Bug in scene.pick ?

[Temechon]

Hello, 

 

I'm currently using a lot of picking actions, as described in this playground : http://www.babylonjs.com/playground/#1HCGBN

 

This scene is a simple ground in a biiiiig red sphere (a skydome).

A click on the ground creates a box. Try to click on the sphere in front of you : no box.

Well, there is a box... Press the 'back' arrow key of your keyboard. Surprise !

...

What ?The box is behind me ? What the hell ... ?

 

I came to the conclusion there was a bug in the function scene.pick, so I tried to investigate...

And here is what I found : 

Ray.prototype.intersectsTriangle = function (vertex0, vertex1, vertex2) {    ...    var det = Vector3.Dot(this._edge1, this._pvec);    if (det === 0) {        return null;    }    ...}

In my case, the box is behind the camera because the dot product is negative. I think (but I'm not sure as I'm not a math professional :/ ) that it should never be negative in a picking case...

So I added this : 

if (det <= 0 ) {    return null;}

And it works... But I don't have any box on my ground now :/ 

 

Help me Babylon lovers ! What should I do ?

 

Cheers, 

[GameMonetize]

Your problem is that dot < 0 will break the general case

You should set sphere.isPickable = false

[Temechon]

Yes, but the sphere cannot be targeted anymore :/

 

Actually I want to pick always in front of the camera, not behind it. How can something like this be achieved ? In my mind, it can be if the cos between my two vectors is > 0, thus the dot product > 0... But I don't understand why it does not work with the ground

[GameMonetize]

try with dot >= 0

[GameMonetize]

But btw the problem is that you are INSIDE the sphere with normals pointing outside 

[Temechon]

Ooookkk I think I got it... Thanks Delta

I will try to find a workaround for it.