Kivy – Interactive Applications and Games in Python - Second Edition

Invader – transitions for animations

The previous section uses the default Animation transition. This is a Linear transition, which means that the Widget instance moves from one point to another in a straight line. Invaders trajectories can be more interesting. For example, there could be accelerations, or changes of direction, as shown by the line in the following screenshot:

The following is the code of invader.py:

93. # File name: invader.py 94. from kivy.core.window import Window 95. from kivy.uix.image import Image 96. from kivy.animation import Animation 97. from random import choice, randint 98. from ammo import Missile 99. 100. class Invader(Image): ...