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Tree Growth Animation WIP


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Not sure where the old thread is in the archives, if it's there at all. This is a render in V15 of an older project where I was trying to animate this tree growing from a sprout to a full grown tree. This is the full grown tree. This tree is actually a large set of smaller "branch" models assembled in the choreography. If I could assemble them as a single composite model it would be preferred, but I haven't figured out how to do that yet. I wish I could iteratively build the whole tree from a small number of tweakable branch models. Any ideas?

 

Here is an early test animation with a scaled down version:

 

Tree growth animation test.

 

And a closeup:

 

Tree growth closeup.

 

Image attached is the project render in V15. Wahoo! It works without rendering artifacts!

TreeAnimation01.jpg

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What ever process you're using, it looks like it's working well. I'm not sure what you mean by "iteratively build the whole tree".

 

In the first test animation the first stages looked very like a trunk model was just scaled up. If you could get some root movement in there as well it would be all the better for it. Even some concrete cracking would be a nice touch. Also, some offsetting of stages would be great.....such as all the leaves not growing on the same frame.

 

What did you do in the second animation? Animate the cps in the chor? I love the first winding growth of the branch.

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Just an idea: why don't you create the tree in one model, and rig every branch? You can add a scale bone and constrain the length of every bone to the length of that bones. Now, if you animate the length of the controller bone, the tree will grow. And you can create an additional action to make the branches shake while it's growing.

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What ever process you're using, it looks like it's working well. I'm not sure what you mean by "iteratively build the whole tree".

 

Just an idea: why don't you create the tree in one model, and rig every branch?

 

The tree is actually a set of models: one "trunk" model and a set of "branch" models of various sizes. The branch models are constrained to the spline that guides the trunk growth when the tree is assembled in the choreography. I did it this way because the overall workflow was more efficient. Tree parts are simple, but there are so many of them! Coordinating the animation of all these parts was the real time killer. Easier to set up a "branch" model with it's own action and then replicate it. I change the shape of each branch by altering the splines that define it's shape.

 

If I could do this iteratively to build a model I could do this in a single model. Otherwise a single model would require me to animate every single component--many hundreds of them.

 

The model's animation is guided by a set of splines that define the final form of the tree. The basic building block is a spline path and a simple tube with a bone asigned to each spline ring of the tube. The bones of the tube are constrained to follow the path. I set up a set of sliders to control the position and scale of each bone/ring. An overall slider control controls the whole set. I build a branch by constraining the bone of each individual spline path to a point on the spline path that supports it in the tree. As the point in the "growth" of the supporting branch reaches the point where a new branch is located, the new brach's visibility is turned on and it starts growing. This all mimics the fact that tree growth happens at the end of the branches--once the branch form behind the growth at the tip is established, it keeps it's shape and just thickens over time as growth rings are added. Simple scaling of parts does not work, since that is not how a tree actuall grows. (That being said, I actually cheat at the last step by scaling the leaf clusters--but in that case it looks natural enough to work. Another compromise is that the tube stretches along the spline path, so the bark texture flows with it--in a real tree the bark stays put and just thickens.)

 

So, if I could build a "composite" model from a set of smaller models, with all the constraints and controls remaining intact, I could build it as a single model instead of having to assemble separate branch models to make a tree in a choreography.

 

It would be great if I could export what I animate in the choreography as sort of a "model group" with an overall animation control, so that, even though it is not a model, you can import it back into a different choreography as though it were a model. That might be more practical than an "iterative" model feature, since it would group a set of actions with the set of models.

 

In the first test animation the first stages looked very like a trunk model was just scaled up. If you could get some root movement in there as well it would be all the better for it.

 

Yes, I need to work on that a bit to make it more natural looking. In reality, like branches, roots grow from the tips and thicken. In this case I should probably animate the shape of the spline rings at the base, not just scale them.

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I'm thinking assembling in an action with the trunk as a proxy and the branches as action objects. But if multiple models can be used in a pose, that might be even better. I want to use the whole set as though it were only one model so I can use it in multiple instances (9 if I can manage it), rotating the tree a bit so it will effectively look like a different tree each time.

 

Another option might be to render the tree in a separate chor and fake the multiple trees as flat video images (that will cast shadows) since they will be in a long, extra wide shot of a city block with nine brownstones in view. The end product is the important thing, so any effective short-cuts will be appropriate.

 

I used similar tricks putting the "Plateau of Leng" image together for the "Lost World" contest last year, but this is more complicated being an animated sequence.

 

Basically a brother and sister will be planting seeds along a city block and the trees will magically grow up as they work their way down the block.

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The animation is in the works! Tripped over a couple of querks in the import to V15. Don't know if I had the choreography length set wrong in the original, or it imported with a default length, but the imported project had a choreography length of 5000+ frames, rather than the intended 300. On top of that I did not notice that when I played out the animation, it only showed frames at large steps. The last frame in the playback was the last even step and the last frame of the sequence did not show--so the pose sliders that would show 100% only showed ~94% which corresponded to the last playback step. That threw me off and made me think the choreography relationships were messed up. Nope! Just a querk in the playback. Once I figured that out things have gone smoothly.

 

I still have the small branches to set up, but once that is done I'll do a test render of the whole growth from seed to fully grown tree.

 

So far so good!! :D

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