Allow tinting of a tile/object

[Quillraven]

Is your feature request related to a problem? Please describe. I am using Tiled also as an "object editor" for my game. My workflow is:

• Create a tileset with a collection of images
• Add an image to the tileset (e.g. the first frame of the idle animation of a game object like the player)
• Use collision editor to create Box2D fixture definitions
• Assign a class to the tile to add game properties to it, like damage, speed, ...

One of the properties is a color because it is possible to tint a specific game object. From what I know, this is currently not possible. You can set a color for the class, which is not correct in my case because it is a general class for all game objects. You can set a color on an object layer which is also not correct because I need a color for a specific object that is related to a specific tile of a tileset.

Describe the solution you'd like Ideally, we can have a color attribute for a class with a specific key that will be used for tinting and which is then also considered for the tile rendering in Tiled (tile in tileset + object on objectLayer). Maybe "tintColor" as a key or just "tint".

Since you can theoretically have multiple color attributes for a class, Tiled somehow needs to know which color it should use for tinting. That's why a special key might be useful or a separate property type "tint color" that can only be added once to a class.

Describe alternatives you've considered I think there are no alternatives?