Effects in demos that you don't know how they work

category: code [glöplog]

Many times in the past (mainly before 96) I would see some demo effects and would have no idea how they made it technically.

Nowdays it is a bit easier I guess, but there are still some astonishing effects, other subtle other not so much, that raise the eternal demoquestion : How did they do THAT ? (for example, the morphing between so dissimilar objects in 'feed your machine').

Whats yours ?
added on the 2006-01-23 18:11:30 by Navis Navis
Robotnik's polygon voxels.
added on the 2006-01-23 18:13:08 by Gargaj Gargaj
all the bling in the shitfaced clowns newton gba demo
added on the 2006-01-23 18:53:55 by skrebbel skrebbel
best effeects are those what you have coded yourself and you have no idea why the fuck do they look like that and are so cool.
added on the 2006-01-23 19:07:45 by nosfe nosfe
I still haven't figured out how the clouds from Fairlight's Death and Taxes work.
added on the 2006-01-23 19:55:58 by noouch noouch
I still can't get how Jarno managed to fit in this small exe all those pictures of the TaTu girls blowing hyppos and giraffes.
added on the 2006-01-23 20:03:57 by dixan dixan
added on the 2006-01-23 20:06:01 by uns3en_ uns3en_
how they got fortknight to compile
added on the 2006-01-23 22:03:45 by Hatikvah Hatikvah
how is the sword being raytraced on the sphere in Second Reality? :)
added on the 2006-01-23 22:09:18 by pohar pohar
well since camera is static it could be simple double textured sheres
added on the 2006-01-23 22:19:22 by apricot apricot
I think it's a tunnel effect. A precalculated table of texture coordinates that's just scrolled.
added on the 2006-01-23 22:32:44 by Preacher Preacher
the morphing between so dissimilar objects in 'feed your machine'

looked like morphing between precalculated iso values for the objects and using marching cubes to generate geometry.
added on the 2006-01-23 22:33:24 by blackpawn blackpawn
oh yes I see .. good point..... The marching cubes must have had quite a resolution though...
added on the 2006-01-23 22:34:45 by Navis Navis
Well, the effects IS pretty slow.. anyone ever done a marching cubes on an adaptive grid (subdivide the grid where the function changes rapidly)?
added on the 2006-01-23 22:42:19 by Preacher Preacher
Well, the effect IS pretty slow.. anyone ever done a marching cubes on an adaptive grid (subdivide the grid where the function changes rapidly)?
added on the 2006-01-23 22:42:39 by Preacher Preacher
anyone ever done a marching cubes on an adaptive grid (subdivide the grid where the function changes rapidly)?

Quite alot of lads have.
added on the 2006-01-23 23:14:39 by Hatikvah Hatikvah
So why do metaballs always look like sucky metaballs, then? Where are the cool metaplasmas, metaparticles, metadifferential equations, metalandscapes?
added on the 2006-01-23 23:22:33 by Preacher Preacher
why balls dont look like plasmas?
added on the 2006-01-23 23:29:46 by the_Ye-Ti the_Ye-Ti
I have done 'metaparticles' if such thing exists..

Basically, what is happening is that the 1/sqrt per 'particle' calculation is too much work for the cpu, if you want to have a large number of particles. My idea was to render '3d blobs' to a x*y texture z times using 3d textures in opengl hence taking the balance off the cpu. I do the marching cubes later on the cpu.

The result is very interesting, but I wouldn't use it in a demo, 1 metaball or 100, I just don't find it too interesting.

However I am writting a different version of that which looks promising, and will find its way in a demo in the near future...

added on the 2006-01-23 23:42:56 by Navis Navis
Preacher: There have been quite alot of what effects you ask about. Maybe you should look around in some of the non-dezin prods.
added on the 2006-01-23 23:44:59 by Hatikvah Hatikvah
I rather wondered a few times how UncleX and Curly manage to come up with cool concepts for almost every single release ;)
added on the 2006-01-24 00:18:49 by keops keops
stefan, I've watched just about all PC prods from all major parties since the mid nineties. Maybe the effects just don't look as cool as I thought they would.. or maybe they just haven't been done properly. Care to give some pointers?

(contrary to what you might think, I do value "effect" prods.. and some day I might even make some, though with non-DXM colors)
added on the 2006-01-24 00:32:32 by Preacher Preacher
keops: they do it by being atomic supermen.
added on the 2006-01-24 00:33:01 by kusma kusma
I guess how the "meta-worm" (?) part exactly works in Zoom3. It should be some sort of 3d antialiased bob -> volume rendered (similar but much more sharp one in flt's re-recycle)

In the very very beginnings I was rather fascinated by all the nice fx (scrollers, tunnels, bumps, fire, feedbacks, water, wobblers...) such as those in poohwer or in Pie (some of the first scene related stuff I ever saw).
added on the 2006-01-24 02:07:43 by bdk bdk
preacher uhm tried 'Enlight the Surreal' or the clone series?
added on the 2006-01-24 11:03:45 by the_Ye-Ti the_Ye-Ti