3D in demos - F030 vs Amiga 1200

[kovacm]

Originally Posted by StingRay

He sure is. I just don't know why.

lol! My native language is not certainly english but please stop put "words in my mouth". wasting yours and my time.

and: "It is also a known fact that chunky effects..." - I was not sure about this so I ask to be sure that it is a fact.

I do not care about being right or wrong in my opinion (it is opinion after all ) or to impose it to others, I am care about learning new stuff

[Leffmann]

Originally Posted by kovacm

is it right to assume that Fast and Chip ram speed are same from MC68000 point of view (in cycles) with difference that Fast ram is _always_ accessible to MC68000?

Yep, but fake fastmem a.k.a slowmem, the most common memory expansion for A500 that connects in the trapdoor slot, appears as fastmem to the system, but shares the chipmem bus and is subject to the same speed penalties.

[britelite]

Originally Posted by kovacm

Btw Falcon run DHS demo at 100% same speed as plain ST.

Ahem... At least on the video you posted the demo runs smoother than on a real ST.

thanx! GREAT DEMO - better than new ST demos.

I wouldn't call Hardknee Lotus a great demo. And I have improved versions of pretty much every single effect shown in the demo

But truth to be told, texturemapped 3D isn't very interesting on the A500 (or the ST), because at the end of the day it will still be slow and look quite bad.

[kovacm]

Originally Posted by britelite

Ahem... At least on the video you posted the demo runs smoother than on a real ST.

maybe you are right: here is another video - http://dhs.nu/video.php?ID=171
(recorded from emulator...)

Originally Posted by britelite

I wouldn't call Hardknee Lotus a great demo. And I have improved versions of pretty much every single effect shown in the demo

will you share it?

Originally Posted by britelite

But truth to be told, texturemapped 3D isn't very interesting on the A500 (or the ST), because at the end of the day it will still be slow and look quite bad.

I find it interesting to see "modern" effects (including texture mapped 3D) on old hardware - even on C64 and Atari 800!

[britelite]

Originally Posted by kovacm

maybe you are right: here is another video - http://dhs.nu/video.php?ID=171
(recorded from emulator...)

Yeah, that one is closer to the real speed. And don't get me wrong, I think the framerate on most fx is pretty decent, but the Falcon-recorded version of the demo still gave the wrong impression

will you share it?

They will probably appear in future demos of mine

I find it interesting to see "modern" effects (including texture mapped 3D) on old hardware - even on C64 and Atari 800!

It was interesting back in the days, but I do think they've been done to death on the c64 and atari 8bit, and most of them looked like crap. Same goes for the ST, and I've probably rehashed the LUT-effects to death on the A500

[s2325]

On Atari 8-bit most, but not all textured objects are precalculated animations, not real time.

[kovacm]

Originally Posted by s2325

On Atari 8-bit most, but not all textured objects are precalculated animations, not real time.

raycasters are realtime [ Show youtube player ]

and e.g. this [ Show youtube player ] is precalculated??
(quite possible since there is lot of time before demo starts... and what part of calculation is "precalculated" - entire frames are not for sure since there is not enough RAMa...?)


@britelite I am anxious to see how far you improve it I would say that yours 3D scenes are two times more complex than from DHS demo...?

and can you explain me why Fast ram is required? MC68000 in A500 with only chip RAMa have full write/read speed (custom chips do not steal MC68000 cycles) unless you use more than 4 bitplanes? Is there something else that will steal cycles from MC68000 in accessing chip ram?

[s2325]

Most of 3D demos on Atari 8-bit are stored in big files and require 320KB of RAM, that may be a big hint.

[britelite]

Originally Posted by kovacm

and can you explain me why Fast ram is required?

For Hardknee Lotus it was mainly because I didn't want to design a demo around a diskloader, but rather have everything in memory from the start. All the individual parts work fine with 1MB of memory, and if I make another 3D-show on the A500, it will load from disk instead of requiring extra memory.

Originally Posted by s2325

Most of 3D demos on Atari 8-bit are stored in big files and require 320KB of RAM, that may be a big hint.

True, they require 320kB of RAM, but then again, they don't load additional data during the demo. And there's been 3D-stuff on unexpanded Atari 8bits too.

[sokolovic]

Originally Posted by hooverphonique

I'm pretty sure Nexus 7 runs fine on a stock A1200, but it doesn't have much of the 3D stuff requested by the OP...

I guess "guard shaded" should've been "gouraud shaded" ;-)

Nexus 7 runs on a stock A1200. It also runs on CD32 !

