Various.

- Map drawing is now possible with custom object-specific drawing
    code. A few examples have been added, including one that draws
    borders.
    Please note that those borders are still not perfect, however, as
    some inner angles are being rendered with plain/full-tile textures.
    The drawing code helpers will probably be moved to a location that
    makes them easy to reuse.
  - Some of the old map drawing code is still present (in particular in
    src/main.cr). That code is deprecated and will be removed soon.
  - WIP Naka::Map::ObjectReference. May or may not remain as it
    currently is.
  - Some mapgen updates to match the new drawing methods.
  - Possibly other minor tweaks or grooming.

src/main.cr

@@ -4,9 +4,7 @@ require "json"
 require "./naka.cr"
 
 class ImagesLoader
-	getter grass : SDL::Texture
 	getter stone : SDL::Texture
-	getter dirt  : SDL::Texture
 	getter tree  : SDL::Texture
 	getter pine  : SDL::Texture
 	getter flowers  : SDL::Texture
@@ -16,9 +14,7 @@ class ImagesLoader
 	getter rocks  : SDL::Texture
 
 	def initialize(window)
-		@grass = window.newImage "assets/grass.png"
 		@stone = window.newImage "assets/stone.png"
-		@dirt  = window.newImage "assets/dirt.png"
 		@tree  = window.newImage "assets/tree.png"
 		@flowers  = window.newImage "assets/flowers.png"
 		@sand  = window.newImage "assets/sand.png"
@@ -38,6 +34,114 @@ images = ImagesLoader.new window
 connection_font = window.newFont "assets/connection.otf", 30.5
 window.set_font connection_font
 
+def simple_tile_drawer(window : Naka::Window, tile_path : String)
+	texture = window.newImage tile_path
+
+	->(map : Naka::Map, x : Int32, y : Int32, z : Int32, tile : Naka::Map::Tile, object : Naka::Map::Object, draw_x : Int32, draw_y : Int32, zoom : Float64){
+		window.draw texture, draw_x, draw_y, scale_x: zoom, scale_y: zoom
+		nil
+	}
+end
+
+def bordered_tile_drawer(window : Naka::Window, base_tile_path : String)
+	# FIXME: Both excessive, insufficient, and broken.
+
+	mod = [
+		"trbl",
+		"-rbl",
+		"t-bl",
+		"tr-l",
+		"trb-",
+		"t-b-",
+		"-r-l",
+		"tr--",
+		"-rb-",
+		"--bl",
+		"t--l",
+		"t---",
+		"-r--",
+		"--b-",
+		"---l",
+		"----"
+	]
+
+	textures = Hash(String, SDL::Texture).new
+
+	mod.each do |s|
+		begin
+			textures[s] = window.newImage base_tile_path.sub /{}/, "-" + s
+		rescue
+			# Not even sure we should be doing something here…
+			# Maybe in the future, in debug mode?
+		end
+	end
+
+	->(map : Naka::Map, x : Int32, y : Int32, z : Int32, tile : Naka::Map::Tile, object : Naka::Map::Object, draw_x : Int32, draw_y : Int32, zoom : Float64){
+		neighbours = [
+			{x,   y-1, "t"},
+			{x+1, y,   "r"},
+			{x,   y+1, "b"},
+			{x-1, y,   "l"}
+		]
+
+		neighbours = neighbours.map do |x, y|
+			map.get(x, y)[z]?.try &.reference.== object.reference
+		end
+
+		t, r, b, l = neighbours
+		t = t ? 't' : '-'
+		r = r ? 'r' : '-'
+		b = b ? 'b' : '-'
+		l = l ? 'l' : '-'
+
+		neighbours = [t, r, b, l].reduce "" { |a, c| a + c }
+
+		window.draw (textures[neighbours]? || textures["trbl"]), draw_x, draw_y, scale_x: zoom, scale_y: zoom
+
+		nil
+	}
+end
+
+stone =    Naka::Map::ObjectReference.new(
+	name: "Stone",
+	walkable: true,
+	drawer: simple_tile_drawer window, "assets/stone.png"
+)
+grass =    Naka::Map::ObjectReference.new(
+	name: "Grass",
+	walkable: true,
+	drawer: bordered_tile_drawer window, "assets/grass{}.png"
+)
+dirt =     Naka::Map::ObjectReference.new(
+	name: "Dirt",
+	walkable: true,
+	drawer: bordered_tile_drawer window, "assets/dirt{}.png"
+)
+sand =     Naka::Map::ObjectReference.new(
+	name: "Sand",
+	walkable: true
+)
+water =    Naka::Map::ObjectReference.new(
+	name: "Water"
+)
+flowers =  Naka::Map::ObjectReference.new(
+	name: "Flowers",
+	walkable: true
+)
+haunted =  Naka::Map::ObjectReference.new(
+	name: "Haunted",
+	walkable: true
+)
+tree =     Naka::Map::ObjectReference.new(
+	name: "Tree"
+)
+pine =     Naka::Map::ObjectReference.new(
+	name: "Pine Tree"
+)
+rocks =    Naka::Map::ObjectReference.new(
+	name: "Rocks"
+)
+
 altitude_noise = Naka::Noise2D.new.tap do |a|
 	a.add_octave(32, 1)
 	a.add_octave(16, 0.5)
@@ -61,55 +165,61 @@ evil_noise = Naka::Noise2D.new.tap do |a|
 	a.add_octave(16, 0.3)
 end
 
