class TurtleWidget(CanvasWidget):
def newTKWidget(self, parent, hOptions):
return super().newTKWidget(parent, hOptions)
def initialize(self, hOptions):
self.screen = TurtleScreen(self.tkWidget)
self.tkTurtle = RawTurtle(self.screen)
self.screen.mode('world')
self.tkTurtle.setheading(90)
if 'speed' in hOptions:
self.curSpeed = int(hOptions['speed'])
else:
self.curSpeed = 1
self.lSaveStack = [] # stack to save/restore state on
def setBounds(self, xmin, ymin, xmax, ymax, padding=15):
width = xmax - xmin
height = ymax - ymin
if (width > height):
halfdiff = (width - height) / 2
ymin -= halfdiff
ymax += halfdiff
else:
halfdiff = (height - width) / 2
xmin -= halfdiff
xmax += halfdiff
self.screen.setworldcoordinates(
xmin - padding,
ymin - padding,
xmax + padding,
ymax + padding,
)
def reset(self):
self.screen.reset()
def move(self, n):
tkTurtle = self.tkTurtle
assert isinstance(tkTurtle, RawTurtle)
tkTurtle.speed(self.curSpeed)
tkTurtle.forward(n)
def turn(self, d):
tkTurtle = self.tkTurtle
assert isinstance(tkTurtle, RawTurtle)
tkTurtle.speed(self.curSpeed)
tkTurtle.right(d)
# --- Turtle state includes these fields:
# xpos, ypos, heading, isvisible, isdown
def saveState(self):
tkTurtle = self.tkTurtle
assert isinstance(tkTurtle, RawTurtle)
self.lSaveStack.append([
tkTurtle.xcor(),
tkTurtle.ycor(),
tkTurtle.heading(),
tkTurtle.isvisible(),
tkTurtle.isdown(),
])
def restoreState(self):
tkTurtle = self.tkTurtle
assert isinstance(tkTurtle, RawTurtle)
if len(self.lSaveStack) == 0:
raise Exception("restoreState(): No saved state to restore")
lState = self.lSaveStack.pop()
saved_x = lState[0]
saved_y = lState[1]
cur_x = tkTurtle.xcor()
cur_y = tkTurtle.ycor()
# --- determine whether we need to hide the turtle
if tkTurtle.isvisible():
dist = hypot(saved_x - cur_x, saved_y - cur_y)
mustHide = (dist > 1)
else:
mustHide = False
if mustHide:
tkTurtle.hideturtle()
tkTurtle.penup()
tkTurtle.setposition(saved_x, saved_y)
tkTurtle.setheading(lState[2])
if lState[3] and mustHide:
tkTurtle.showturtle()
if lState[4]:
tkTurtle.pendown()
def moveTo(self, x, y):
tkTurtle = self.tkTurtle
tkTurtle.penup()
tkTurtle.hideturtle()
tkTurtle.setposition(x, y)
tkTurtle.setheading(90)
tkTurtle.pendown()
tkTurtle.showturtle()
def drawAt(self, x, y, func):
# --- Must not draw or show movement
tkTurtle = self.tkTurtle
self.saveState()
self.moveTo(x, y)
func(self)
self.restoreState()
