Add core_3d_camera_split_screen

examples/core/core_3d_camera_split_screen.ml

@@ -0,0 +1,133 @@
+let screen_width = 800
+let screen_height = 450
+
+(* Grid data *)
+let count = 5
+let spacing = 4
+
+module Player = struct
+  type t = { camera : Raylib.Camera3D.t; screen : Raylib.RenderTexture.t }
+
+  let create ~pos:(pos_x, pos_y, pos_z) ~target:(tar_x, tar_y, tar_z) =
+    let open Raylib in
+    let position = Vector3.create pos_x pos_y pos_z in
+    let target = Vector3.create tar_x tar_y tar_z in
+    let up = Vector3.create 0. 1. 0. in
+    let fovy = 45. in
+    let projection = CameraProjection.Perspective in
+    let camera = Camera3D.create position target up fovy projection in
+    let screen = load_render_texture (screen_width / 2) screen_height in
+    { camera; screen }
+
+  let destroy t = Raylib.unload_render_texture t.screen
+
+  let handle_movements t ~key_up ~key_down vector =
+    (* If anyone moves this frame, how far will they move based on the time since the last frame
+       this moves thigns at 10 world units per second, regardless of the actual FPS *)
+    let open Raylib in
+    (* Move Player forward and backwards (no turning) *)
+    if is_key_down key_up then (
+      Camera3D.set_position t.camera
+        (Vector3.add vector @@ Camera3D.position t.camera);
+      Camera3D.set_target t.camera
+        (Vector3.add vector @@ Camera3D.target t.camera))
+    else if is_key_down key_down then (
+      Camera3D.set_position t.camera
+        (Vector3.subtract (Camera3D.position t.camera) vector);
+      Camera3D.set_target t.camera
+        (Vector3.subtract (Camera3D.target t.camera) vector))
+end
+
+type t = {
+  player_1 : Player.t;
+  player_2 : Player.t;
+  split_screen_rect : Raylib.Rectangle.t;
+}
+
+let setup () =
+  let open Raylib in
+  init_window screen_width screen_height
+    "raylib [core] example - 3d camera split screen";
+  let player_1 = Player.create ~pos:(0., 1., -3.) ~target:(0., 1., 0.) in
+  let player_2 = Player.create ~pos:(-3., 3., 0.) ~target:(0., 3., 0.) in
+  (* Build a flipped rectangle the size of the split view to use for drawing later *)
+  let split_screen_rect =
+    Rectangle.create 0. 0.
+      (Int.to_float @@ Texture2D.width @@ RenderTexture.texture player_1.screen)
+      (Int.to_float
+      @@ -(Texture2D.height @@ RenderTexture.texture player_1.screen))
+  in
+  set_target_fps 60;
+  { player_1; player_2; split_screen_rect }
+
+let draw_scene { player_1; player_2; split_screen_rect = _ } =
+  let open Raylib in
+  (* Draw scene: grid of cube trees on a plane to make a "world" *)
+  draw_plane (Vector3.create 0. 0. 0.) (Vector2.create 50. 50.) Color.beige;
+  for x = -count to count do
+    let x = x * spacing in
+    for z = -count to count do
+      let z = z * spacing in
+      draw_cube
+        (Vector3.create (Int.to_float x) 1.5 (Int.to_float z))
+        1. 1. 1. Color.lime;
+      draw_cube
+        (Vector3.create (Int.to_float x) 0.5 (Int.to_float z))
+        0.25 1. 0.25 Color.brown
+    done
+  done;
+  (* Draw a cube at each player's position *)
+  draw_cube (Camera3D.position player_1.camera) 1. 1. 1. Color.red;
+  draw_cube (Camera3D.position player_2.camera) 1. 1. 1. Color.blue
+
+let rec loop ({ player_1; player_2; split_screen_rect } as t) =
+  if Raylib.window_should_close () then (
+    Player.destroy player_1;
+    Player.destroy player_2;
+    Raylib.close_window ())
+  else
+    let open Raylib in
+    let offset_this_frame = 10. *. get_frame_time () in
+    Player.handle_movements player_1 ~key_up:W ~key_down:S
+      (Vector3.create 0. 0. offset_this_frame);
+    Player.handle_movements player_2 ~key_up:Up ~key_down:Down
+      (Vector3.create offset_this_frame 0. 0.);
+
+    (* Draw Player1 view to the render texture *)
+    begin_texture_mode player_1.screen;
+    clear_background Color.skyblue;
+    begin_mode_3d player_1.camera;
+    draw_scene t;
+    end_mode_3d ();
+    draw_rectangle 0 0 (get_screen_width () / 2) 40 (fade Color.raywhite 0.8);
+    draw_text "PLAYER1: W/S to move" 10 10 20 Color.maroon;
+    end_texture_mode ();
+
+    (* Draw Player2 view to the render texture *)
+    begin_texture_mode player_2.screen;
+    clear_background Color.skyblue;
+    begin_mode_3d player_2.camera;
+    draw_scene t;
+    end_mode_3d ();
+    draw_rectangle 0 0 (get_screen_width () / 2) 40 (fade Color.raywhite 0.8);
+    draw_text "PLAYER2: UP/DOWN to move" 10 10 20 Color.darkblue;
+    end_texture_mode ();
+
+    (* Draw both views render textures to the screen side by side *)
+    begin_drawing ();
+    clear_background Color.black;
+    draw_texture_rec
+      (RenderTexture.texture player_1.screen)
+      split_screen_rect (Vector2.create 0. 0.) Color.white;
+    draw_texture_rec
+      (RenderTexture.texture player_2.screen)
+      split_screen_rect
+      (Vector2.create (Int.to_float @@ (screen_width / 2)) 0.)
+      Color.white;
+    draw_rectangle
+      ((get_screen_width () / 2) - 2)
+      0 4 (get_screen_height ()) Color.lightgray;
+    end_drawing ();
+    loop t
+
+let () = setup () |> loop

examples/core/dune

@@ -33,6 +33,11 @@
  (modules Core_3d_camera_mode)
  (libraries raylib))
 
+(executable
+ (name core_3d_camera_split_screen)
+ (modules Core_3d_camera_split_screen)
+ (libraries raylib))
+
 (executable
  (name core_3d_picking)
  (modules Core_3d_picking)