draw.ml

open Object
open Sprite
module Html = Dom_html
let document = Html.document
let jstr = Js.string

let get_context canvas = canvas##getContext (Dom_html._2d_)

let render_bbox sprite (posx,posy) =
  let context = sprite.context in
  let (bbox,bboy) = sprite.params.bbox_offset in
  let (bbsx,bbsy) = sprite.params.bbox_size in
  context##strokeStyle <- Js.string "#FF0000";
  context##strokeRect(posx+.bbox,posy+.bboy,bbsx,bbsy)

(*Draws a sprite onto the canvas.*)
let render sprite (posx,posy) =
  let context = sprite.context in
  let (sx, sy) = sprite.params.src_offset in
  let (sw, sh) = sprite.params.frame_size in
  let (dx, dy) = (posx,posy) in
  let (dw, dh) = sprite.params.frame_size in
  let sx = sx +. (float_of_int !(sprite.frame)) *. sw in
  (*print_endline (string_of_int !(sprite.frame));*)
  (*context##clearRect(0.,0.,sw, sh);*)
  context##drawImage_full(sprite.img, sx, sy, sw, sh, dx, dy, dw, dh)

(*Draws two background images, which needs to be done because of the
 *constantly changing viewport, which is always at most going to be
 *between two background images.*)
let draw_bgd bgd off_x =
  render bgd (~-.off_x,0.);
  render bgd ((fst bgd.params.frame_size) -. off_x, 0.)

(*Used for animation updating. Canvas is cleared each frame and redrawn.*)
let clear_canvas canvas =
  let context = canvas##getContext (Dom_html._2d_) in
  let cwidth = float_of_int canvas##width in
  let cheight = float_of_int canvas##height in
  ignore context##clearRect(0.,0.,cwidth,cheight)

(*Displays the text for score and coins.*)
let hud canvas score coins =
  let score_string = string_of_int score in
  let coin_string = string_of_int coins in
  let context = canvas##getContext (Dom_html._2d_) in
  ignore context##font <- (Js.string ("10px 'Press Start 2P'"));
  ignore context##fillText (Js.string ("Score: "^score_string), (float_of_int canvas##width) -. 140., 18.);
  ignore context##fillText (Js.string ("Coins: "^coin_string), 120., 18.)

(*Displays the fps.*)
let fps canvas fps_val =
  let fps_str = int_of_float fps_val |> string_of_int in
  let context = canvas##getContext (Dom_html._2d_) in
  ignore context##fillText (Js.string fps_str, 10.,18.)

(*game_win displays a black screen when you finish a game.*)
let game_win ctx =
  ctx##rect (0.,0.,512.,512.);
  ctx##fillStyle <- (Js.string "black");
  ctx##fill ();
  ctx##fillStyle <- (Js.string "white");
  ctx##font <- (Js.string "20px 'Press Start 2P'");
  ctx##fillText (Js.string ("You win!"), 180., 128.);
  failwith "Game over."

(*gave_loss displays a black screen stating a loss to finish that level play.*)
let game_loss ctx =
  ctx##rect (0.,0.,512.,512.);
  ctx##fillStyle <- (Js.string "black");
  ctx##fill ();
  ctx##fillStyle <- (Js.string "white");
  ctx##font <- (Js.string "20px 'Press Start 2P'");
  ctx##fillText (Js.string ("GAME OVER. You lose!"), 60., 128.);
  failwith "Game over."

let draw_background_color canvas = failwith "todo"
let debug f = Printf.ksprintf (fun s -> Firebug.console##log (jstr s)) f
let alert f = Printf.ksprintf (fun s -> Dom_html.window##alert(Js.string s); failwith "poo") f