PointLight.parent

Hi everyone,

There was an update in computeTransformedPosition in PointLight.js for how the position of the light is derived. It transforms an already transformed vector causing continuous transformations thereafter. I have used someone's playground demo   to display the behavior.

http://www.babylonjs-playground.com/#24O839#11

http://www.babylonjs-playground.com/#NTL8V#31

Another Question. If I were to make changes and make a pull request, if I ever will, Would it be right to make those changes in the .ts and .js files in the src folder.

Thanks