AS/400, which was renamed to OS/400 way back in 1988, only to be renamed a few more times since, currently it’s known as simply… i. Also, not UNIX (though providing compatibility layer for AIX software, AIX being the IBM UNiX)

Calm down Sheldon 🤣🤣🤣🤣 This ain’t a nerd off… 🙄

The OP was only asking about Power10. ideally if he/her googled, then they would have found the answer.

 It’s been a while since using Advance Interactive eXecutable. When I worked with those systems they were known as SystemP and SystemI. Besides you can run LINUX on Power Systems as well 😉 It was an option when setting up LPARs on the HMC when I was administrating them.
Fun fact, both AIX 4.3.3 and then later AIX5L had LINUX extensions 😉 AIX was based off SystemV UNIX and also incorporated BSD. Still around even though HP/UX and SUN Solaris are hardly around in the present.

Haven’t a clue these days what IBM are doing, apart that they bought up RedHat and pushing Cloud.

I’m just interested in the retro systems and glad I’m out of that rat race and putting up with people who have no people skills 😬
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Miscellaneous / Re: AMIGA.org Server Outage
« Last post by F0LLETT on March 27, 2024, 09:06:29 AM »
Well, this is sysadm 101 stuff - plan for disaster - don’t put services and backups (eggs) all in the same physical location (basket). And it’s never been easier to make services georedundant, just about all providers offer multiple geographically separated sites and tons of tooling to help implementing proper redundancy. It’s easily worth the effort.

Well I have a working backup server of amiga.org, so we are good there, :).

@F0LLETT

Thanks! That didn't take that long! Any more Amiga forum outages and I think Discord and Facebook will take over permanently! Just a worry I have!

Thanks for all the work you do and glad you have all your infrastructure intact to launch the A600GS. Good luck!

We did'nt take a week, the server provider did. They had a serious issue. Its now resolved.
Full info on outage is on amigaworld.
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Miscellaneous / Re: AMIGA.org Server Outage
« Last post by BozzerBigD on March 27, 2024, 08:20:16 AM »
@F0LLETT

Thanks! That didn't take that long! Any more Amiga forum outages and I think Discord and Facebook will take over permanently! Just a worry I have!

Thanks for all the work you do and glad you have all your infrastructure intact to launch the A600GS. Good luck!
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General chat about Amiga topics / Re: Next Gen Amiga with Power10?
« Last post by kolla on March 27, 2024, 05:40:43 AM »
Quote
IBM propriety CPU for AiX and A400 UNIX servers

Oh boy, that’s like saying latest Intel processors are made for Windows 2.0.

By A400, I presume you mean AS/400, which was renamed to OS/400 way back in 1988, only to be renamed a few more times since, currently it’s known as simply… i. Also, not UNIX (though providing compatibility layer for AIX software, AIX being the IBM UNiX)
10
Miscellaneous / Re: AMIGA.org Server Outage
« Last post by kolla on March 27, 2024, 05:20:01 AM »
Well, this is sysadm 101 stuff - plan for disaster - don’t put services and backups (eggs) all in the same physical location (basket). And it’s never been easier to make services georedundant, just about all providers offer multiple geographically separated sites and tons of tooling to help implementing proper redundancy. It’s easily worth the effort.
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