# Visible 3D entity in the game world
#
# Similar to `gamnit::Sprite` which is in 2D.
#
# Each actor associates a `model` to the position `center`.
# The appearance is modified by `rotation`, `scale` and `alpha`,
# as well as the attributes of `model` itself.
#
# ~~~
# import gamnit::depth
#
# # Load model from the assets folder
# var model = new Model("path/in/assets.obj")
#
# # Create and configure an actor
# var actor = new Actor(model, new Point3d[Float](0.0, 0.0, 0.0))
# actor.scale = 2.0
#
# # Add to the visible game world
# app.actors.add actor
# ~~~
class Actor

	# Model used to draw this actor
	var model: Model

	# Position of this sprite in world coordinates
	var center: Point3d[Float] is writable

	# Rotation around the X axis (+ looks up, - looks down)
	#
	# Positive values look up, and negative look down.
	#
	# All actor rotations follow the right hand rule.
	# The default orientation of the model should look towards -Z.
	var pitch = 0.0 is writable

	# Rotation around the Y axis (+ turns left, - turns right)
	#
	# Positive values turn `self` to the left, and negative values to the right.
	#
	# All actor rotations follow the right hand rule.
	# The default orientation of the model should look towards -Z.
	var yaw = 0.0 is writable

	# Rotation around the Z axis (looking to -Z: + turns counterclockwise, - clockwise)
	#
	# From the default camera point of view, looking down on the Z axis,
	# positive values turn `self` counterclockwise, and negative values clockwise.
	#
	# All actor rotations follow the right hand rule.
	# The default orientation of the model should look towards -Z.
	var roll = 0.0 is writable

	# Scale applied to the model
	var scale = 1.0 is writable

	# Transparency applied to the model on draw
	#
	# This value may be ignored by some materials.
	# Non-opaque values may result in artifacts as there is no specialized
	# support for transparent models and the depth buffer.
	var alpha = 1.0 is writable
end