我看了下英文文档：

public bool convex;

Description

Use a convex collider from the mesh.

This means that if you have this set to true, your mesh collider wont have holes or entrances. Convex meshes can collide with other convex colliders and non-convex meshes. Thus convex mesh colliders are suitable on rigidibodies, if you really need more detailed colliders than what the primitive colliders provide you with.

这个意思是 设置了convex就不会是那种mesh状态(交叉的)的collider,而是一整块一整块的collider 但是我设置了之后为什么连Collider的大小都变了？

本来plane就是一个面片，他的碰撞器也是一个面片，加上conves，就是一个封闭的

就像原来只是一个布，现在封闭之后变成了一个长方形的