Dealing with collisions

With so many bullets flying around and having the Enemy objects to check collisions against, it is important that there be a separate class that does this collision checking for us. This way we know where to look if we decide we want to implement a new way of checking for collisions or optimize the current code. The Collision.h file contains a static method that checks for collisions between two SDL_Rect objects:

const static int s_buffer = 4;

static bool RectRect(SDL_Rect* A, SDL_Rect* B)
{
  int aHBuf = A->h / s_buffer;
  int aWBuf = A->w / s_buffer;

  int bHBuf = B->h / s_buffer;
  int bWBuf = B->w / s_buffer;

  // if the bottom of A is less than the top of B - no collision
  if((A->y + A->h) - aHBuf <= B->y + bHBuf)  { return false; }

  // if the top of A is more than the bottom of B = no collision
  if(A->y + aHBuf >= (B->y + B->h) - bHBuf)  { return false; }

  // if the right of A is less than the left of B - no collision...