Spring Joint

Report any bugs here and we'll post fixes

Moderators: Sascha Willems, Thomas

Spring Joint

Postby AntonSynytsia » Wed Jun 04, 2014 8:17 pm

Can anyone give me a good reference to a custom spring joint?

Edit: Sorry, should've posted this in General Discussion :roll:
AntonSynytsia
 
Posts: 193
Joined: Sat Dec 28, 2013 6:36 pm

Re: Spring Joint

Postby DashW » Fri Sep 19, 2014 12:54 pm

I would appreciate this myself. Clearly it can be done, since it's been implemented in this sandbox application (written in Delphi?! ten years ago?!), but of course it doesn't come with any source code.

http://www.saschawillems.de/?page_id=80

For the moment, I'm going to try implementing the mouse-pick functionality from Newton's sandbox as a custom joint. I'll let you know how it goes.
DashW
 
Posts: 5
Joined: Sun Aug 03, 2014 4:45 am

Re: Spring Joint

Postby arkeon » Fri Sep 19, 2014 6:48 pm

Hi,

to make a spring joint, use a customSlider joint and add this code in the submitConstraint callback
Sure you you have to define m_useSpring, m_springStrength and m_springDamping in your joint class.
Code: Select all
  if (m_useSpring)
  {
    NewtonUserJointSetRowStiffness(joint, 0.8f);
    NewtonUserJointSetRowSpringDamperAcceleration(joint, m_springStrength, m_springDamping);
  };
arkeon
 
Posts: 261
Joined: Sat Sep 13, 2014 5:25 pm

Re: Spring Joint

Postby AntonSynytsia » Sat Sep 20, 2014 4:49 am

Thanks arkeon, I will implement this piece of code.
AntonSynytsia
 
Posts: 193
Joined: Sat Dec 28, 2013 6:36 pm

Re: Spring Joint

Postby AntonSynytsia » Sat Sep 20, 2014 5:05 am

@DashW Thanks for informing me with the sandbox. Played it, looks fun! Quite similar to SketchyPhysics (if you know what I'm talking about).

Speaking of the pick and drag tool, Newton Demos 3.13 uses force and torque technique, rather than the custom joint like in Newton2. I don't know which one would be a better solution though, a constraint or a force and toque technique.
AntonSynytsia
 
Posts: 193
Joined: Sat Dec 28, 2013 6:36 pm

Re: Spring Joint

Postby manny » Sat Sep 20, 2014 6:09 am

You can also use:
Code: Select all
NewtonCalculateSpringDamperAcceleration
and apply the force manually.
http://www.instaLOD.io - InstaLOD - State of the art 3D optimization
manny
Site Admin
Site Admin
 
Posts: 131
Joined: Tue Feb 11, 2014 6:49 pm

Re: Spring Joint

Postby Julio Jerez » Sat Sep 20, 2014 6:33 am

using the force is simpler, but gives you less control.

I would go for the force method. BTW I made some changes to how the force is calculated,
before the force was calculated in the demo, now the relevant part of the code is a function in the PhysicUtil.cpp file.
Julio Jerez
Moderator
Moderator
 
Posts: 12249
Joined: Sun Sep 14, 2003 2:18 pm
Location: Los Angeles

Re: Spring Joint

Postby AntonSynytsia » Sat Sep 20, 2014 12:39 pm

Thank you, Juleo.

I will implement it in my wrapper.
AntonSynytsia
 
Posts: 193
Joined: Sat Dec 28, 2013 6:36 pm

Re: Spring Joint

Postby manny » Sun Sep 21, 2014 5:55 am

sovled+locked.
http://www.instaLOD.io - InstaLOD - State of the art 3D optimization
manny
Site Admin
Site Admin
 
Posts: 131
Joined: Tue Feb 11, 2014 6:49 pm


Return to Bugs and Fixes

Who is online

Users browsing this forum: No registered users and 6 guests