# plate.ludic - the stage: a flat disc 40 m across at y = 0 with a line every metre, lit by the
# package's own small sky (a sun 40 degrees up), and nothing else. Its files are in plate/.

# the package's plate/ directory: beside the project (a checkout of the toolchain) or installed
export function lab_plate_dir(lab_st: mut LabState) -> string {
  if lab_st.lb_plate_dir != "" { return lab_st.lb_plate_dir }
  lab_st.lb_plate_dir = "packages/ludic.lab/plate"
  if not Fs.exists(`{lab_st.lb_plate_dir}/plate.gltf`) { lab_st.lb_plate_dir = `{r3d_home()}/packages/ludic.lab/plate` }
  return lab_st.lb_plate_dir
}
function lab_plate_load(lab_st: mut LabState, render3d_st: mut Render3dState) -> void {
  let m = gltf_load(render3d_st, lab_plate_dir(lab_st), "plate.gltf", "plate")
  if m == null { return }
  lab_st.lb_plate = actor_new(render3d_st, m)
  lab_st.lb_plate.casts = false
  lab_st.lb_plate.cull = 0.0
  lab_st.lb_plate.radius = 0.0
  actor_place(lab_st.lb_plate, 0.0, 0.0, 0.0, 0.0)
}
# the ground under (x, z): the plate is flat at 0
export function lab_ground_y(x: float, z: float) -> float { return 0.0 }
# an actor stood on the plate at (x, z), facing yaw (radians)
export function lab_stand(a: Actor, x: float, z: float, yaw: float) -> void {
  if a == null { return }
  actor_place(a, x, lab_ground_y(x, z), z, yaw)
}
# a model from a glTF file stood on the plate: the one call a scene usually needs
export function lab_model(render3d_st: mut Render3dState, dir: string, file: string, node: string, x: float, z: float, yaw: float) -> Actor {
  let m = gltf_load(render3d_st, dir, file, node)
  if m == null { return null }
  let a = actor_new(render3d_st, m)
  lab_stand(a, x, z, yaw)
  return a
}