Point instancing

[alexon]

Hi all,

I'm new to Houdini, and I must say it really rocks.

I'm trying to use the point instancing to animate some petal flowers, and I'm some problems

controlling my instanced geomtery.

First of all, the geometry has a vex shader I built with vops and a displacement as well.

If I'm scaling the geometry with pscale attribute, I can't get my shaders to follow the scale, I think I should use a rest position but I don't know where to set it (in my vops I'm already qassing restP as the input point for both bump and displacement).

Secondly, in Maya [ok, I'm a maya user] I can control the rotations of instanced object, both with velocity, position,.. or by custom attribute I set per-particles. How can I achieve this behaviour with Houdini point instancing?

Thanks in advance,

Alex

[Symbolic]

I am also trying to find a solution to the same problem.

Need help!

[aracid]

hey

the trick with the restP attrib is that u use the REST SOP to create that attribute(u do this in sops).

what this does is create an attribute that u use in vops, this is used as a reference for where the original unmodified geometry was.

u should be able to rotate the normals, i think using the rotate POP, just specify the axis and the amount.

also try looking at the resistance POP, thats cool for instancing too.

u can check ur results using the copy sop, so just copy ur petals onto ur particles. that will show u how the rotation is working.

hope this helps

[3dbeing]

I believe adding an up vector is helpfull in some rotation situations, combined with the normal, this will give you a constant triangulation for other computations.