Animation

Summary

tranimate is based on a fairly general framework implemented by Animate.py for 2D or 3D animation.

Instead of conventional matplotlib plotting

ax.plot(1,2)

we do this

anim = Animate(ax)
anim.plot(1,2)

which adds a line plot to the display list.

Internals

The Animate object mimics the behaviour of an Axis3D or Axis object and supports methods:

matplotlib primitive	display list object
plot()	_Line
text()	_Text
quiver()	_Quiver

The object is drawn to the axes using the equivalent matplotlib commands, but the parameters and a handle to the Artist are kept in an object in the display list.

The display list has a __repr__ method which shows the display list content.

Rendering

The A._draw(T) transforms the parameters of every item in the display list and renders them to the canvas. It does this by invoking the draw(T) method for every item in the display list.

This assumes that all objects are drawn as if they were at the identity pose.

Animation

The run() method uses matplotlib animation machinery, FuncAnimation, to which provides an event handler to step the animation. That handler gets the next transform and uses _draw(T) to display the object.

Future work

• Multiple independently moving objects could be handled by separate display lists, but the event handler would need to be update to allow this.

• Extend the supported primitives to include points (scatter) and patches.