Function intrSphereVsSphere
Checks two spheres for intersection
Example
Sphere sphere1 = Sphere(Vector3f(0, 0, 0), 1.0f);
Sphere sphere2 = Sphere(Vector3f(1.9f, 0, 0), 1.0f);
Intersection isec = intrSphereVsSphere(sphere1, sphere2);
assert(isec .fact);
assert(isConsiderZero(isec .penetrationDepth - 0.1f));
assert(isAlmostZero(isec .point - Vector3f(0.9f, 0.0f, 0.0f)));
assert(isAlmostZero(isec .normal - Vector3f(-1.0f, 0.0f, 0.0f)));