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 ranaazeem03-08-2012, 06:03 AMHey Guys, Anybody can suggest a mesh Generation Algorithm? Basically generate quads out of curves?. NOT to mention Fast? I've come across some. But ofcors experienced TDs can suggest something better for me(moreover i am curious). I have more specific needs than just curves, i.e, read the particle instance and proceed accordingly. Any help would be much appreciated guys. Best Regards Azeem
ThE_JacO
03-08-2012, 07:33 AM
What do you mean with generate quads out of curves?
High order surfaces operations from curves are normally done by generating the surfaces and then deriving quads out of their parametrization.
There is hardly much algorithmic complexity, unless you go into even higher orders for trims and filleting, into that, the challenge is usually drawing the limit surface efficiently.
And if you already found and understood something, provide a link and details and maybe an explanation of what you find unsatisfactory with that solution.

As it stands the question doesn't make a lot of sense :)

ranaazeem
03-08-2012, 12:34 PM
What do you mean with generate quads out of curves?
High order surfaces operations from curves are normally done by generating the surfaces and then deriving quads out of their parametrization.
There is hardly much algorithmic complexity, unless you go into even higher orders for trims and filleting, into that, the challenge is usually drawing the limit surface efficiently.
And if you already found and understood something, provide a link and details and maybe an explanation of what you find unsatisfactory with that solution.

As it stands the question doesn't make a lot of sense :)
My apologies if i am not making a lot of sense here.
Basically i am trying to implement a system of art directable tree generation tools. And i am following a paper presented by Disney at Siggraph 2010 (Link (http://www.disneyanimation.com/library/tangledProcTrees.pdf))
They wrote something called skeletor. which can generate mesh out of a system of hierarchical curves(trunk, branches, twigs ). There will be branching and stuff. So i suppose that I've got to implement a mesh generation algorithm that can read that hierarchy of curves.
Basically, a particle marcher would be taking care of branching.
So the mesher have to read "lifetime" from the instance of particles so that it can adjust the diameter of the branch, its working on.
So I stumbled upon something like this (http://visgraph.cse.ust.hk/projects/skeleton/).
I am in planning/Graphing/design phase. So my main goal is to search for methods/options right now.
Do i make any better sense now?
Let me know if i am getting it wrong somewhere.
Azeem

ThE_JacO
03-08-2012, 11:07 PM
It makes a lot more sense now, yes.
It's basically the problem of meshing user directable L-Systems.
Sadly, it's well outside the domain of anything I've done before, so I can't help with it, but you now stand a better chance that others will ;)

ranaazeem
03-09-2012, 07:11 AM
No problem :)
I really appreciate your quick response.
Hoping to get some help here.
Thanks

Edit:
Just to get the discussion going. I realized that Lsystems wont be enough for the art Directed/Stylized look required. Yeah Lsystems are really good at generating a lot of iterations of trees quickly. But i agree with the people at Disney that it IS a little too parametric. I am not sure if i am using the right word here. But Lsystems may be, are a little too rigid for the main focus of the system. But as i said, its a suite of utilities(a small tree pipeline). So obviously Lsystem generation will be a part of it.In a way that the particle marcher can compute growth on the supplied basic curves for the trunk using Lsystems. Pardon my little knowledge, but i am aiming to design the data flow in a way that every tool can act as a primitive. And one can design the tree in kind of layers. Basically loop back and forth. If that's desired.

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