gravity-controlled-rotation-test.py

gravity-controlled-rotation-test.py

# Demo code showing how to use iPad gravity sensor to control cannon orientation
# cannon clipart downloaded from 
# http://www.clker.com/cliparts/7/9/9/b/1206570465701485742johnny_automatic_cannon_3.svg.med.png
from scene import *
from random import random
import math

class MyScene (Scene):
  
  def setup(self):
    # This will be called before the first frame is drawn.
    # Set up the root layer and one other layer:
    self.root_layer = Layer(self.bounds)
    bottom_center = Point(self.bounds.w/2, 0)
    self.layer = Layer(Rect(bottom_center.x - 64, bottom_center.y, 128, 128))
    self.layer.image = '_cannon'
    self.root_layer.add_layer(self.layer)
    self.angle = 90

  def draw(self):
    # Update and draw our root layer. For a layer-based scene, this
    # is usually all you have to do in the draw method.
    background(0.00, 1.00, 1.00)
    g = gravity()
    gravity_angle = math.degrees(math.atan2(g.y, g.x))
    if -180 <= gravity_angle <= 0:
      self.angle = math.degrees(math.atan2(g.y, g.x)) + 180
      
    self.layer.animate('rotation', self.angle, 1/60)
    self.root_layer.update(self.dt)
    self.root_layer.draw()
  
  def touch_began(self, touch):
    pass
  
  def touch_moved(self, touch):
    pass
  
  def touch_ended(self, touch):
    pass

run(MyScene())