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Amiga computer related discussion => Amiga Software Issues and Discussion => Topic started by: Skyraker on July 18, 2008, 12:07:53 AM
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Spaceballs manage to get either SOTA or 9 Fingers on to a floppy...?
Yes i'm getting back into Emu, but really how?
Especially 9 fingers... ok it's lo res and probably 4 bit colour.. but still, 880k? I'm boggling at how it was done... it's video of a sort..
Must be some ex demo coders still about that can explain it to me....
I tried explaining to the missus how bloody small a floppy disk really is, but in the age of USB sticks it's just falling on deaf ears.
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Compression?
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Compression fair do's, but we're still talking 880K...
Maybe i'm half cut, but i'm still not having it.
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The drawings are a single polygon plotted on a single bitplane. The rest of the eye candy is drawn independently on the other 4 bitplanes. Amiga supports polygon acceleration but it isn't texture mapped or fast at more than 1 bitplane.
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9 Fingers looks like it's using 2 bitplanes for the polygons, and it isn't just one.... It's so realistic there must have been video converted, there's no way it's drawn from scratch.
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It was hand-traced from live video.
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It was hand-traced from live video.
SOTA I'd agree, but 9 fingers?
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I thought they were streamed vectors rather than animated bitmaps. They would compress and stream to almost nothing?
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It's just vectors, indeed (basically coordinates for the polygons to fill).
Draw the polygon using the blitter linedraw fill mode, and fill with blitter.
Hardly anything magic about it.
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@ Piru
But it still looks awesome
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pyrre wrote:
But it still looks awesome
Only Amiga makes it possible. :-D
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Typical case of a really nice idea !! Two of my favourites demos
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weirdami wrote:
pyrre wrote:
But it still looks awesome
Only Amiga makes it possible. :-D
Hardly...
In actuality anything that can plot on the screen can do it, just no hardware accelerator: done by the CPU.
As for the size issue, as Piru mentions, it's pretty standard stuff. For each polygon with N corners you need 2 coordinates, an X and a Y. That can be stuffed in 2 bytes each (so 4 bytes) or you can do 1 byte each because of the low resolution (<255). You can also do compression on those (so effectively having less than 1 byte per coordinate), like a lzh/hoffman type stuff. Finally you don't need the coordinates for each frame because you can use animation/tweening/interpolation to move a certain corner from location A to location B. That's HUGE savings.
An example of a great game that was really small, yet pretty awesome, and used the same techniques: Out Of This World / Another World.
As correctly stated by SamuraiCrow, you can very easily stuff lots of data that are 1 plane because each pixel is represented by 1 bit, which means that an entire bit plane of 320x240 pixels is 320*240/8 bytes. Pretty small. Furthermore, you'd typically use Run Length Encoding (RLE) which is very simple but gives huge savings. A simple version goes like this: if you have a 'run' of 20 pixels in the ON state and then 40 pixels in the OFF state (see-through) and then 30 more pixels in the ON state, then you could take 3 bytes to describe it: 20,40,30 and your code would interpret those as 'runs', now, if the next byte was a 0 for example, you could use that as a special 'key' to denote that the next few bytes won't be runs, but individual pixel values, so the next 1 byte could have alternating pixels, which would look like: 10101010, which in decimal would be: 170 and NOT 170 pixels in a row (that would be a 'run' and wouldn't have a leading byte of value 0).
All in all, demos fscking rule! And the Amiga demos are some of the sweetest!
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da9000 wrote:
weirdami wrote:
pyrre wrote:
But it still looks awesome
Only Amiga makes it possible. :-D
Hardly...
:roll:
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SOTA is a great demo that is rightly popular, but if you're going to pick a demo to marvel over the code, don't pick that one.
Theres nothing in SOTA that is very hard to do. The vectors for SOTA were hand traced, and that would have been laborious and annoying, but not difficult. Also, I have it on good authority (StingRay :-)), that the code itself is pretty awful (don't forget that the original SpaceBalls release had to be fixed by Skid Row for it to work on most Amigas; and that was even before AGA came out).
I'm guessing for 9-fingers they had automated the process of vectorising video frames.
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The 9fingers source video is on YouTube...
Will search for the link.
/edit
here we are
http://youtube.com/watch?v=WgriMuXZ3QY
and
http://youtube.com/watch?v=MgcfpQqpf5g&feature=related
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Did anyone ever try 3D glasses (Red/Blue?) on that scene in SOTA with the rotating 3D grid? Man it was amazing in 1992, I almost wet myself.
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I´ve never though about that.... I need to get one of those glasses and try :-)
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I hadn't realised that it was 3D either...I bet it must have looked bloody incredibly back in the day!
Speaking of which, I recall reading interviews with participants of the demo competition in which SOTA was released, and the reaction was rather mixed. Some folks loved it, other's criticised it's old fashioned routines.
Personally I love it, and will never forget the day I first watched the demo on my A500 as a child. Truly magic. Those were the days.
Cheers,
James
x
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Especially 9 fingers... ok it's lo res and probably 4 bit colour.. but still, 880k?
It's 2 disks, btw. 880k*2
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Its impressive fitting stuff into small memory. If anyone has an x86 box and hasn't seen The Product - this is damn impressive viewing for 64K!
http://pouet.net/prod.php?which=1221
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how come no one mention the odyssey demo....?
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weirdami wrote:
da9000 wrote:
weirdami wrote:
pyrre wrote:
But it still looks awesome
Only Amiga makes it possible. :-D
Hardly...
:roll:
Trying to bring some semblance of reality into the conversation. I apologize, please go back to fantasy land...
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alexh wrote:
Did anyone ever try 3D glasses (Red/Blue?) on that scene in SOTA with the rotating 3D grid? Man it was amazing in 1992, I almost wet myself.
Actually, I did, red/green and red/blue
Didn't work for me, although I did create a pseudo 3d movie from a vhs source using a framegrabber, and color conversion and a lot of patience :-D
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pyrre wrote:
how come no one mention the odyssey demo....?
It came on 11 floppies IIRC?
And I was hardly impressed by Odyssey demo when I watched it, boring and lacked cool effects.
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It came on 11 floppies IIRC?
No. only five....