c# - Unity3D Changing Ball Direction When Hitting a Cube -

i'm working on simple paddle game project nowadays. in begining, everything's looking good. but, when complete level design , publish game, see gameobjects in scene moving slow. think, pass on unity3d's physics limit. if try math instead of unity3d's colider, can finish first project. (i tried use separating axis theorem, can't handle x , y coordinates on unity3d.)

i need help. lot time. (and if can handle problem, share project on internet, beginner people me.)

in project, achieved simulation using boxcolider, because of unity3d physics limit, don't want use colider in project.

you can't not detect collision. i'd recommend using unity's colliders that, since they're not bad. first thing notice in first simulation, have 4 box colliders, when instead should have one. use oncollisionenter event (on spheres) reflect them off box.