Add functionality to tilemap that automatically sets precise colisions in the shape of the tile.

[RakibRyan]

Describe the project you are working on

a tilemap based game where a lot of tiles aren't square.

Describe the problem or limitation you are having in your project

When working with non square tiles manual collision shape setup becomes tedious.

Describe the feature / enhancement and how it helps to overcome the problem or limitation

add a button in tilemap that when pressed the physics layer in tile autosets to shape of the tile.

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

it could be like unity's auto colission shape.

If this enhancement will not be used often, can it be worked around with a few lines of script?

the enhancement will be used often if people had access to it.

Is there a reason why this should be core and not an add-on in the asset library?

it's too small to be it's own asset and too tedious to not be in core engine.

[AThousandShips]

Please explain some more details on what this would mean. Would it detect non-transparent pixels? Should it be strictly convex or concave as well? How would yo activate this? People aren't guaranteed to have used unity or this specific feature so please explain it instead

[AThousandShips]

So to clarify, it would be based on the outline of the visible parts, i.e. with a transparent background? It wouldn't, for example, work with a red shape on a white background

[AThousandShips]

I didn't import anything :) I'm just asking again because it was one of my questions above that was intended to clarify what you were asking for since you gave so little detail

[aXu-AP]

It could be doable since there's already a similiar functionality for Sprite2D (accessible by selecting a Sprite2D and selecting from toolbar Sprite2D -> Create CollisionPolygon2D Sibling).
I think it would be placed in this menu here (something like "generate polygons from transparency"):

Altough the option should propably be compatible with tile selection as well, since the user might not want to generate collision for all tiles.

This would open a dialog with following options:

• Select physics layer
• Select navigation layer (creates inverted polygon)
• Select occlusion layer
• Same options as in sprite->polygon tool (simplification, shrink, grow)

However, I think there could be a potential problem in how to handle slopes. Take this for example:

How the algorithm should determine where to put this point to prevent this step? For tile corners a special parameter ("snap to corners distance") could be provided, but for this kind of middle points its harder. One possibility is to ensure connectivity between adjacent tiles, but this would add a special requirement for how the tiles are arranged in the texture. Any ideas how to overcome this problem?

[aXu-AP]

I wonder what kind of tileset would have so exotic shapes? I mean, what I suggested would work even with such shapes. I just gave the most common example where this would be used, slopes, and what problems could arise.

[AThousandShips]

This would be very much dependent on what the user is wanting for these kinds of strange shapes, would they want a convex hull, or just a partial hull without too much detail, etc.

Though I don't think it's representative of almost any use case of this feature