Gravity and VEX Expressions In the DOPNET?

[Paint!]

Hello once again.

 

Following another tutorial and I've hit a bit of a snag. The original purpose was to have particles emitted from the normals of some separate geometry. I used the Point SOP and Attribute VOP to create my normals and fed them into my v.

 

When it came to the dop network I used a POP wrangle and the function

 

@v= -@N

 

 

This gave my project the ability to emit from the normals. However now gravity won't effect the particles? I've scoured for different VEX expressions (which I still am struggling with since there isn't any decent tutorials that cover them.)

 

Anyone have any ideas? Have I over complicated something?particle_emission_along_generatednormals_via_popwran_attrivop.hip

[Hudson]

Hello!

Btw, I think you forgot to attach the "sprinkler.bgeo".

 

Anyhow the only problem is that you are overriding your particles velocity by (@v= -@N;) all the time since the particles inherit the N form the source and it will be constant.

To avoid that I usually create a "Birth group" (found in the POP-source under the Birth-tab). Now you can choose that group on your "popwrangle1" node. So the particles will only get that velocity once spawned (That is the only iteration the particle will be included in the birth-group).

A simpler way of doing what you want to achieve would be if you used a pointwrangle-SOP with the same code  (@v= -@N;)  on your source before DOPs. And adjust the "inherit velocity" in the POP-source node under the tab "Attributes"

Good luck!