Create mapgen step func

Author: bluddy

src/game.ml

@@ -68,6 +68,7 @@ end
 
 type state = {
   random: Random.State.t;
+  random_seed: int;
   game: game;
   screen: Screen.t;
   resources: resources;
@@ -77,6 +78,8 @@ type state = {
 
 let run ?(view=Screen.MapGen None) ?(area=Gmap.WestUS) () : unit =
   let random = Random.get_state () in
+  (* Used by different elements *)
+  let random_seed = Random.int 0x7FFF random in
 
   Printf.printf "Loading resources...";
 
@@ -96,7 +99,7 @@ let run ?(view=Screen.MapGen None) ?(area=Gmap.WestUS) () : unit =
     let game = {map; area; cities} in
 
     let textures = Textures.of_resources win resources area in
-    let state = {game; screen; resources; random; textures} in
+    let state = {game; screen; resources; random; textures; random_seed} in
 
     Printf.printf " done.\n";
 
@@ -106,10 +109,11 @@ let run ?(view=Screen.MapGen None) ?(area=Gmap.WestUS) () : unit =
         | Screen.MapGen None ->
             (* Prepare mapgen with init *)
             let cities = List.assoc ~eq:(Gmap.equal_area) area s.resources.res_cities in
-            let data = Mapgen.init s.random s.game.area cities in
+            let data = Mapgen.init s.random s.game.area cities ~random_seed in
             Lens.Infix.((state_screen |-- Screen.view) ^= Screen.MapGen(Some data)) state
 
         | Screen.MapGen Some data -> s
+
         | _ -> s
       in
       state, false
@@ -126,6 +130,7 @@ let run ?(view=Screen.MapGen None) ?(area=Gmap.WestUS) () : unit =
             Result.return ()
           in
           s
+
       | Screen.MapGen None -> s
     in
     state, Graphics.{update; render}

src/gmap.ml

@@ -69,7 +69,7 @@ type pixel =
   | EnemyRR_pixel
   | City_pixel
   | Mountain_pixel (* 15 *)
-  [@@deriving enum]
+  [@@deriving enum, eq]
 
 let pixel_of_tile = function
   | Slums -> Slum_pixel
@@ -122,13 +122,10 @@ let tile_of_pixel_default = function
 let map_height = 192
 let map_width = 256
 
-let calc_offset x y = y * map_width + x
-let read_map map x y = map.(calc_offset x y)
-
 (* random_seed: 15 bits from time *)
 let tile_of_pixel ~x ~y ~pixel ~random_seed =
   let xy_random = x * 9 + y * 13 + random_seed in
-  let pixel = Option.get @@ pixel_of_enum pixel in
+  (* let pixel = Option.get @@ pixel_of_enum pixel in *)
   let simple_mapping = function
     | Slum_pixel -> Slums
     | Ocean_pixel -> Ocean
@@ -226,3 +223,15 @@ let to_img map =
   let ndarray = to_ndarray map in
   Pic.img_of_ndarray ndarray
 
+let calc_offset x y = y * map_width + x
+
+let get_tile map x y = map.(calc_offset x y)
+
+let get_pixel ~map ~x ~y = get_tile map x y |> pixel_of_tile
+
+let set_pixel ~map ~x ~y ~pixel ~random_seed =
+  let tile = tile_of_pixel ~x ~y ~pixel ~random_seed in
+  map.(calc_offset x y) <- tile
+
+
+

