Group objects, Substract "half" collider?

News & General Discussion
1

I’m wondering and didn’t found any option to:

  1. Kinda glue objects, but keeping all options, behaviours…

  2. Substract 1 cube from another like I could do in 3D progs

  3. Kinda half collider, that is not going around an object. Please don’t tell me to reduce the size and move position. Question is definately about kinda cutting a collider box.

I try some “viewing angle” of enemy. Means when I don’t get into viewing angle, Enemy can’t see n react on me.

2

Your approach is wrong. Game engines does not function on the same manner as 3D applications. The best advice i can give you is to look for the official projects and for tutorials like BurgZergArcade videos. After that if you still dont understand some things, at least you will be able to expose your problems in a more clear way.

3

You can’t cut a collider box.

4

I definately know the difference between 3D Game Engine for many years. That doesn’t mean unity with all it’s power would not be able to substract objects each other. :wink:

hippo: ty

5

You can’t do a Boolean on Colliders.

Colliders are not meshes (unless of course it’s the type Mesh Collider). They are just geometrical constructs. In Max, or Maya a GeoSphere is a set of dozens to hundreds of triangles, and is not actually spherical. In Unity a Sphere collider is a position and radius and is perfectly spherical.

To determine collisions between two GeoSpheres you would have to compare all points with opposing normals and compare them against the normals of the opposing surface, this could be anywhere from 10-1000s of mathematical computations.
To determine collisions between Spheres it does a distance calculation you take the distance between the two spheres and see if it is less than the two radii combined. This is 1 mathematical computation, and savings by a factor of 10x or greater compared to colliding GeoSpheres.

If you were to cut a chunk out of this sphere you would no longer be able to do simple physics computations and you would drag the entire physics engine to it’s knees (as you now have to triangulate the entire Sphere and then compare vert per vert against other colliders) with a few simple boolean operations. While mathematically it could be accomplished it is such a bad idea to perform those sorts of operations that it is not available in any 3D physics system that I know of.