+ """

+ A graphical connection for ports.

+ The connection has 2 parts, the arrow and the wire.

+ The coloring of the arrow and wire exposes the status of 3 states:

+ enabled/disabled, valid/invalid, highlighted/non-highlighted.

+ The wire coloring exposes the enabled and highlighted states.

+ The arrow coloring exposes the enabled and valid states.

+ """

+ def __init__(self): Element.__init__(self)

+ def get_coordinate(self):

+ """

+ Get the 0,0 coordinate.

+ Coordinates are irrelevant in connection.

+

+ Returns:

+ 0, 0

+ """

+ return (0, 0)

+ def get_rotation(self):

+ """

+ Get the 0 degree rotation.

+ Rotations are irrelevant in connection.

+

+ Returns:

+ 0

+ """

+ return 0

+ def create_shapes(self):

+ """Precalculate relative coordinates."""

+ Element.create_shapes(self)

+ self._sink_rot = None

+ self._source_rot = None

+ self._sink_coor = None

+ self._source_coor = None

+ #get the source coordinate

+ try:

+ connector_length = self.get_source().get_connector_length()

+ except:

+ return

+ self.x1, self.y1 = Utils.get_rotated_coordinate((connector_length, 0), self.get_source().get_rotation())

+ #get the sink coordinate

+ connector_length = self.get_sink().get_connector_length() + CONNECTOR_ARROW_HEIGHT

+ self.x2, self.y2 = Utils.get_rotated_coordinate((-connector_length, 0), self.get_sink().get_rotation())

+ #build the arrow

+ self.arrow = [(0, 0),

+ Utils.get_rotated_coordinate((-CONNECTOR_ARROW_HEIGHT, -CONNECTOR_ARROW_BASE/2), self.get_sink().get_rotation()),

+ Utils.get_rotated_coordinate((-CONNECTOR_ARROW_HEIGHT, CONNECTOR_ARROW_BASE/2), self.get_sink().get_rotation()),

+ ]

+ self._update_after_move()

+ if not self.get_enabled(): self._arrow_color = Colors.CONNECTION_DISABLED_COLOR

+ elif not self.is_valid(): self._arrow_color = Colors.CONNECTION_ERROR_COLOR

+ else: self._arrow_color = Colors.CONNECTION_ENABLED_COLOR

+ def _update_after_move(self):

+ """Calculate coordinates."""

+ self.clear() #FIXME do i want this here?

+ #source connector

+ source = self.get_source()

+ X, Y = source.get_connector_coordinate()

+ x1, y1 = self.x1 + X, self.y1 + Y

+ self.add_line((x1, y1), (X, Y))

+ #sink connector

+ sink = self.get_sink()

+ X, Y = sink.get_connector_coordinate()

+ x2, y2 = self.x2 + X, self.y2 + Y

+ self.add_line((x2, y2), (X, Y))

+ #adjust arrow

+ self._arrow = [(x+X, y+Y) for x,y in self.arrow]

+ #add the horizontal and vertical lines in this connection

+ if abs(source.get_connector_direction() - sink.get_connector_direction()) == 180:

+ #2 possible point sets to create a 3-line connector

+ mid_x, mid_y = (x1 + x2)/2.0, (y1 + y2)/2.0

+ points = [((mid_x, y1), (mid_x, y2)), ((x1, mid_y), (x2, mid_y))]

+ #source connector -> points[0][0] should be in the direction of source (if possible)

+ if Utils.get_angle_from_coordinates((x1, y1), points[0][0]) != source.get_connector_direction(): points.reverse()

+ #points[0][0] -> sink connector should not be in the direction of sink

+ if Utils.get_angle_from_coordinates(points[0][0], (x2, y2)) == sink.get_connector_direction(): points.reverse()

+ #points[0][0] -> source connector should not be in the direction of source

+ if Utils.get_angle_from_coordinates(points[0][0], (x1, y1)) == source.get_connector_direction(): points.reverse()

+ #create 3-line connector

+ p1, p2 = map(int, points[0][0]), map(int, points[0][1])

+ self.add_line((x1, y1), p1)

+ self.add_line(p1, p2)

+ self.add_line((x2, y2), p2)

+ else:

+ #2 possible points to create a right-angled connector

+ points = [(x1, y2), (x2, y1)]

+ #source connector -> points[0] should be in the direction of source (if possible)

+ if Utils.get_angle_from_coordinates((x1, y1), points[0]) != source.get_connector_direction(): points.reverse()

+ #points[0] -> sink connector should not be in the direction of sink

+ if Utils.get_angle_from_coordinates(points[0], (x2, y2)) == sink.get_connector_direction(): points.reverse()

+ #points[0] -> source connector should not be in the direction of source

+ if Utils.get_angle_from_coordinates(points[0], (x1, y1)) == source.get_connector_direction(): points.reverse()

+ #create right-angled connector

+ self.add_line((x1, y1), points[0])

+ self.add_line((x2, y2), points[0])

+ def draw(self, gc, window):

+ """

+ Draw the connection.

+

+ Args:

+ gc: the graphics context

+ window: the gtk window to draw on

+ """

+ sink = self.get_sink()

+ source = self.get_source()

+ #check for changes

+ if self._sink_rot != sink.get_rotation() or self._source_rot != source.get_rotation(): self.create_shapes()

+ elif self._sink_coor != sink.get_coordinate() or self._source_coor != source.get_coordinate():

+ try:

+ self._update_after_move()

+ except:

+ return

+ #cache values

+ self._sink_rot = sink.get_rotation()

+ self._source_rot = source.get_rotation()

+ self._sink_coor = sink.get_coordinate()

+ self._source_coor = source.get_coordinate()

+ #draw

+ if self.is_highlighted(): border_color = Colors.HIGHLIGHT_COLOR

+ elif self.get_enabled(): border_color = Colors.CONNECTION_ENABLED_COLOR

+ else: border_color = Colors.CONNECTION_DISABLED_COLOR

+ Element.draw(self, gc, window, bg_color=None, border_color=border_color)

+ #draw arrow on sink port

+ try:

+ gc.set_foreground(self._arrow_color)

+ window.draw_polygon(gc, True, self._arrow)

+ except:

+ return