hi i start write some documentation here for custom material ( its realy easy for me to make it here but i can move it in documentation after that complete ) definition : Custom Material inherited from stable version of Standard material (a carbon Copy of BABYLON.StandarMaterial) when we need CustomMaterial ? : any time you wanna make any custom option but you can't manage that in standard material .  vertex shader definitions :  position(readonly)  or positionUpdated(vec3)