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Keyframe animations vs dynamic simulations

Posted: March 08, 2009
3d artist gallery Andyba
When it is more appropriate to use dynamic simulations instead of keyframe animations?

What ways there are to make the dynamic simulations more controllable?

What is the best way to combine keyframe animations with dynamic simulations?
Posted: October 07, 2009
Vultur
i'm asking myself these questions now, with a school project.

i'm trying to animate a car crashing through a fruitstand, and dynamics sofar seems terribly processor hungry. just to bang out a playblast takes forever.

i do have a lot of objects to be moving however, something like 50 objects to go flying. all quite low poly. i'm a bit confused as to why it takes maya so long to calculate these collisions, when game engines can do the same (albeit simpler) at will.

any suggestions?
Posted: October 07, 2009
3d artist gallery Andyba
I think that game engines use approximate geometries like bounding boxes or bounding spheres. While Maya tries to calculate the actual shapes.

Also some game engines may use the GPU for dynamics calculations, though I am not sure about this.

What do you mean when you say "quite low poly"? I would create really low poly objects and constrain the high poly objects to them so they follow the motion but do not take part in the dynamics calculation.
Posted: October 08, 2009
Vultur
Andyba wrote:

What do you mean when you say "quite low poly"? I would create really low poly objects and constrain the high poly objects to them so they follow the motion but do not take part in the dynamics calculation.

i have 3 boxes. the boxes are split into 6 pieces. each piece is a cube, so like 72 polys for the boxes. and the fruit pieces have roughly 20 or so polys.

how it is is, the boxes are broken up into pieces like a jigsaw puzzle to simulate splitting, and the fruit is sitting on the boxes. more fruit is inside the boxes.

the three boxes with fruit are close to each other, and i'm thinking the source of my slowdown isn't the number of polys i'm using so much, as the amount of collisions that are present between all the pieces. interesting in your solution of constraining high polys to low polys to simulate the effect. i will give that a try with the fruit and see if that helps me out any. what i really wish is that maya had a way to tune down the physics, as you can tune down render quality. would be great if you could get a "preview" physics run on objects. mayb there is one and i don't know about it.
Posted: October 09, 2009
3d artist gallery Andyba
What fruits do you have? I don't remember in Maya but in 3ds max dynamics there is an option to substitute spherical 3d models with a mathematical sphere so it will not consider all the polygons but will use a perfect sphere formula for calculation which should make it faster. May be Maya has something similar.
If you can post a screen shot of what you are doing it could clear things up for many readers.
Posted: October 13, 2009
Vultur
i have some screenshots i can upload. but the anti spam filter doesn't trust me yet.

i don't know if i can wait for 12 more dates. Ms. Spam is quite the prude!
Posted: October 22, 2009
3d artist gallery Andyba
Vultur, I think you can upload images to 3dmd servers. What you can't do yet is point to other images. i.e. use links.

Just use the Go Advanced button after you have entered the text in the fast reply form.

Please let me know if you have some problems.