[ImmortalA1000]

Originally Posted by kovacm

^^
can I make one observation?

on ST, coders need, as you said "to emulate" (I would prefer phrase "to find way") to achieve Amiga capabilities. One of need was to display more than 16 colors onscreen so Atari coders find a way in 1987.: Spectrum 512 (http://www.asterius.com/atari/spectrum.html)

It is nice to see that Amiga coders adopt this idea. as I said before: I want to see how far coders manage to push limits of hardware boundaries

btw "manually Copper can do more (but not more than 50 few changes per scanline)" - copper will do this with 0% CPU time, and some bus time, right? and one more thing: how much bus time will consume hires with 4 bitplanes on OCS/ECS?

Quantum Paint was first, loads Amiga 320x200 HAM6 images. Uses C64 style palette color alternating to simulate 4096 colours.

AFAIK 640x512 display uses up pretty much all bus bandwidth in pre-AGA machines (not sure about '32 bit' A3000 chipset/bus) which is why writing a fast arcade game in 640x512x16 colours is never going to happen. OS defaults to 640x256x4 colours for a very good reason

[kovacm]

Originally Posted by ImmortalA1000

Quantum Paint was first, loads Amiga 320x200 HAM6 images. Uses C64 style palette color alternating to simulate 4096 colours.

Quantum Paint was introduced in 1988. after Spectrum512
http://www.stickhead.pwp.blueyonder....ntumpaint.html

[ImmortalA1000]

Originally Posted by kovacm

Quantum Paint was introduced in 1988. after Spectrum512
http://www.stickhead.pwp.blueyonder....ntumpaint.html

Ahh I should have said first program to display HAM6 images from Amiga 500/1000/2000 not first to display more than 16 colours on screen in lo-res mode It's the 4096 colours business like C64 MCI/FLI etc trick modes to boost palette range I was concentrating more on not just the palette swapping per scanline aspect.

[alexh]

Maybe its because you got your facts wrong?

[Mrs Beanbag]

Originally Posted by Flash951

HELP! HELP! I'm alone in the battle with the infidels over at the parallel thread in the Atari ST camp.

http://atari-forum.com/viewtopic.php...5174&start=100

um just one question, how do you think an Amiga that has no Fast RAM actually works? (such as any stock A500, A600, A1200)

[Flash951]

On A500 there is no big problem. as the chip RAM bus has capacity for both cpu and co-processors. For A1200, you need fast ram of course, it will speed up the CPU fra about 2x-2x A500 to about 5x.

[pandy71]

Originally Posted by Flash951

HELP! HELP! I'm alone in the battle with the infidels over at the parallel thread in the Atari ST camp.

http://atari-forum.com/viewtopic.php...5174&start=100

But why? This is plain waste of time - from time to time, some frustrate enters forum and create this kind of topic - to compare something you need to understand all implications - usually such threads are not for comparison but to prove that some machine is better.
Well plainly Amiga is superior machine to Atari especially when ST is compared to Amiga(500), Falcon is different story as DSP on board that may be used to perform GPU offload. There is no comparable Amiga to Falcon.

[Flash951]

For me, Atari ST and GEM is more comparable to the 8 bit system C128 and GEOS, rather than the Amiga. GEOS looks better though.

[Flash951]

Originally Posted by ImmortalA1000

Ahh I should have said first program to display HAM6 images from Amiga 500/1000/2000 not first to display more than 16 colours on screen in lo-res mode It's the 4096 colours business like C64 MCI/FLI etc trick modes to boost palette range I was concentrating more on not just the palette swapping per scanline aspect.

No, the C64 MCI/FLI uses two different colors on the same pixel in interlaced screenmode to make a new "third" color. In practice this will give maybe 30 more colors in addition to the sixteen built in, because you have to use low contrast once to not have flickering. In theory, maybe 128 colors.

The HAM6 - 320×200 to 360×576 (ocs, ecs) and the HAM8 (aga - (1440x576, 256 000/16 mill colors) is proper screen modes (Hold and modify), no tricks, but with some limitations, uses only 6 bit per pixel.

The Amiga Juggler demo from 1986 displays 30 f/sec fullscreen in HAM6 on a stock 68k Amiga.

[Photon]

The Juggler is not a demo, but an animation. And you don't know it runs 30 fps.

Just calm down and say that Amiga is better than Atari ST. It's perfectly true, so let *them* make fools of themselves trying to prove whose computer is best, instead of trying to convince ST-lovers. They'll just drag you down to their hardware level and beat you with their MIDI interface.