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I have a coiled rope that unwinds nicely when the rope is enabled. I want to have the rope reset to it's starting coiled shape every time I activate it. How to I reset the rope to it's original shape?

(13-02-2020, 12:18 PM)basilisk Wrote: [ -> ]I have a coiled rope that unwinds nicely when the rope is enabled. I want to have the rope reset to it's starting coiled shape every time I activate it. How to I reset the rope to it's original shape?

All you need to do is set the solver's particle positions/velocities to the ones stored in the blueprint. If you're using a rod (which makes use of oriented particles), do the same with particle orientations/angular velocities.

Only thing you need to be a bit careful with is converting the blueprint data (which is expressed in local space) to solver space. Like this:

Code:
void Reset(ObiActor actor)

{

        if (actor.isLoaded)

        {

            Matrix4x4 l2sTransform = actor.actorLocalToSolverMatrix;

            Quaternion l2sRotation = l2sTransform.rotation;

            for (int i = 0; i < actor.particleCount; ++i)

            {

                int solverIndex = actor.solverIndices[i];

                actor.solver.positions[solverIndex]  = l2sTransform.MultiplyPoint3x4(actor.blueprint.positions[i]);

                actor.solver.velocities[solverIndex] = l2sTransform.MultiplyVector(actor.blueprint.velocities[i]);

                if (actor.usesOrientedParticles)

                {

                    actor.solver.orientations[solverIndex] = l2sRotation * actor.blueprint.orientations[i];

                    actor.solver.angularVelocities[solverIndex] = l2sTransform.MultiplyVector(actor.blueprint.angularVelocities[i]);

                }

            }

        }

}

See:
http://obi.virtualmethodstudio.com/tutor...icles.html

Thank you, this works. But oddly, I am getting an error...

Code:
NullReferenceException: Object reference not set to an instance of an object

error at the line:

Code:
if (actor.isLoaded)

The rope shape is still being reset like I want even with this null error, so it works but I'd like to eliminate the error.

They way I've set it up is a public ObiActor myRope variable where I assign the rope GameObject in the editor, and when I want the rope to reset reset I pass myRope into...

Code:
void Reset(ObiActor actor)

Any idea why this null error is happening?

(13-02-2020, 02:54 PM)basilisk Wrote: [ -> ]Thank you, this works. But oddly, I am getting an error...

Code:
NullReferenceException: Object reference not set to an instance of an object

error at the line:

Code:
if (actor.isLoaded)

The rope shape is still being reset like I want even with this null error, so it works but I'd like to eliminate the error.

They way I've set it up is a public ObiActor myRope variable where I assign the rope GameObject in the editor, and when I want the rope to reset reset I pass myRope into...

Code:
void Reset(ObiActor actor)

Any idea why this null error is happening?

As far as your description goes, a null ref error in

Code:
if (actor.isLoaded)

can only indicate that "actor" is null. Maybe try using

Code:
if (actor != null && actor.isLoaded)

instead, if you plan on passing null sometimes? As to why is null being passed into the function, that's something I cannot know without looking at your actual code...

Sorry! Yep, it was completely my fault. Bad piece of code on my side.

Thank you for your help. ObiRope is great!

basilisk

josemendez

basilisk

josemendez

basilisk