src/mapgen.ml

@@ -3,7 +3,7 @@ open Gmap
 
 let debug = false
 
-let add_mountain_pixel = function
+let pixel_apply_mountain = function
   | Foothills_pixel -> Hills_pixel
   | Hills_pixel -> Mountain_pixel
   | Ocean_pixel
@@ -147,7 +147,7 @@ let add_mountains_list r area =
      This particular function needs to access the map, and since resources can only 
      be in certain tiles, it may fail and need to try again and again.
    *)
-let add_resource area ~map ~land_type ~resource_pixel ~wanted_tile ~random_seed ~r =
+let add_resource area ~map ~land_pixel ~resource_pixel ~wanted_tile ~random_seed ~r =
   let rec loop () =
     let x = Random.int 256 r in
     let y = Random.int 192 r in
@@ -159,21 +159,21 @@ let add_resource area ~map ~land_type ~resource_pixel ~wanted_tile ~random_seed
       | Europe -> x
     in
     let rec attempt i x y =
-      if i >= 2 then false else
-      let offset = calc_offset x y in
-      let tile = map.(offset) in
+      if i >= 2 then None else
+      let pixel = Gmap.get_pixel ~map ~x ~y in
       let possible_tile = tile_of_pixel ~x ~y ~random_seed ~pixel:resource_pixel in
-      if Gmap.equal_tile tile land_type && Gmap.equal_tile possible_tile wanted_tile then (
-        map.(offset) <- possible_tile;
-        true
+      if Gmap.equal_pixel pixel land_pixel && Gmap.equal_tile possible_tile wanted_tile then (
+        Gmap.set_pixel ~map ~x ~y ~pixel:resource_pixel ~random_seed;
+        Some (x, y)
       ) else
         let x = if y mod 2 = 1 then x + 1 else x - 1 in
         attempt (i + 1) x (y + 1)
     in
-    if attempt 0 x y then ()
-    else loop ()   (* Keep trying *)
+    match attempt 0 x y with
+    | None -> loop ()
+    | x -> x
   in
-  loop ()
+  loop () |> Option.get_exn_or "Impossible failure reached"
 
   (* A general list of resources to add *)
 let add_resources_list area =
@@ -192,7 +192,7 @@ let add_resources_list area =
         (Clear_pixel, OilWell_pixel, OilWell, count);
       ]
 
-let upgrade_city_pixel = function
+let pixel_apply_city = function
   | Clear_pixel
   | Woods_pixel
   | Farm_pixel -> Village_pixel
@@ -260,17 +260,62 @@ let load_city_list ?(debug=false) area  =
   cities
 
 type t = {
+  area: area;
   mountains : (int * int) list;
   resources: (pixel * pixel * tile * int) list;
   cities: (int * int) list;
   current: [`Mountains | `Resources | `Cities];
+  new_pixels: (int * int * pixel) list;
+  random_seed: int;
 }
 
-let init r area cities =
+let init r area cities ~random_seed =
   let mountains = add_mountains_list r area in
   let resources = add_resources_list area in
   let cities = add_city_list r area cities in
   let current = `Mountains in
-  {mountains; resources; cities; current}
+  let new_pixels = [] in
+  {area; mountains; resources; cities; current; new_pixels; random_seed}
+
+  (* Perform a step of updating the map *)
+let update_map_step r v map =
+  let random_seed = v.random_seed in
+  let is_done = false in
+  match v.current with
+  | `Mountains -> 
+      begin match v.mountains with
+      | (x, y)::rest ->
+          let pixel = Gmap.get_pixel ~map ~x ~y in
+          let pixel = pixel_apply_mountain pixel in
+          Gmap.set_pixel ~map ~x ~y ~pixel ~random_seed;
+          let new_pixels = (x, y, pixel)::v.new_pixels in
+          {v with mountains=rest; new_pixels}, is_done
+      | _ ->
+          {v with current=`Resources}, is_done
+      end
+  | `Cities ->
+      begin match v.cities with
+      | (x, y)::rest ->
+          let pixel = Gmap.get_pixel ~map ~x ~y in
+          let pixel = pixel_apply_city pixel in
+          Gmap.set_pixel ~map ~x ~y ~pixel ~random_seed;
+          let new_pixels = (x, y, pixel)::v.new_pixels in
+          {v with cities=rest; new_pixels}, is_done
+      | _ -> v, true
+      end
+  | `Resources ->
+      begin match v.resources with
+      | (_, _, _, 0)::rest ->
+          {v with resources=rest}, is_done
+      | (land_pixel, resource_pixel, wanted_tile, num)::rest ->
+          let x, y =
+            add_resource v.area ~map ~land_pixel ~resource_pixel ~wanted_tile ~random_seed ~r
+          in
+          let new_pixels = (x, y, resource_pixel)::v.new_pixels in
+          let resources = (land_pixel, resource_pixel, wanted_tile, num-1)::rest in
+          {v with resources; new_pixels}, is_done
+      | _ -> {v with current=`Cities}, is_done
+      end
+