pouët.net

I've seen this very oldskool effect many times...anyone can tell me what this is or how its done?

( at 01:27 )

http://www.youtube.com/watch?v=pV7URFzNSno&feature=related

It's a table-effect.

This frankly looks like a few frames of animation rendered out in some commercially available raytracer which can do volumetric lighting, otherwise they would have probably made the effect a little bit longer to enjoy.

ARGH scrap what i said, i was looking 10 seconds too early in the video. What kusma said.

Oldschool?!! This is oldschool:

texture mapping

Oldschool?!! This is oldskool:

wow! that kid in the middle in front....he looks like he's the smartest..if not he prolly be on crack!

anyways...since you ppl are watching this thread..any words on how its done?

A lookup per pixel in a 2d table pointing into a texture and then scroll the texture pointer (and maybe (like in the link) the table too)

Divide the screen into n*m quads, calculate u,v for each vertex using some fancy formula and texturefill the whole thing.

Ah, psycholns's solution is probably the right one for in this case :) Sorry for misinformation.

yeah, there are even versions of that effect with 2 or more tables added. This effect seems to use a per-screen-pixel table, and scroll both the texture AND the screen. For the precomputed equation used to deform, must be something like a sphere equation. And yeah, interpolation with mapped quads are better for these effects. (less memory took for lookup tables, hability to compute the equation in real time.)

Which is better depends on the hardware, formula used (there's a lot of things you can't do in a 16x16 interpolation) and how dynamic you want it to be.

funny thing about it is that it's such an amiga-only effect - i only saw like 2-3 pc demos using it... not that it was harder or anything, just... not used i guess

Looks like a variation of bitmap tunnels (tutorial here http://sol.gfxile.net/gp/ch17.html ..) and there used to be craploads of pc demos with such effects.. doomsday did several variations, for example.

thnx brothers, my ego is more than satisfied

Gargaj, perhaps if you count it as somehow distinct from wormholes, tunnels (with bazillion different distorts), bumpmaps, lenses, planes etc..

yes, that's what i meant - this certain LUT effect was used a lot more on Amiga as far as I saw... no idea why.

it's well featured in older hellcore (mrock) demos/intros.

Gargaj: ephidrena used variants of that "ball" in 10 demos or so, simply because it was the only formula Loady managed to implement in those 3 years...

maybe texture-shift in a torus looked sexy on amiga but is way too easy on pc with GHz instead of MHz...i guess thats why!

saw that demo the first time and it surely rocks!

how do those differ to "tunnels without depth"?

Jizz or Stash from TBL featured such an effect if i remember right...