# Sometimes can't use the rendered mesh as a collider in Unity?

Most of the times I can use the Mesh Filter's mesh as collider in Mesh Collider

But sometimes there is just nothing. No collider. Why?

I used this free asset: https://assetstore.unity.com/packages/3d/environments/fantasy/green-forest-22762

• What do you mean "There is just nothing. No collider." ? What if you add a mesh collider yourself ? Jan 25, 2019 at 10:05
• Does the tree have a rigidbody component further down? Mesh colliders with rigidbodies must be convex in order to work. Jan 25, 2019 at 22:40