title: rotate only the image not the matrix
body: <p>I want to load an image, rotate (because the image is vertical) and code after independent of the rotation (continuously moving right) </p>
  
  <p>I can rotate an image and continue coding, but after that the image will have an unexpected behaviour (it start to move upward instead of right)</p>
  
  <pre><code>from kivy.app import App
  from kivy.uix.widget import Widget
  from kivy.graphics import Rectangle, Rotate, Color
  from kivy.clock import Clock
  from kivy.graphics import PushMatrix, PopMatrix
  
  
  
  class Trunk(Widget):
      def __init__(self, **kwargs):
          super().__init__(**kwargs)
          print(self.size, self.center)
          self.pos = 500, 500
          self.size = 200, 100
          with self.canvas.before:
              PushMatrix()
              Rotate(angle=90, axis=(0, 0, 1), origin=self.center)
              self.rect = Rectangle(pos=self.pos, size=self.size)
              self.bind(pos=self.update_rect)
  
          with self.canvas.after:
              PopMatrix()
  
      def update_rect(self, *args):
          self.rect.pos = self.pos 
  
  
  class Game(Widget):
      pass
  
      def update(self, dt):
          self.children[0].x += .5
  
  class TestApp(App):
      def build(self):
          game = Game()
          trunk = Trunk()
  
          game.add_widget(trunk)
          Clock.schedule_interval(game.update, 1.0 / 60)
  
          return game
  
  TestApp().run()
  </code></pre>
  
  <p>I expect that the rectangle go right (self.children[0].x += .5) because I'm increasing the x, </p>
  
  <p>Thank you</p>