ArcRotateCamera checkCollisions set to true locks up camera

[JLHolmes]

Hey guys... it's been a while, but things have been going pretty smooth with BJS.

That is, until I upgraded to 3.0. My scene just up an disappeared! Digging into it, I found that it was when I set checkCollisions to true, the scene for that camera would just lock up the camera.... unable to move it at all.

So....

sceneState.camera = new BABYLON.ArcRotateCamera("ArcRotateCamera", 0, 0.8, 1000, new BABYLON.Vector3(0,0,0), sceneState.scene);
sceneState.camera.speed = 5;
sceneState.camera.checkCollisions = true;
sceneState.camera.ellipsoid = new BABYLON.Vector3(2, 5, 2);
sceneState.camera.upperBetaLimit = Math.PI/2;
sceneState.camera.wheelPrecision = .1;
sceneState.camera.lowerRadiusLimit = sceneState.togScene.gridSize * 2;

Fails... but...

sceneState.camera = new BABYLON.ArcRotateCamera("ArcRotateCamera", 0, 0.8, 1000, new BABYLON.Vector3(0,0,0), sceneState.scene);
sceneState.camera.speed = 5;
sceneState.camera.upperBetaLimit = Math.PI/2;
sceneState.camera.wheelPrecision = .1;
sceneState.camera.lowerRadiusLimit = sceneState.togScene.gridSize * 2;

... is just fine.

Thoughts? Did I miss some other setting or change with regard to moving to 3.0? (Actually, v3.1-alpha)

[RaananW]

Hi @JLHolmes,

do you think you can reproduce it on the playground?

Also - are you using the workers-collision, or the native collision?

[JLHolmes]

I'm trying to repo it in the playground... it does not seem to happen in simple scenes... only when there's an object much larger than the camera's radius.

How do I determine what type of collision is being used? Well... since I have not done anything special to pull in collision I assume I'm using native.

[RaananW]

I assume so as well

Are you sure you are not stuck in a mesh when the camera is created? try changing the radius to something much larger and see if it works. 

[JLHolmes]

Yep... tried that. It doesn't matter how far out I set the radius. The camera is still locked in place. I'm trying to simply the scene to get at it more.

[Wingnut]

Hi guys... sorry to interrupt.  JLH... are you using a ground?  Is the ground set .checkCollisions = true?  Was the ground created with .createGroundFromHeightMap?

(thx)

I did a little experimenting... http://playground.babylonjs.com/#NAM2N8#1

I am unable to reproduce the stuck camera symptom, so far.  JLH's camera settings are in lines 55-61. 

I added two badly-Wingnut-coded funcs at the top... that I have used for other projects... .showEllipsoid() and .setEllipsoidPerBoundingBox().

After activating them in the lines 88/89, I realized they were failing...  particularly the .refreshBoundingInfo() in line 6.

Anyway, I learned very little... still testing... but in this version, line 98 reports (-infinity, -infinity,-infinity) and that concerns me. 

Activating line 91 is still causing errors, unless I ALSO activate line 90.  hmm.

Code:  https://github.com/BabylonJS/Babylon.js/blob/master/src/Mesh/babylon.mesh.ts#L622

That's all I have.  I can understand why .checkCollisions = true on a heightMap ground... might NOT use a standard mesh.ellipsoid.  FreeCams with .applyGravity would act very strange if an .ellipsoid was used as a heightMap collider.  FreeCams would never fall-to the ground in valleys between mountains.... because the .ellipsoid would span across the valley, mountain to mountain.

Just testing, testing, testing, seeing what I can discover.  Fellow forum helpers... join-in freely with comments and more playground tests.  thx.