Precise collision shape using physics

[Ziphold]

Is there a way to set the precise collision shape when using physics. I made a big terrain and when I want to set up a collision shape, (Modify collision shape), I cant add more than 5-6 points. I know it's bad performance wise, but I would like to know if its possible.
Setting precise collision shape in sprite does not work.

In advance-thank you.

 

[Jezla]

Physics objects do not use the sprite for collision checking, they use fixtures. Fixtures are limited to 8 points (iirc), and cannot be convex. You can, however, bind more than one fixture to an object to make more complex shapes. If you're new to using physics, I'd really recommend going through the physics tutorials that come with GM:S.