A primitive scene graph

[Avokadoen]

This is a bigger task that requires:

• [x] instancing
• [x] able to draw multiple geometric shape types
• [ ] a geometric shape registry
• [ ] a transform abstraction
• [ ] preferably a component trait which our transform abstraction can be part of
• [ ] the scene graph

[Avokadoen]

Instancing was complete in de1e8d468b8ce8434042234d3618573b8b81c3c6