def _compute_size_from_constraint(self):
        """ Computes the actual size in pixels from the targets size constraint """
        w, h = Globals.resolution.x, Globals.resolution.y
        self._size = LVecBase2i(self._size_constraint)
        if self._size_constraint.x < 0:
            self._size.x = (w - self._size_constraint.x - 1) // (-self._size_constraint.x)
        if self._size_constraint.y < 0:
            self._size.y = (h - self._size_constraint.y - 1) // (-self._size_constraint.y)
 Computes the actual size in pixels from the targets size constraint 
metadrive/render_pipeline/rpcore/render_target.py