def set_scale(self, ctx, page_w, page_h):
"""
Automatically sets a scale factor for the drawing.
This will normally be called after the set_scale()
function of a subclass has set the scale factor.
'page_h' and 'page_w' should already have been up-scaled
by the time this happens.
Arguments:
ctx -- a Pycairo context
page_w, page_h -- height and width of the drawing area
"""
# Upscale lines
# Note that self.dim_line_length is used to calculate
# the lengths of radius dimension lines. These lengths
# can differ for individual subclasses, and so
# self.dim_line_length should be set in the subclass's
# own set_scale() function, but the dimension is common
# to all Pipe subclasses, and so we upscale it here.
self.dim_line_length /= self.scale # pylint: disable=E1101
# Call parent function
DrawnComponent.set_scale(self, ctx, page_w, page_h)
