I know Houdini is whole procedural. Ok.

But … what about operations with transformations. ICE has special nodes to do that. Node Editor in Maya also.

Houdini can do this inside VOPSOP with points but can not do that with objects. Let's look

examples

http://www.youtube.com/watch?v=bYrUTDcHSRI [youtube.com]
http://www.youtube.com/watch?v=fDPnunQtvjA [youtube.com]
http://www.youtube.com/watch?v=YklwlLcZNJg [youtube.com]

about matrix
http://www.youtube.com/watch?v=Z2EDqQto_hI [youtube.com]


my question is - can I build network math matix transformation objects? I asked that houdini users ( they did VFX to russian film - Stalingrad and I think they have greate skill in Houdini) They said me - Pyton Op only can do it and maybe I can do it inside vopsop using tricks. Is that realy?

Have you had a look at CHOPs and the MotionFX menu on all parameters including objects?

It's real easy to get in to these days. Take any object and using the RMB on say the transform parameter label and choose any of the presets in the MotionFX menu.


It all depends on what it is you specifically want to do?

I only know that chop works with channels. I need to learn to that. I have not found a node to work with matrix in chop. I am a novice user Houdini and do not understand a lot. In XSI I used matrix to do custom constraints.

Maybe Houdini has a different approach. I will learn Chop more. Thank you.

you can use the optransform() vex function to get the global transform matrix of any object to work with in vops, though You have to use a inlinevop for example to use the function.

Max Evgrafov
Is that realy?

Houdini whole kinematics system is based on nodes either with Fetch, Blend, Rivet, Sticky OBJs, or with Object, Transform, IKSolver etc CHOPs, so there was really no reason to make VEX based kinematics engine.

To addition to that expressions (both hscript and Python based) can be placed into objects' parameters making parenting with code easy.

Strictly speaking, you can use VOPs for objects' transformation also, but I don't think anyone uses that…

Here is a simple example file that shows how to use CHOPs to constrain one object to another. It uses CHOPs for everything but the null1 which is meant to be animated. Just a comp off of the first vid you posted, I think…

You can then add all kinds of different modifiers to this transform as well including Lag CHOP, Spring CHOP, Noise CHOP, etc.

thanks a lot !

I still think a vexbased kinematics engine would be great, as it would give us fine control.
vex is just a reference for the building blocks. right now pretransform, lookat and stuff like that is quite blackbox

SYmek

Max Evgrafov
Is that realy?

Houdini whole kinematics system is based on nodes either with Fetch, Blend, Rivet, Sticky OBJs, or with Object, Transform, IKSolver etc CHOPs, so there was really no reason to make VEX based kinematics engine.

To addition to that expressions (both hscript and Python based) can be placed into objects' parameters making parenting with code easy.

Strictly speaking, you can use VOPs for objects' transformation also, but I don't think anyone uses that…

sanostol
I still think a vexbased kinematics engine would be great, as it would give us fine control.
vex is just a reference for the building blocks. right now pretransform, lookat and stuff like that is quite blackbox

True, I also would love to have VEX kinematics, but staring from bones Most of what you do in parent/lookat/constrains business is doable with VEX, just it's not so slick. I think in time when VEX gravitates towards general purpose scripting it will eventually happen, for example with Vop OBJ :shock: