game
	basically handles the game logic and delegates audio/video to respective management tools

	track current state and updates state
	calls renderers to draw the scene to framebuffer(s)
	calls a mixer to play audio for a scene

	key functions:
	render()
	update()

	holds any scenes required for gameplay
	holds window for game to be drawn in


scene
	basically a central repository for raw data in a scene

	holds cameras that exist in a given scene
	holds objects that exist in a given scene
	holds textures that exists for a given scene
	holds audio that exists for a given scene

renderer
	basically takes a scene and draws it a specific way to a framebuffer

	key functions:
	set_vpmatrix(mat4&)
		set up view-projection matrix for use in rendering
	render(scene&)
		draw the given scene the this renderer's framebuffer


vertex
	basically describes a vertex
	holds position
	holds texture coordinates
	holds vertex color
	holds normals

mesh
	basically holds vertex data for a given shape
	holds an array of vertices that describe a shape to draw

	key functions:
	render(shader&)
		draw this mesh onto the currently bound framebuffer using the given shader

model
	basically handles a collection of meshes that constitute a single entity
	hold an array of meshes that describe the composition of a complex model

	key functions:
	render(shader&)
		draw this model onto the currently bound framebuffer using the given shader

instance
	basically holds handles to a mesh/model/any other needed data for use by multiple objects

renderable
	basically any type with a render(shader_program&) function
	hold an instance object reffing to a model
	hold a model matrix

square
	is a renderable that specifically references a square model