Is Cheetah capable of doing this?

Is Cheetah capable of doing this?

Dear all,

I apologize but I am really in need of doing one specific thing and I am afraid that without your help I will not have the time to find out if Cheetah is the appropriate tool for me. I am a researcher and would like to create two animations because they would really help getting my point across to a larger audience on a conference.

Problem 1)
I need to create an abstract tree-like shape from some half-translucent glass like material which when progressing upwards has one common root which branches in two branches one of which branches in two again etc. In the upper part of the diagram I would have four terminal branches which are connected in a tree-like fashion as described above.
Here comes the catch. The branches should be 3D models and tube-like rather than just flat lines, and have a wall thickness greater than zero.
What I would like to create is an animation that lets me view the tree from one side as described above and then twist it 90 degrees towards me so that the result of this I would be looking at four ellipses (i.e. the tubular branches cut in an oblique angle) plus some information from the connections from below which result from the fact that the material should be translucent.

Hard to imagine? Have look at this, slightly more complicated tree, but it gives you an idea what I am talking about, at least roughly.
tree.gif


Problem 2) this problem needs an earth with a texture mapped onto it to begin with. I was amazed that this procedure seems to be so intuitive and easy in Cheetah (judging from the tutorial). The problem is, it does not work for me. It starts to go wrong when the tutorial says "Notice that we already get a preview of our material in the material browser."
The texture never shows up in preview and neither does dropping the newly created material onto the ball in the objects browser do anything. The path to the image is correct, but i am stumped.
My problem is more complicated than this but without being able to create a representation of the globe first there is no point in giving more instructions.
I would be very grateful if someone could help me out on this one, even if the answer were a resounding "no, it's not possible, go look elsewhere". The conference is soon-ish and I thought of the visualization just now.

Thanks for your help
Prion

PS: I am running Cheetah 3.4 on a Powerbook 1.67 G4 with 2GB of RAM if this helps
 
Last edited:
Problem 1)
I need to create an abstract tree-like shape from some half-translucent glass like material which when progressing upwards has one common root which branches in two branches one of which branches in two again etc. In the upper part of the diagram I would have four terminal branches which are connected in a tree-like fashion as described above.
Here comes the catch. The branches should be 3D models and tube-like rather than just flat lines, and have a wall thickness greater than zero.
What I would like to create is an animation that lets me view the tree from one side as described above and then twist it 90 degrees towards me so that the result of this I would be looking at four ellipses (i.e. the tubular branches cut in an oblique angle) plus some information from the connections from below which result from the fact that the material should be translucent.

Here is a very rough sample of what I understood you want. Hopefully with this, you should be able to get your full animation. Otherwise, let us know.
There are certainly other ways to do it and other users might come up with better ideas.
Just run the animation after unzipping/opening the file.
 

Attachments

  • Test.zip
    17.1 KB · Views: 392
To answer the first question. What you want should be relatively easy using an animated boolean. If you're new to 3D in general what I've just said is complete nonsense but I've attached a basic example.
The second question is a little harder to answer because the tutorials are a little out of date but the basics are all there you just need a little help understanding what's going on.http://www.antialias.me.uk/test.mov

Andrew:)
 
The vbulletin forum software just decided to descard my answer, probably due to a timeout :cry: I need to type faster then...


I can watch the animation, Francois, but you are trying much more than I am really trying to accomplish. Assume we are just looking at a subset of the tree, including only the labels lizards, snakes, crocos and birds and the branches leading to them. For the sake of my explanation please also assume that this tree is standing upright on a table and is made of rather thick tubes. Your eyes are level with the table.

The animation step involves only this: The tree slowly falls towards you so that in the end it lies flat on the table. What you would see then is the crossection of the tubes, in this case four of them, their form would be small ovals because they have been cut in an oblique angle. Depending on the translucency of the material, one would also see two faint ovals uniting the two leftmost small ovals and another uniting the two rightmost. That's it, really.

Thanks for your help, it is much appreciated but I am afraid I will be able to go through the documentation only after the conference when there will be time. For now I will have to lifve with what I manage to get done with your help.

Thanks
Prion
 
the second part of m answer (trying to keep up with vbulletin's nervous stopwatch):
I found that applying a texture to the surface of a ball will sometimes work and sometimes not. The bad thing is that I haven't found a rhyme or reason to this. I can repeat the exact keystrokes and if I just do it often enough, it works - that's the bad news. The good news is that when it works it workds really well. Hopefully I will be able to post an example tomorrow.

Until then I hope you can help me out with my first problem, this one is more urgent.
thanks again
Prion
 
Hi,
applying a texture to a ball object should always work. Did you use the ball primitive from Cheetah3d or did you import the ball form an external file?

How much RAM does your graphics card has? I've you only have 8 MByte such a behaviour could happen. If you have 16 MByte or more it should always work.

Bye,
Martin
 
the second part of m answer (trying to keep up with vbulletin's nervous stopwatch):

Sorry for the problems. :oops:

I've recently updated vBulletin to version 3.6. Before I've never heard about that problem. Does anybody else encounter it.

I can't see a stopwatch when I write a message. Did I miss something. Can I change that in vBulletin?

Bye,
Martin
 
Hi Martin,

the Gaphics card in this Powerbook has 128MB or so. After many attempts I thought that there was a difference between generating a ball using the
Objects-> Polygon -> Ball
route versus the "Add Polygon objects to scene" -> Ball

But the problem occurs irregularly with both methods of creating the ball. As I said, sometimes I have to repeat the steps three or four times using the exact same keys until it works. When the Ball in the Materials browser shows the texture I want to use, it will also work when assigning the material to the ball in the objects browser.

Regarding the lost posting of mine I cannot say what exactly caused it. After writing my response and hitting the submit button, there was a vbulletin message popping up on the screen stating that I was not logged in (which I definitely was, otherwise I couldn't have started typing). Unless there are many others experiencing the same problem, I wouldn't be too worried if I were you. It was merely a little annoying, that's why I was trying to avoid the second time by splitting my response in two, there was no actual stopwatch appearing on screen.

Even though it is a bit hit and miss, my second problem is solved more or less, but does anyone have a solution for the first?

Thanks
Prion
 
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