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Oldcode
01-04-2015, 11:36 AM
Hi,

I'm trying to do a shot where a ball inside of a tube grows and deforms the tube. Yes, I can do this with Effector, but its more complicated than that.

Until recently, whenever I need an effect of this type, I've been using ClothFx, but as we all know, ClothFx is slow and buggy. It crashes or the simulation fails 9 out of 10 times. I got sick of that so I'm looking into using Bullet. I've watched some of the tutorials and got the basics down, but there's one problem. Only the front facing polygons (the directions of the normals) seems to react to another dynamic object. I need to render the front facing polygons while the back facing polygons are used by Bullet.

Is there a way to make so an object will collide/interact with both sides of the polygons in Bullet?

In ClothFx, you can choose either Front Facing, Back Facing, or both sides of the polygons to interact with. I've not been able to find any such control in the Bullet properties.

126404

Is this possible?

Thanks in advance,

MG artist
01-04-2015, 12:23 PM
You could make a flipped copy of the object, that will not be rendered ( uncheck from the scene editor ) use bullet on it and metalink the original object to this one.

Oldcode
01-05-2015, 03:08 PM
Thanks MG,

I have thought about doing something along those lines, but it really would be better if you could just say, hey Bullet, please hit this side instead of that side.

What is a metalink? I've never heard of that one.

Thanks again,

ernpchan
01-05-2015, 10:25 PM
Do you a search for metalink on YouTube. It allows you to deform an object based on the deformation of another object.

Oldcode
01-06-2015, 11:17 AM
Thanks! I had never heard of that before, but it looks really cool. :D

ncr100
01-07-2015, 02:43 PM
OT but loosely related to Metalink - LW has a _lot_ of displacement plugins. Just realizing this as I'm feeling stability in my sea-legs with the program. Heck bones seem like essentially a suped up displacement plugin.

Ryan Roye
01-07-2015, 03:39 PM
Regarding metalink, never, EVER use the nodal version unless they fix it in a version past 2015. It may work when there are only 1-2 objects in the entire scene, but any more than that any it becomes unusable and unfixable, even knowing about "item shuffling" in the classic scene editor.

Oldcode
01-07-2015, 04:35 PM
Thanks Ryan,

I just saw the You Tube video where they talk about using the nodes.

https://www.youtube.com/watch?v=DRBY0vQmsJc

Seemed like a dream come true until your warning. I'm working on a jungle scene and was thinking of using this technique to make a lot of dangling vines.

Just saved me some frustration! :D

Cheers.

Every4thPixel
01-08-2015, 02:09 AM
Regarding metalink, never, EVER use the nodal version unless they fix it in a version past 2015. It may work when there are only 1-2 objects in the entire scene, but any more than that any it becomes unusable and unfixable, even knowing about "item shuffling" in the classic scene editor.

Do the Dpkit ones have that problem too?

Ryan Roye
01-08-2015, 05:48 AM
Do the Dpkit ones have that problem too?

The DPkit one is better, it just seems to crash a lot and I wouldn't trust it in production either.


I'm trying to do a shot where a ball inside of a tube grows and deforms the tube. Yes, I can do this with Effector, but its more complicated than that.

There's actually a nodal example of this in the LW3DG 11.6 content files. To save you time searching for it i've attached it here:

126482

I'm not really familiar with nodal displacement tricks, but theoretically you could adapt this to a different scene using different models.