Fixed PhysicsSolver, added zoom, linear_damping

src/physics/Hitbox.cpp

@@ -1,4 +1,4 @@
 #include "Hitbox.h"
 
-Hitbox::Hitbox(vec3 position, vec3 halfsize) : position(position), halfsize(halfsize), velocity(0.0f,0.0f,0.0f) {
+Hitbox::Hitbox(vec3 position, vec3 halfsize) : position(position), halfsize(halfsize), velocity(0.0f,0.0f,0.0f), linear_damping(0.1f) {
 }