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THREEL
02-26-2016, 01:04 PM
Here's a test involving Bullet Dynamics. I will be making a much larger scene, if I can get the kinks worked out. Does anyone know what I need to do to make the rocks fly up in the air, spin, bounce , and come to rest in a more naturally looking way? Oh, also, I'd like to stop the rocks at the bottom from gyrating, before it's their time to be affected.

https://youtu.be/pz9HvZ_P9Js

Thanks in advance for any advice!

prometheus
02-26-2016, 02:16 PM
Here's a test involving Bullet Dynamics. I will be making a much larger scene, if I can get the kinks worked out. Does anyone know what I need to do to make the rocks fly up in the air, spin, bounce , and come to rest in a more naturally looking way? Oh, also, I'd like to stop the rocks at the bottom from gyrating, before it's their time to be affected.

https://youtu.be/pz9HvZ_P9Js

Thanks in advance for any advice!

too little information on the exploding force, what are you using..kinematic object or force.fields.and if so what type of force and force settings? and if you use a kinematic object, it depends on how you keyframed it, and also what density the pieces has.

THREEL
02-26-2016, 11:34 PM
I'm trying to upload the lwo and lws files for this, but for some reason it's not working. I browse and add files. It cycles for a little while. Then, there are no files there.

DAMAKERS
02-27-2016, 08:23 AM
Hello THREEL, try this
- reduce collision margin to something like 2 mm
- change the the shape to "Convex Pieces" (if not using lw2015) or "Mesh" (slow but works fine)
- increase the Friction 50%+ in both floor and rocks
- Also increase the speed of the collider so the rocks fly higher

Snosrap
02-29-2016, 07:06 AM
Oh, also, I'd like to stop the rocks at the bottom from gyrating, before it's their time to be affected. Best bet for this is to bring your simulation into Chronosculpt and fix it there. Actually I can't imagine any dynamics simulation not going through CS for clean up.

THREEL
02-29-2016, 08:09 PM
Here's the second attempt: https://youtu.be/EHSVqTsSXOw

Not perfect, but better. It took some doing, and much experimenting with parameters. There were times that the entire rock mass would spin around like Linda Blair's head on The Exorcist.

Here are some parameters. I had to use some of these numbers to even make it behave somewhat reasonable:

Dynamic
Type - Parts
Shape - Mesh
Collision Margin - 1"
Mass Dist. - Surface
Mass Spec - Given Mass
Mass (kg) - 85278960.0
Friction - 50%
Bounciness - Envelop: 0%, 30%, 5%, 0%
Linear Damping - Envelop: 0%, -10%, 0%
Angular Damping - Envelop: 0%, 10%, 0%
Glue Strength - Gradient based on distance using a ball shaped null
Null Obj. - Ball, 64'
Breaking angle and Distance - Unchecked

Tim, I need to check to see if I have Chronosculpt available to me.

Thanks!

Snosrap
02-29-2016, 09:50 PM
Look in your account. Use it to fix all your jittering. I just uploaded this as a full test of Bullet dynamics, Chronosculpt and the new camera matching tools in LW2015. Chronosculpt was used to stop the jittering that is associated with the dynamics when you are too lazy to dial things in inside of LW. It's really just easier to do with CS.


https://vimeo.com/157240124

THREEL
02-29-2016, 10:04 PM
Looks nice, Tim! Well, one thing's for sure, I'm not too lazy as I worked for several hours over 2, or 3 days trying to fix the issues I was having with this dynamics test. The weirdest part was when the entire rock started spinning around like a scene from The Exorcist. I wish there were some better tutorials that, actually, go over each individual parameter. I ma have too many pieces together as one item to make Bullet Dynamics 100% efficient. I must say that after several parameter changes I was finally getting some where. Also, I think it will work for what I have planned in the bigger scheme of things.

THREEL
03-01-2016, 09:38 AM
So, I'm trying to bring the MDD file into ChronoSculpt and I get an error that tells me the vertex count does not match.

THREEL
03-01-2016, 02:34 PM
I did get the cache to load. Where can I find good tutorials on the different functions, and what do I se to stop the jitter?

Snosrap
03-01-2016, 04:29 PM
First select the object you want to stop the jiggles. (In your case the rock) -- Press "s" and then click on the rock. Then use "Pin" to stop a particular part of the rock. You can then use the time slider to fine-tune where the rock stops and how with ease in and ease out controls.

THREEL
03-02-2016, 02:58 PM
This is my first attempt, after doing some work on the rock with ChronoSculpt: https://youtu.be/zw-kGW_IIpY I'm still having some premature fracturing going on. I wonder what the fix for that is.

prometheus
03-02-2016, 04:59 PM
Itīs Looking better now, though I am questioning the simulation speed, the non accurate physics speed makes it looks like just a dynamics test, maybe speed that up to more realistic physics speed?
Then again..if the slo mo thing is what you want?

premature fracture, go to see the doctor:D..well,..set the fracture object activation mode to sleeping, if you already have, you need to check the actual fracture pieces initially made, so that you do not have any offset on that when you fractured it.

Michael

BokadCastle
03-02-2016, 07:33 PM
In Bullet, the way to stop premature movement is to "activate on last key".
This tut shows how, at about 7:00 mins in, but the whole tutorial is relevant.
https://www.lightwave3d.com/learn/article/lightwave-115-forces-tutorial/

- - - Updated - - -

nice work Snosrap, keep 'em coming.

THREEL
03-03-2016, 09:55 AM
Here's the latest attempt: https://youtu.be/3jxzN6YQDAw

Tim: Thanks for the help with ChronoSculpt. I'm sure I have much to learn with the software.

Michael: Premature fracture, go to see the doctor, I got a big chuckle out of that. lol But seriously, I cannot be sure on whether, or not there is any offset. I do not believe I added any when I used fracture on the object. Also, I sped up the explosion and added some camera shake in my video editing software. Does that help any?

BokadCastle: Activate on last key seemed to help. Maybe, in the upgrade Newtek can modify this command. So, we can activate and deactivate on specific keys.

Now, I need to figure out how to "sweep" the rocks off the text in order to get a clean view of it without affecting all the other elements. Each object is its own individual lwo file. Is there a way to bring them all into ChronoSculpt at once, and then, how would I move the rocks from there?