Search found 463 matches

by Basroil
Mon Apr 18, 2016 1:28 am
Forum: General Bullet Physics Support and Feedback
Topic: [solved] softbody java native binding, btAligned problem
Replies: 8
Views: 3332

Re: softbody java native binding, btAligned problem

If you disable SSE you should have no problems (other than taking forever to do it), but if you keep SSE (which does help considerably), you'll need to ensure alignment within your compiler by other means. If it's not 16byte aligned, it might just flat out crash at SSE code
by Basroil
Tue Apr 12, 2016 3:10 am
Forum: General Bullet Physics Support and Feedback
Topic: Help for a thesis work
Replies: 4
Views: 1961

Re: Help for a thesis work

Hi, Is this high level of complexity due to the algorithm itself or to the model, choosen for the soft body? Thanks Bit of both, but mostly the soft body. For medical work you really need full FEM and feedback of that FEM result into your collision mesh. After all, without that feedback it's just a...
by Basroil
Sun Apr 10, 2016 2:53 am
Forum: General Bullet Physics Support and Feedback
Topic: Applied torque by angular motor?
Replies: 4
Views: 1979

Re: Applied torque by angular motor?

Have you tried using btJointFeedback ?
by Basroil
Fri Apr 08, 2016 4:55 am
Forum: General Bullet Physics Support and Feedback
Topic: Seeing Output of Program
Replies: 5
Views: 2286

Re: Seeing Output of Program

But when I debug, I get the above messages and then nothing happens, do I need OpenGL to actually visualize? How do I see the sphere falling onto a surface. I guess what I am saying is, how do I provide this code to an OpenGL program? In the long run, I have a OpenGL program with Spheres flying in ...
by Basroil
Wed Apr 06, 2016 3:36 pm
Forum: General Bullet Physics Support and Feedback
Topic: Seeing Output of Program
Replies: 5
Views: 2286

Re: Seeing Output of Program

Sounds like it worked properly. Try running the example browser next to see if that's closer to what you expected to see.
by Basroil
Tue Apr 05, 2016 6:15 am
Forum: General Bullet Physics Support and Feedback
Topic: Generating a navigation mesh in a static world.
Replies: 3
Views: 1878

Re: Generating a navigation mesh in a static world.

3D navigation maps/pathing are a quite difficult thing, sure you can't just pre-render a 2D node map of the scene to traverse with standard techniques? If you want to take the 3D route though, take a look at: http://ri.cmu.edu/pub_files/pub4/carsten_joseph_2006_1/carsten_joseph_2006_1.pdf https://ww...
by Basroil
Tue Apr 05, 2016 6:05 am
Forum: General Bullet Physics Support and Feedback
Topic: Shaping a world as a Cylinder
Replies: 8
Views: 4584

Re: Shaping a world as a Cylinder

I know this thread is old but I too was searching about this and wanted to note that this is incorrect for the sake of miss information Actually he was entirely correct, as a cylinder and cylinder hole are two very different beasts. [*]How do you define the collision surface? [*]How do you determin...
by Basroil
Mon Apr 04, 2016 2:05 am
Forum: General Bullet Physics Support and Feedback
Topic: Help for a thesis work
Replies: 4
Views: 1961

Re: Help for a thesis work

Yes, you'll need a new dispatcher and narrowband collision detector. Take a look at the default collision dispatcher and the hull-hull narrowband collision code, those should give you an idea of how to move forward Do note that this type of system is nearly impossible to implement in real time witho...
by Basroil
Fri Apr 01, 2016 2:39 pm
Forum: General Bullet Physics Support and Feedback
Topic: Accelerate time / timelapse
Replies: 4
Views: 2104

Re: Accelerate time / timelapse

Just call stepSimulation(duration,max_sub_step, simulation_step_size) as many times per second as you need, and do whatever control you need to between steps. Remember that the default simulation step size is 1/60s, so if you want a 1:1 simulation you'll need duration at 1/60 and need to call stepSi...
by Basroil
Thu Mar 31, 2016 6:23 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet stepSimulation using multicore
Replies: 1
Views: 984

Re: Bullet stepSimulation using multicore

Yes and no, lunkhound has a nice multithreaded application of bullet at https://github.com/lunkhound/bullet3 , but there are limitations (doesn't scale well if you have few islands). If you need more than that, check out the openCL Bullet3 work at the main github page, it also has some limitations t...
by Basroil
Thu Mar 31, 2016 6:19 pm
Forum: General Bullet Physics Support and Feedback
Topic: Accelerate time / timelapse
Replies: 4
Views: 2104

Re: Accelerate time / timelapse

On a 4-core machine I manage ~ 200 simulation seconds per second of real world time (in a very small simulation), so it's definitely possible :wink: The easiest way is to just throw out the GUI entirely and manually step the simulation as fast as possible in your update loop. If you MUST have the GU...
by Basroil
Mon Mar 28, 2016 2:25 am
Forum: General Bullet Physics Support and Feedback
Topic: How to know if my Character go up or go down a slope ?
Replies: 5
Views: 2084

Re: How to know if my Character go up or go down a slope ?

If you already know the slope why not just calculate the current position vs the slope normal? Assuming X axis is forward from the facing direction to the slope, a positive rotation in the y means up slope and negative means downslope. The entire implementation would require only a few matrix multip...
by Basroil
Sun Mar 27, 2016 4:08 am
Forum: General Bullet Physics Support and Feedback
Topic: Hinge Joint Limits
Replies: 3
Views: 1695

Re: Hinge Joint Limits

Thanks Basroil, that helps clear things up. One point of confusion for me was that Blender wasn't allowing the hinge to rotate at all, because I did not have the joint linked to another object. I was assuming that Blender would treat the joint as being linked to the world if you left the "Target" f...
by Basroil
Sat Mar 26, 2016 11:17 am
Forum: General Bullet Physics Support and Feedback
Topic: Drag force, skid
Replies: 2
Views: 1412

Re: Drag force, skid

Both things you're talking about come down to friction, so perhaps you'll need to enable anisotropic friction. Drag can also just be modeled as a linear damping on velocity in the direction the car is going, but you'll need to be careful about implementation or else you might get bunny hopping explo...
by Basroil
Wed Mar 23, 2016 3:44 pm
Forum: General Bullet Physics Support and Feedback
Topic: Hinge Joint Limits
Replies: 3
Views: 1695

Re: Hinge Joint Limits

An easy way to think of hinges are two separate axis definitions in local coordinates, one in the first body, second in another body (or world). The x-y plane of those two axes when viewed in the world frame is always the same, but the plane is rotated about z by some theta. Zero is when the two axi...