Trouble tracking down a "convex decomposition" error

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:bust_in_silhouette: Asked By alwaysusa

Hey all!

I’m getting a single error when I run my game (not a game breaker, but a red error) and I can’t figure out how to track down the problem.

The error states:
decompose_polygon_in_convex: Convex decomposing failed!
<C++ Source> core/math/geometry.cpp:702 @ decompose_polygon_in_convex()

I’m guessing it’s a tilemap collision error, but as I have multiple tilemaps and tons of unique tiles within those tilemaps, I’m trying to figure which tile or collision volume within those tiles is causing the error.

Does anyone know of a way to “drill down” further into the error? I had a quick look at profiler but don’t see any options there to help me isolate the error.

Thanks in advance!

I’m guessing what’s happening is that, when the engine computes the collisions, it tries to use a convex algorithm for some polygons. When it gets to certain polygons in your tilemap collisions, it can’t apply that algorithm, and gives an error. My only suggestion is to find polygons in the tilemap whose outer angles are greater than 180° (i.e. convex polygons) and change the points of the collision outline.

Ertain | 2020-04-08 02:51

Thank you for the info. I guess I’ll have to go through each tileset one by one to try and figure out which ones may be causing the issue. I was hoping there was a way to get more info on the error, but if not I guess it’s time for a little elbow grease.


alwaysusa | 2020-04-08 05:06

I have the same problem, and i managed to track down a tile where it doesn’t highlight blue when selected in the tileset window, the problem is I can’t remove the tile without starting over. Any tips how to fix?

goodymind | 2022-05-16 07:21