Type: function(object, extraConfig)
A function that should return true if an object is visible, and false otherwise. When an object is invisible, it can't be selected or interacted with. Can be based on
object.category, or on other criteria.
The object types that can be made invisible are: "seat", "table", "booth", "generalAdmission" and "section".
By default, all objects are visible.
The parameters that are passed to isObjectVisible are:
- object: the current object
- extraConfig: see extraConfig
this function is called for each object on the chart; make sure it's fast, or chart rendering times will suffer. Avoid using slow methods such as Array.indexOf. Read more here.