demoscene

Metablob Multitouch (Metablob original code by Adrian Boeing) (Composition by gtoledo3)

Author: gtoledo3
License: Creative Commons Attribution-NonCommercial-NoDerivs
Date: 2011.10.04
Compatibility: 10.5, 10.6, 10.7
Categories:
Required plugins:
kineme multitouch

This is based on metablob by Adrian Boeing, which is a classic metablob type shader with some animated metablobs. I've added some functions, chopped out the animation, added more metaballs and set it up for multitouch.

Demo time again.

psonice's picture

Yep, been a while since I did one of these demoscene posts, but revision (the breakpoint/main easter party replacement) and the gathering parties have passed, and there's plenty of new + interesting stuff released. Downloads (mostly PC/windows) available from the pouet links.

Here's a small selection:

numb res by Carillon & Cyberiad & Fairlight

Yep, new fairlight demo, with smash's crazy coding skills in full effect here. Doing fluids at this quality, in realtime, is insane. The demo is great too. And it's rendered in 3D. I'll put the anaglyph version up as most of you guys will have the shades, if not watch the 2d version here: http://www.youtube.com/watch?v=wPdYfn9_dIM http://www.pouet.net/prod.php?which=56900

We Crave Sustenance by PlayPsyCo

I liked the tune + style of this one. Nothing all that incredible compared to the fairlight demo (this one won at the gathering, fairlight came 2nd!) but still cool. http://www.pouet.net/prod.php?which=56901

Shake Off The Dust by Elude

Low res, but some really creative effects and nice design. This was made on an amiga, and it puts a lot of the stuff we do in QC to shame - anyone want to try matching it on equivalent hardware? That would be a 68k mac! :O

http://www.pouet.net/prod.php?which=56884

Monstra Kosa by Satori

Software rendered. Not everyone's cup of tea - satori have a strange, hard but psychadelic eastern european style. And I'm not going to bother linking to youtube, the compression just can't cope with this - watch it realtime on a fast PC if you can, if not download the video from here: http://zd3n.com/files/str_monstra_kosa.mp4 http://www.pouet.net/prod.php?which=56881

Code Is My Pron by Nuance

This one's 4k. The audio is.. different. But the visuals are great. Somewhere in the pouet comments somebody linked the shader too, plenty to learn in there I think (if you can decipher it). From a very quick look, I think it's possibly simple feedback effects, but performed on a 3d texture. The texture is then raymarched. (this is an educated guess, might be wrong :) http://www.pouet.net/prod.php?which=56866

Raytracing + raymarching in QC

psonice's picture

I've started to write my own raymarching renderer in GLSL + QC, thought I'd share my output (and some of the code + comps) here.

This is roughly where I'm up to so far:

Moderately complex geometry, lighting + soft shadows. The shadows were hard, I wanted decent quality soft shadows from a point light without too much of a speed hit.

The camera can be moved + rotated in any direction, the light can be moved freely. Adding additional lights with or without shadows is trivial :) Ambient occlusion (true AO, not screenspace) is also trivial, but it seems to look better without it. Animating the object is also trivial.

No .qtz yet, until I've worked out some of the bugs and optimised it a bit. As it stands, the camera can't move outside of a limited space, and repeating objects glitch badly if they're not tightly managed.

Quick rundown of what raymarching is:

  • You render a single polygon, with a GLSL shader (openCL would also work, but without major benefits and with major compatibility issues ;)

  • Inside the shader, you determine camera position and direction for each pixel, and you do a form of raytracing in that direction (this is the 'raymarching' step).

  • To raymarch, you calculate the distance from the current position to the nearest surface. Then, you can 'march forwards' along the ray by that distance, and repeat, until you hit an object.

  • You then calculate the surface angle at that point where the ray hits, so you can do lighting and the rest.

It's also referred to as 'distance fields' because everything is based on the distance from a surface, or 'sphere tracing' because you effectively calculate the intersection of a sphere and the geometry.

Benefits of this kind of rendering:

  • It's "fast" (well, for raytracing!)

  • The scene can be infinitely big and complex. Trivial example: an infinite 3D grid of cubes. This is very quick and easy with raymarching. How many can you do with an iterator? ;)

  • Advanced lighting effects, reflections, refraction, AO, subsurface scattering are all fairly simple. You can use them all at the same time, with a bit of a performance hit.

The downside:

  • It's hard :( Just moving the camera becomes a brain twister.

  • It's slow, compared to normal rendering. 640x480 at 30fps needs a high end GPU.

  • You can't use 3d models and the like. Everything gets built with mathematical formulas.

More from the demoscene: perhaps the best 4 kilobytes imaginable

psonice's picture

Once again not really demoscene related, but this blew my mind so much I figured you'll all want to see it :)

http://www.pouet.net/screenshots/55758.jpg

It's a 4KB demo by Quite and Orange. Just 4KB total, code and data, including all visuals and sound. I've no idea how the sound was made, but for 4KB it's amazing. I've no idea how the visuals were made either, other than that it's probably a single shader, and it's likely using sphere tracing.

Anyway, video available here: http://capped.tv/quite_orange-cdak|hq Binary available here: ftp://ftp.untergrund.net/users/ized/prods/cdak.zip (needs windows, and a very fast GPU)

Once again it's demotime! \o/

psonice's picture

Yep, early august is time for the 2nd major demo party of the year: assembly in finland. This is a massive party in a big sports arena, but it's mixed with a gamer/lan party (the sight of which fills the average demoscener with disgust, but hey it wouldn't be the same without them :)

So, on with the demos. I'll post links to the executables (mostly PC/Windows unfortunately), youtube videos (good for a quick scan) and high quality videos (MP4, large files, 720p, but well worth the download for the quality.. youtube's compression seriously KILLS some of these!)

First, the 'main event', the demo competition itself. The rules here are pretty open: it must run realtime on a current high end PC, and I think the size limit is 128mb.

Happiness is Around the Bend by ASD. This won the compo. 8 minutes of amazing work, great effects and art. Executable: http://amusic.gr/files/ASD%20-%20Happiness%20is%20Around%20the%20Bend.zip Youtube: http://www.youtube.com/watch?v=SQngoCBvq3Q Video: http://www.scene.org/file.php?file=/parties/2010/assembly10/vod/1193_dem...

Ceasefire (all falls down..) by Fairlight. Came 2nd. This is Smash's work, and is technically awesome as usual. Everything is rendered using particles.. millions of particles, with lighting, fluid effects and texturing, in realtime. Good artwork + music too. Executable: ftp://ftp.scene.org/pub/parties/2010/assembly10/demo/ceasefire_all_fall_... [warning: needs a VERY high end video card!] Youtube: http://www.youtube.com/watch?v=Grqb1aIa_4s Video: http://www.scene.org/file.php?file=/parties/2010/assembly10/vod/1185_dem...

Koiban by Satori. Came 7th, but it's not a natural party-friendly demo like the others so this is actually a very good ranking for this kind of demo. It's software rendered and needs a fast CPU (3ghz core 2 or an i5/7 is a good idea, the engine isn't yet threaded so multicore won't help). Satori do very cool psychadelic art stuff, the kind of effects we often make in QC. Executable: ftp://ftp.scene.org/pub/parties/2010/assembly10/demo/koiban_by_satori.zip Youtube (NOT recommended for this one, it just can't cope with the number of lines ;) http://www.youtube.com/watch?v=BVwY5D-NQiY&hd=1 Video: http://www.scene.org/file.php?file=/parties/2010/assembly10/vod/1195_dem...