lib/scenic/primitive/transform/matrix.ex

#
#  Created by Boyd Multerer on 2017-10-02.
#  Copyright © 2017 Kry10 Limited. All rights reserved.
#

defmodule Scenic.Primitive.Transform.Matrix do
  @moduledoc """
  Apply an arbitrary matrix.

  Applies an arbitrary 4x4 matrix to a primitive. For now, only the 2-D part
  of the matrix actually does anything. Am using 4x4 though for future compatibility.

  Example:

  ```elixir
  @matrix [ 0, 1, 2, 3,
            4, 5, 6, 7,
            8, 9, 10, 11,
            12, 13, 14, 15 ]
    |> Scenic.Math.Matrix.Matrix.Utils.to_binary()

  graph
    |> text("Transformer!", matrix: @matrix)
  ```
  """

  use Scenic.Primitive.Transform

  @matrix_byte_size 16 * 4

  # ============================================================================
  # data verification and serialization

  def validate(<<_::binary-size(@matrix_byte_size)>> = mx) do
    {:ok, mx}
  end

  def validate(data) do
    {
      :error,
      """
      #{IO.ANSI.red()}Invalid Matrix
      Received: #{inspect(data)}
      #{IO.ANSI.yellow()}
      Matrix data must be a binary containing 16 32-bit floats

      Please use the Scenic.Math.Matrix API to build this data.#{IO.ANSI.default_color()}
      """
    }
  end
end