scenic

#
#  Created by Boyd Multerer on 2018-07-23.
#  Copyright © 2018 Kry10 Industries. All rights reserved.
#
# Seperate Context out into its own file

defmodule Scenic.ViewPort.Context do
  @moduledoc false

  alias Scenic.Math
  alias Scenic.Graph
  alias Scenic.ViewPort.Input
  alias Scenic.ViewPort.Context

  # note: would like to define tx: and inverse_tx: as Matrix.identity() directly
  # as defaults in the struct. However, this breaks when cross-compiling to
  # opposite endian devices under Nerves. So call Context.build() when you want
  # to create a new Context, or fill in the matrices with a runtime call
  # to Matrix.identity yourself.

  # @identity   Matrix.identity

  defstruct viewport: nil,
            graph_key: nil,
            tx: nil,
            inverse_tx: nil,
            uid: nil,
            id: nil,
            raw_input: nil

  @type t :: %Context{
          viewport: GenServer.server(),
          graph_key: Graph.key(),
          tx: Math.matrix(),
          inverse_tx: Math.matrix(),
          raw_input: Input.t(),
          uid: pos_integer,
          id: any
        }

  @spec build(map) :: Context.t()
  def build(%{} = params) do
    Map.merge(
      %Context{tx: Math.Matrix.identity(), inverse_tx: Math.Matrix.identity()},
      params
    )
  end
end