-map = Naka::Map.new "map-test-01" do |tile, x, y|
+map = Naka::Map.new stone, "map-test-01" do |tile, x, y|
 	altitude = altitude_noise.get(x, y) + 0.5
 
 	humidity = humidity_noise.get(x, y) + 0.5
 
 	evil = evil_noise.get(x, y)
 
-	if altitude < 0.25
-		tile << Naka::Map::Object.new "sand"
+	if altitude < 0.35
+		tile << Naka::Map::Object.new water
+	else
+		tile << Naka::Map::Object.new stone
+	end
 
-		if altitude < 0.175
-			tile << Naka::Map::Object.new "water"
-		else
+	if altitude < 0.25
+		if altitude > 0.175
 			if humidity < 0.33
-				tile << Naka::Map::Object.new "sand"
+				tile << Naka::Map::Object.new sand
 			else
-				tile << Naka::Map::Object.new "dirt"
+				tile << Naka::Map::Object.new dirt
 			end
 		end
 	elsif altitude < 0.75
-		tile << Naka::Map::Object.new "dirt"
+		tile << Naka::Map::Object.new dirt
 
 		if evil > 0.5
-			tile << Naka::Map::Object.new "haunted"
+			tile << Naka::Map::Object.new haunted
 		else
-			tile << Naka::Map::Object.new "grass"
+			tile << Naka::Map::Object.new grass
 		end
 
 		if altitude > 0.35 && altitude < 0.65
 			if humidity > 0.4
 				if humidity > 0.8
-					tile << Naka::Map::Object.new "tree"
+					tile << Naka::Map::Object.new tree
 				elsif humidity < 0.6
-					tile << Naka::Map::Object.new "pine"
+					tile << Naka::Map::Object.new pine
 				else
 					if Random.rand(2) == 0
-						tile << Naka::Map::Object.new "tree"
+						tile << Naka::Map::Object.new tree
 					else
-						tile << Naka::Map::Object.new "pine"
+						tile << Naka::Map::Object.new pine
 					end
 				end
 			else
 				if Random.rand(10) == 0
-					tile << Naka::Map::Object.new "flowers"
+					tile << Naka::Map::Object.new flowers
 				end
 			end
 		end
-	elsif altitude > 0.85
-		tile << Naka::Map::Object.new "rocks"
+	else
+		tile << Naka::Map::Object.new stone
+
+		if altitude > 0.85
+			tile << Naka::Map::Object.new rocks
+		end
 	end
 end
 
@@ -119,7 +229,7 @@ Naka::Event.loop window do |event|
 		next Naka::Event::Quit
 	when Naka::Event::Update
 	when Naka::Event::Draw
-		zoom_level = 1.0
+		zoom_level = 4.0
 
 		128.times do |x|
 			128.times do |y|
@@ -128,17 +238,11 @@ Naka::Event.loop window do |event|
 				# FIXME:
 				#   - Please don’t draw more than one layer of ground…
 				#   - Transitions. (eg. between dirt and grass)
-				tile.each do |object|
-					image = case object.type
-					when "grass"
-						images.grass
-					when "dirt"
-						images.dirt
-					when "stone"
-						images.stone
+				tile.each_with_index do |object, z|
+					image = case object.reference.name.downcase
 					when "tree"
 						images.tree
-					when "pine"
+					when "pine tree"
 						images.pine
 					when "flowers"
 						images.flowers
@@ -154,13 +258,23 @@ Naka::Event.loop window do |event|
 						images.stone
 					end
 
-					window.draw(
-						image,
-						x: (x * 16 * zoom_level).to_i,
-						y: (y * 16 * zoom_level - (image.height - 16) * zoom_level).to_i,
-						scale_x: zoom_level,
-						scale_y: zoom_level
-					)
+					draw_x = (x * 16 * zoom_level).to_i
+					draw_y = (y * 16 * zoom_level - (image.height - 16) * zoom_level).to_i
+
+					drawer = object.reference.drawer
+
+					if drawer.nil?
+						window.draw(
+							image,
+							x: draw_x,
+							y: draw_y,
+							scale_x: zoom_level,
+							scale_y: zoom_level
+						)
+						next
+					end
+
+					drawer.call map, x, y, z, tile, object, draw_x, draw_y, zoom_level
 				end
 			end
 		end

src/naka/map.cr

@@ -3,21 +3,33 @@ require "json"
 
 class Naka::Map
 	@save_directory : String
+	getter default_reference : ObjectReference
 	getter generator
-	def initialize(@save_directory, &block : Proc(Tile, Int32, Int32, Tile?))
+
+	def initialize(@default_reference, @save_directory, &block : Proc(Tile, Int32, Int32, Tile?))
 		Dir.mkdir_p @save_directory
 
 		@generator = block
 	end
 
+	class ObjectReference
+		getter name : String
+		getter walkable : Bool
+		getter tiles : Array(String)
+		getter drawer : Proc(Map, Int32, Int32, Int32, Tile, Object, Int32, Int32, Float64, Nil)?
+
+		def initialize(@name, @walkable = false, @tiles = [] of String, @drawer = nil)
+		end
+	end
+
 	class Object
-		getter type : String
-		def initialize(@type)
+		getter reference : ObjectReference
+		def initialize(@reference)
 		end
 
 		def to_json(builder)
 			builder.object do
-				builder.field "type", @type
+				builder.field "type", @reference.name
 			end
 		end
 	end
@@ -45,7 +57,7 @@ class Naka::Map
 				Array.new(CHUNK_SIZE) do |y|
 					y += @y * CHUNK_SIZE
 
-					Tile.new(Object.new "stone").tap do |tile|
+					Tile.new(Object.new map.default_reference).tap do |tile|
 						map.generator.call tile, x, y
 					end
 				end