Method find_intersection

pygorithm/geometry/line2.py:401–599

Find the intersection between the two lines. The lines may optionally be offset by a fixed amount. This will incur a minor performance penalty which is less than that of recreating new lines. Two lines are considered touching if they only

(line1, line2, offset1 = None, offset2 = None)

    
    @staticmethod
    def find_intersection(line1, line2, offset1 = None, offset2 = None):
        """
        Find the intersection between the two lines.
        
        The lines may optionally be offset by a fixed amount. This 
        will incur a minor performance penalty which is less than 
        that of recreating new lines.
        
        Two lines are considered touching if they only share exactly
        one point and that point is an edge of one of the lines. 
        
        If two lines are parallel, their intersection could be a line.
        
        .. tip::
        
            This will never return True, True
        
        :param line1: the first line
        :type line1: :class:`pygorithm.geometry.line2.Line2`
        :param line2: the second line
        :type line2: :class:`pygorithm.geometry.line2.Line2`
        :param offset1: the offset of line 1
        :type offset1: :class:`pygorithm.geometry.vector2.Vector2` or None
        :param offset2: the offset of line 2
        :type offset2: :class:`pygorithm.geometry.vector2.Vector2` or None
        :returns: (touching, overlapping, intersection_location)
        :rtype: (bool, bool, :class:`pygorithm.geometry.line2.Line2` or :class:`pygorithm.geometry.vector2.Vector2` or None)
        """
        
        
        # We will ensure that: 
        #  - If one line is vertical and one horizontal, line1 is the vertical line
        #  - If only one line is vertical, line1 is the vertical line
        #  - If only one line is horizontal, line1 is the horizontal line
        
        if line2.vertical and not line1.vertical:
            return Line2.find_intersection(line2, line1, offset2, offset1)
        if line2.horizontal and not line1.horizontal and not line1.vertical:
            return Line2.find_intersection(line2, line1, offset2, offset1)
            
        l1_st_x = line1.start.x + (offset1.x if offset1 is not None else 0)
        l1_st_y = line1.start.y + (offset1.y if offset1 is not None else 0)
        l1_en_x = line1.end.x + (offset1.x if offset1 is not None else 0)
        l1_en_y = line1.end.y + (offset1.y if offset1 is not None else 0)
        
        l2_st_x = line2.start.x + (offset2.x if offset2 is not None else 0)
        l2_st_y = line2.start.y + (offset2.y if offset2 is not None else 0)
        l2_en_x = line2.end.x + (offset2.x if offset2 is not None else 0)
        l2_en_y = line2.end.y + (offset2.y if offset2 is not None else 0)
        
        if line1.vertical and line2.vertical:
            # Two vertical lines
            if not math.isclose(l1_st_x, l2_st_x):
                return False, False, None
            
            aal1 = axisall.AxisAlignedLine(None, l1_st_y, l1_en_y)
            aal2 = axisall.AxisAlignedLine(None, l2_st_y, l2_en_y)