Kivy Angle Examples - touch

Question

Angle rotation only works on the first example
I want to understand. Why one example with the angle animation call works and the other fails.
From what I can gather, this has to do with the Builder.load_string.
Working Example
#working example
from kivy.lang import Builder
from kivy.base import runTouchApp
from kivy.uix.image import Image
from kivy.graphics import Rotate
from kivy.properties import NumericProperty
from math import atan2, degrees
from kivy.animation import Animation
Builder.load_string('''
<PlayerImage>:
canvas.before:
PushMatrix
Rotate:
angle: self.angle
axis: (0, 0, 1)
origin: self.center
canvas.after:
PopMatrix
''')
class PlayerImage(Image):
angle = NumericProperty(0)
def on_touch_down(self, touch):
Animation.cancel_all(self)
angle = degrees(atan2(touch.y - self.center_y,
touch.x - self.center_x))
Animation(center=touch.pos, angle=angle).start(self)
root = Builder.load_string('''
Widget:
PlayerImage:
source: 'images/example.png'
allow_stretch: True
keep_ratio: False
''')
runTouchApp(root)
Non Working Example
from kivy.lang import Builder
from kivy.base import runTouchApp
from kivy.uix.image import Image
from kivy.graphics import Rotate
from kivy.properties import NumericProperty
from math import atan2, degrees
from kivy.animation import Animation
class PlayerImage(Image):
angle = NumericProperty(0)
def on_touch_down(self, touch):
Animation.cancel_all(self)
angle = degrees(atan2(touch.y - self.center_y,
touch.x - self.center_x))
Animation(center=touch.pos, angle=angle).start(self)
root = Builder.load_string('''
Widget:
PlayerImage:
source: 'images/example.png'
allow_stretch: True
keep_ratio: False
canvas.before:
PushMatrix
Rotate:
angle: self.angle
axis: (0, 0, 1)
origin: self.center
canvas.after:
PopMatrix
''')
runTouchApp(root)

Answer 1

The second KVlang block is incorrect, there is excess indentation on the Rotate (and, for stylistic purposes, a missing ":" after the PushMatrix).