Hi All,

The problem I had with the attached scene was the different orientation of particles between the ones that moved and the ones that didn't (a 90 degree flip). I think the problem is solved for this simple test scene but i can see it could cause problems with something more complicated.
So is there a better way to orient my points with Z pointing in the direction of the surface normal, so when velocity takes over i don't get a flip.

cheers

Craig.

set the velocity in source to then stop with the state pop.
un-stop them with your animated group.

thank you very much cpb!

I went through your network and just want to make sure i am understanding it. The color ramp inside popnetwork is used to control the pushDown force and also gets imported into the vopsop. The vop sop that pipes into the copy sopy is just a blend for the geometry to either follow the original particle normal direction (value 0) or to follow the particle velocity direction(value 1) . And the import attributes inside the VOP SOP are just pointing to whatever is plugged into the vop sop(so first context is 0 second context 1 ect).

I am very new to houdini but it really is fun to learn.

thanks again

Craig

Yep that's correct. Using colour is handy because it is always accessable when moving points between pops and sops (or even within either).
Otherwise you'd have to use a point() expression to re-create the attribute.
Anyways the blending part is irrelevant; I had added it before re-reading your question properly!
The trick was to set velocity and stop the particles.

Im glad you never read my original post properly as you solved my original question with an extra bonus.

I am glad you added the blending part as it opens new doors as i'd not looked at the vop sop before.

I've recently discovered how handy color can be for jumping between pops and sops.

Im starting to pickup going between dops,sops and pops and it just amazes me the sort of control and flexibility you get with only a small amount of knowledge.

thanks for your time

Craig

Just a bit of in-fill data on vop sops, hopefully it won't be confusing. You are doing well with this stuff and understanding what a vex network will help later on.

No data that is input into the top of a vop sop is actually passed into the underlying vex network. The vex network is establishing the parameters the vop sop will recognize and providing “rules” for how that data is filtered as it passes through the vop sop. The vex network is a true programming environment and the code in there is compiled and passed up to the vop sop. You can see the raw code in the vex network by MMB on any of the node headers.

thanks probbins,

I think thats how I was looking at it because I noticed you had to import params.
Did nt know you could view the code with the MMB though!

Craig