def __init__(self, brushinfo=None, painting_only=False):
"""Initialize
:param brushinfo: the lib.brush.BrushInfo instance to use
:param painting_only: only use painting layers
If painting_only is true, then no tempdir will be created by the
document when it is initialized or cleared.
"""
object.__init__(self)
if not brushinfo:
brushinfo = brush.BrushInfo()
brushinfo.load_defaults()
self._layers = layer.RootLayerStack(self)
self._layers.layer_content_changed += self._canvas_modified_cb
self.brush = brush.Brush(brushinfo)
self.brush.brushinfo.observers.append(self.brushsettings_changed_cb)
self.stroke = None
self.command_stack = command.CommandStack()
self._painting_only = painting_only
self._tempdir = None
# Optional page area and resolution information
self._frame = [0, 0, 0, 0]
self._frame_enabled = False
self._xres = None
self._yres = None
# Backgrounds for rendering
blank_arr = numpy.zeros((N, N, 4), dtype='uint16')
self._blank_bg_surface = tiledsurface.Background(blank_arr)
self.clear()
def clear(self, init=False):
self.split_stroke()
if not init:
bbox = self.get_bbox()
# throw everything away, including undo stack
self.command_stack = command.CommandStack()
self.command_stack.stack_observers = self.command_stack_observers
self.set_background((255, 255, 255))
self.layers = []
self.layer_idx = None
self.add_layer(0)
# disallow undo of the first layer
self.command_stack.clear()
self.unsaved_painting_time = 0.0
if not init:
for f in self.canvas_observers:
f(*bbox)
self.call_doc_observers()