Links, research, etc.
Here’s a collection of what I have and am looking at, time to analyze and document it all properly.
Real-world building demolition examples:
Low res videos, but still kind of useful
http://www.implosionworld.com/cinema.htm
Entire article on building implosions - lots of info.
http://www.howstuffworks.com/building-implosion.htm
It seems that large-scale demolition basically comprises of a few base layers being disintegrated (or at least the main support beams at this height). This is then followed by gravity pulling down the remaining floors, shattering them from the impact and their weight. This could also be due to severely unstable ground floors, or some kind of explosion. The actual falling down of the building is really a chain reaction from an initial explosion.
Implosions on Vimeo:
-this one is quite a good example of a very controlled demolition - the explosions inside on the support beams can be seen during the first explosions, followed by the base being blown apart to let the building collapse. Had the support beams inside not been destroyed first, it may have fallen in one chunk or sideways. This undesired effect might be more of what I’m after - a less controlled demolition.
-again, internal explosions, on the support structure. Interestingly enough the base can’t really be seen to be exploding on this - it almost implodes from the inside.
- in this the base floors have literally been taken away, leaving only the support beams. These are then demolished using explosives, with the building falling down section by section. What’s also interesting to note is the way the chunks fall down - metal reinforcing keeps some pieces together while the supporting structure breaks.
-another example of internal explosions, moving towards the outside, then leading to a base explosion and subsequent collapse. This video might be quite useful for dust cloud reference too - there’s a definite time when it emerges with debris etc.
Real-world explosion examples:
-bottle is shot by a bbgun - note how the glass doesn’t shatter uniformly, (smaller pieces near the point of impact) and leaves cracks around the impact zone.
-again, the entire object isn’t completely broken - only at the point of impact, which then spreads (depending on the force of the impact)
-although this is just an apple, the explosion is still useful to observe - especially regarding the variance in size of the chunks thrown outwards. I’ll have to keep this in mind for my explosions - possibly generate small chunks using particles while calculating the movement of the bigger pieces via dynamics.
Real-world stress points:
Already outlined in the aforementioned article - it’s the central support beams, usually made of steel.
http://www.howstuffworks.com/building-implosion.htm
Previous dynamics implementations:
Arr, there be no such thing that I could find…
Alternative dynamics systems:
Bullet physics, and Maya Dynamica plugin: (Open source)
http://bulletphysics.org/wordpress/
http://bulletphysics.org/mediawiki-1.5.8/index.php/Maya_Dynamica_Plugin
Blastcode (Costs, only works with nurbs)
Pulldownit (Costs, no support for fields in free version)
http://www.pulldownit.com/download.php
In the end I chose bullet, due to it being open source and mentioned in an interview with one of the VFX artists who worked on 2012, which can be found here:
http://features.cgsociety.org/story_custom.php?story_id=5368
Scripts:
http://www.creativecrash.com/maya/downloads/scripts-plugins/c/search?search=shatter&x=0&y=0
dg_voro_py 1.0.0 seems to be the best one, as the shatter can be controlled using locators to pinpoint parts of the shatter. It also includes a script to convert particles to locators, which makes for an easy way to create randomized, but slightly controlled shatters (using various fields on emitters etc)
Particle Emission
—-Still need to research, further down the pipeline
Technical Limitations
—-Testing this today
Particle Generation for Smoke Effects
-I’m using Maya fluids for this, as it can create more convincing, 3D smoke, instead of using a sprite-based system and particles. An excellent example of Maya fluid smoke can be seen here:
http://www.youtube.com/watch?v=cjxfnvWrOPY
Instancing Geometry with Particles
http://caad.arch.ethz.ch/info/maya/manual/UserGuide/Dynamics/AdvTopics.fm5.html
Very useful for debris - a small collection on pre-modeled chunks could then be instanced to a few particle emitters.
http://www.tutorialized.com/view/tutorial/explosion-using-particle-instancer/38905
Probably the most pertinent tutorial on the subject - randomly selected objects from a group of chunks, emitted with gravity…
Particle Control
http://www.wonderhowto.com/how-to-create-particles-collision-objects-maya-215917/view/
Collisions, etc are covered here. Will be good for making chunks hit the ground, etc.
Compositing
Still to be researched…
Demolition via Dynamics, Particles, Fluids, and After Effects.
