Avalanche of falling books

[Juraj]

Hi,

how would you approach this type of shot? My task is to create simulation of falling books (up to 500).

So far I created two boxes which represent book, constraint setup is simple and simulation is fast and stable.

 

But now I am thinking about "upres" workflow. Basically I need to replace those simulated boxes with higher poly book model.

So far I had those ideas, but I am not sure how to implement them:

1. create a simple book rig and then somehow apply data from rbd sim to drive those instanced rigs (pros: much control above deformation using skinning, cons: too difficult and maybe not most efficient)
2. cut book into two halfs and then instance each half on simulated box and then bridge/fuse to undo cut (pros: seems quicker and simpler solution but I am not sure how to undo this cutting process)
3. wire capture & deform (cons: I tried early tests which resulted in weird deformations and it seemed to be too slow)

Any ideas how to approach this kind of effect?

 

Thanks,

Juraj

[loopyllama]

It really depends on how close you see the books, and if they are hard cover or soft cover.

If it was a mix of covers with a medium distance shot, I would be tempted to do a rbd sim first, of closed books. Then I would try to get 2 or 3 closed soft cover books going. Maybe based on cloth? Next I would build a system to control the mix of hard and soft covered books. Finally I would make a hinged rbd book with a super simple control rig: maybe there are 5 sections of pages all controlled with the same spline, and the chunks of pages separate based on the angle of the hinge, and wiggle based on the spline. I would sprinkle in a few hero books in the main sim. I would let the hinge drive the chunk separation, and use some noise to control the page wiggle. I would use metaballs and magnets, lag chop, noise, and hand animation to cheat the pages of these few hero books within the main working sim. For me, I would completely abandon the idea of simulating all the books and all the pages.

 

If you have an extreme close up shot it will be much more difficult because of the pages. Hopefully that is not the case.

 

Sorry I don't have a slick hip file for you. Maybe someone else can whip something up?

[Juraj]

Hi, thank you for your reply.

Soft covers are not necessary. It is good idea to create underlying layer of closed books. The project is cartoony so individual pages are not necessary.

 

So I may create three layers:

• closed books on the bottom
• on top books that can open (but only in half, or thirds - with hinge constrants)
• and finally few hero books (hand animated and it will depend on shot type)

 

But my implementation questions remains: how can I upres simulated books (2nd layer) from boxes? And how would you approach a book rig?

[loopyllama]

Basically, Option 1 from your list:

 

If you have an rbd box for the front cover of the book and an rbd box for the back cover of the book you can constrain bones/joints/lattice to where the box (book cover) meets the spine of the book. The rig could have 3 joints in the hierarchy: 1 root, 1 at the spine/front cover, 1 at the spine/rear cover. Adjust the weighting of the front and back cover, near the spine, on the high res book. Handle the pages however you'd like. Maybe they have a separate joint, maybe the book opens and some pages move with the front cover while the rest move with the rear cover, maybe they are driven by stiffer cloth.

 

An rbd from the sim provides translation and rotation, and passes that to the joints via constraints, which animates the book opening/closing through weighting.

 

Make a string of nodes that creates a book, and scales it to some random height, width, thickness, and adjusts the rig simple rig accordingly.