class Artist:
"Abstract base class for someone who renders into a Figure"
def __init__(self):
self._drawingArea = None
self._drawable = None
def clip_gc(self, gc):
"The gc clipping function; no clip by default"
pass
def get_child_artists(self):
'Return all artists contained in self'
return []
def get_window_extent(self):
"""
Return the bounding box as left, bottom, width, height in
window coords
"""
l, b, w, h = self.get_data_extent()
w, h = self.transform_scale_to_win(w, h)
l, b = self.transform_points_to_win(l, b)
return l, b, w, h
def get_data_extent(self):
"""
Return the bounding box as left, bottom, width, height in
data coords of the area
"""
raise NotImplementedError, "Derived must override"
def transform_points_to_win(self, x, y):
"Transform the points x, y to window coords. Default is do nothing"
return x, y
def transform_scale_to_win(self, xscale, yscale):
"Transform the xscale, yscale to window coords. Default is do nothing"
return xscale, yscale
def draw(self, drawable=None, *args, **kwargs):
'Derived classes drawing method'
if drawable is None: drawable = self._drawable
if drawable is None: return
self._draw(drawable, *args, **kwargs)
def _draw(self, drawable, *args, **kwargs):
'Derived classes drawing method'
raise NotImplementedError, 'Derived must override'
def set_drawing_area(self, da):
'Set the drawing area that you render into'
self._drawingArea = da
self._drawable = da.window
for artist in self.get_child_artists():
artist.set_drawing_area(da)
def wash_brushes(self):
'Erase any state vars that would impair a draw to a clean palette'
for artist in self.get_child_artists():
artist.wash_brushes()
