C4D TP Object Collision question

[Adam Trachtenberg]

Assuming you’re using a PDeflector node, you would have to set the collision type to “back” (or both if the emitter is already inside the text).

[Raul Velazquez]

Mr. Trachtenberg

Thank you for your help. I have attached below pictures of both my Xpresso Node Trees. For the Collision you said to add “Back” to the PDeflector Node. My question is what should I connect that to in the TP Object Collision Node? do I run it through P Pass?

Do I need to add “Back” to the Emitter too? Which in the case of the emitter my earlier question would also apply. Where do I add “Back” and what do I attach it too?

https://www.shihstudio.com/client/emitter.jpg

https://www.shihstudio.com/client/Collision.jpg

[Raul Velazquez]

Mr. Trachtenberg

I found what you meant by the back setting in the Collision node. Is there any way to have a more accurate response when they collide with the inside of the object? Some go through the object and others partially come though the object. Otherwise I have what I’m looking for.

Thanks for the help.

[Adam Trachtenberg]

You have a couple of options to minimize the particle geometry’s penetration:

(1) In the PDeflector node, with the deflector type set to “Object”, as in your screen shots, set the PDeflector node’s Offset Type to “Particle Size Travel”. Then experiment with the Offset value to achieve the best results;

(2) In the PDeflector node, change the Deflector Type to “Geometry”. That uses the actual particle geometry instead of an approximation to detect the collision. It only works with polygonal geometry — not generators or primitives.

[Raul Velazquez]

I tried Geometry for Deflector Type and it goes right though the object.

I have Collision type set to Back and Offset Type set to Particle Size Travel. I am using a simple Plane 20m Width by 20m Heigh with 5 segments Width and Height wise. Textured with a cloud I illustrated with an alpha channel.

Everything works fine with PDeflector set to Object and Collision type set to Back and Offset Type set to Particle Size. Even those as you know some particles show though the object or go through it.

My next question is if I have to go with the options “PDeflector set to Object” what values do you suggest for Particle Size Travel to use for

Variation 1,2 ? I have no idea what that would apply to in the way the particles move? Everything below that makes sense.

[Raul Velazquez]

I also wanted to add that Rigid Body Dynamic tags are attached to the object used in the particles and the Object its colliding with.

The Rigid Body Dynamic tags are in the original scene example I used to put this together so I’m using them also. I don’t know if they are still needed or not?

In the particle object the settings are:
Total Mass: 0
Rotational Mass:100%
Center X,Y,Z: 0
Include Children: checked

Collision Detection: Full
Elasticity: 100%
Static: 145%
Dynamic: 100%

Double-Sided: checked
Drag: 10%
Impact: 100%
Lift: 100%
Linear: 0
Angular:0

In the Text object (whats used to Collide with the settings are:
Total Mass: 0
Rotational Mass:100%
Center X,Y,Z: 0
Include Children: checked

Collision Detection: Full
Elasticity: 100%
Static: 159%
Dynamic: 100%

Double-Sided: checked
Drag: 10%
Impact: 100%
Lift: 100%
Linear: 0
Angular:0

Hope that helps you with any thoughts on the Geometry option not working for me.

[Adam Trachtenberg]

Regarding geometry type collision, as I said, it doesn’t work with primitive objects so you would have to make your plane editable. For object type collision, the offset is a function of the particle size, so it just depends how big your particles are. It’s sort of trial and error to get the right setting.

You don’t need the rigid body tags since Thinking Particles is handling the dynamics.

[Raul Velazquez]

I do have my model text editable. The only thing is that I have it transforming from a solid state to a crack open state using Morphs to transform from one model to the next which both are editable. Can that affect the way TP is calculating the particles position? Because when I switch to geometry like i stated before they just go right through it.

[Raul Velazquez]

Man I’m such a moron I read what you wrote and looked at my setup and realized that I didn’t make the object I’m using to for the particles editable. Deflector Type: Geometry works now. Thanks for the help. I think I can trouble shoot the rest.

[Raul Velazquez]

OK i have a question. I can’t seem to figure out why my particles are getting stuck to the surface of the text once they hit? I have bounce at 100%.