Province index and colour lookup texture

8 files changed, 224 insertions, 48 deletions

diff --git a/extension/src/MapMesh.cpp b/extension/src/MapMesh.cpp
index 2fa6be4..cdbeec9 100644
--- a/extension/src/MapMesh.cpp
+++ b/extension/src/MapMesh.cpp
@@ -19,6 +19,7 @@ void MapMesh::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_subdivide_depth"), &MapMesh::get_subdivide_depth);
 
 	ClassDB::bind_method(D_METHOD("get_core_aabb"), &MapMesh::get_core_aabb);
+	ClassDB::bind_method(D_METHOD("is_valid_uv_coord"), &MapMesh::is_valid_uv_coord);
 
 	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "aspect_ratio", PROPERTY_HINT_NONE, "suffix:m"), "set_aspect_ratio", "get_aspect_ratio");
 	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "repeat_proportion", PROPERTY_HINT_NONE, "suffix:m"), "set_repeat_proportion", "get_repeat_proportion");
@@ -72,6 +73,10 @@ AABB MapMesh::get_core_aabb() const {
 	return AABB{ size * -0.5f, size };
 }
 
+bool MapMesh::is_valid_uv_coord(godot::Vector2 const& uv) const {
+	return -repeat_proportion <= uv.x && uv.x <= 1.0f + repeat_proportion && 0.0f <= uv.y && uv.y <= 1.0f;
+}
+
 Array MapMesh::_create_mesh_array() const {
 	Array arr;
 	arr.resize(Mesh::ARRAY_MAX);
diff --git a/extension/src/MapMesh.hpp b/extension/src/MapMesh.hpp
index 5427894..d8727cf 100644
--- a/extension/src/MapMesh.hpp
+++ b/extension/src/MapMesh.hpp
@@ -27,6 +27,7 @@ namespace OpenVic2 {
 		int get_subdivide_depth() const;
 
 		godot::AABB get_core_aabb() const;
+		bool is_valid_uv_coord(godot::Vector2 const& uv) const;
 
 		godot::Array _create_mesh_array() const override;
 	};
diff --git a/extension/src/MapSingleton.cpp b/extension/src/MapSingleton.cpp
index 9d13496..71977da 100644
--- a/extension/src/MapSingleton.cpp
+++ b/extension/src/MapSingleton.cpp
@@ -12,8 +12,11 @@ MapSingleton* MapSingleton::singleton = nullptr;
 void MapSingleton::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("load_province_identifier_file", "file_path"), &MapSingleton::load_province_identifier_file);
 	ClassDB::bind_method(D_METHOD("load_province_shape_file", "file_path"), &MapSingleton::load_province_shape_file);
-	ClassDB::bind_method(D_METHOD("get_province_shape_image"), &MapSingleton::get_province_shape_image);
-	ClassDB::bind_method(D_METHOD("get_province_identifier_from_colour", "colour"), &MapSingleton::get_province_identifier_from_colour);
+	ClassDB::bind_method(D_METHOD("get_province_identifier_from_pixel_coords", "coords"), &MapSingleton::get_province_identifier_from_pixel_coords);
+	ClassDB::bind_method(D_METHOD("get_width"), &MapSingleton::get_width);
+	ClassDB::bind_method(D_METHOD("get_height"), &MapSingleton::get_height);
+	ClassDB::bind_method(D_METHOD("get_province_index_image"), &MapSingleton::get_province_index_image);
+	ClassDB::bind_method(D_METHOD("get_province_colour_image"), &MapSingleton::get_province_colour_image);
 }
 
 MapSingleton* MapSingleton::get_singleton() {
@@ -105,20 +108,17 @@ Error MapSingleton::load_province_identifier_file(String const& file_path) {
 			continue;
 		}
 		std::string error_message;
-		if (map.add_province(identifier.utf8().get_data(), colour, error_message)) {
-			UtilityFunctions::print(error_message.c_str());
-		} else {
+		if (!map.add_province(identifier.utf8().get_data(), colour, error_message)) {
 			UtilityFunctions::push_error(error_message.c_str());
 			err = FAILED;
 		}
 	}
+	map.lock_provinces();
 	return err;
 }
 
-String MapSingleton::get_province_identifier_from_colour(Province::colour_t colour) {
-	const Province* province = map.get_province_by_colour(colour);
-	if (province) return province->get_identifier().c_str();
-	else return String{};
+static Province::colour_t colour_at(PackedByteArray const& colour_data_array, int32_t idx) {
+	return (colour_data_array[idx * 3] << 16) | (colour_data_array[idx * 3 + 1] << 8) | colour_data_array[idx * 3 + 2];
 }
 
 Error MapSingleton::load_province_shape_file(String const& file_path) {
@@ -133,13 +133,13 @@ Error MapSingleton::load_province_shape_file(String const& file_path) {
 		province_shape_image.unref();
 		return err;
 	}
-	int32_t width = province_shape_image->get_width();
-	int32_t height = province_shape_image->get_height();
+	width = province_shape_image->get_width();
+	height = province_shape_image->get_height();
 	if (width < 1 || height < 1) {
 		UtilityFunctions::push_error("Invalid dimensions (", width, "x", height, ") for province shape file: ", file_path);
 		err = FAILED;
 	}
-	static const Image::Format expected_format = Image::Format::FORMAT_RGB8; 
+	static const Image::Format expected_format = Image::FORMAT_RGB8;
 	Image::Format format = province_shape_image->get_format();
 	if (format != expected_format) {
 		UtilityFunctions::push_error("Invalid format (", format, ", should be ", expected_format, ") for province shape file: ", file_path);
@@ -149,9 +149,106 @@ Error MapSingleton::load_province_shape_file(String const& file_path) {
 		province_shape_image.unref();
 		return err;
 	}
+
+	std::vector<bool> province_checklist(map.get_province_count());
+
+	PackedByteArray shape_data_array = province_shape_image->get_data(), index_data_array;
+	index_data_array.resize(width * height * sizeof(Province::index_t));
+	Province::index_t* index_data = reinterpret_cast<Province::index_t*>(index_data_array.ptrw());
+
+	for (int32_t y = 0; y < height; ++y) {
+		for (int32_t x = 0; x < width; ++x) {
+			const int32_t idx = x + y * width;
+			const Province::colour_t colour = colour_at(shape_data_array, idx);
+			if (colour == Province::NULL_COLOUR) {
+				index_data[idx] = Province::NULL_INDEX;
+				continue;
+			}
+			if (x > 0) {
+				const int32_t jdx = idx - 1;
+				if (colour_at(shape_data_array, jdx) == colour) {
+					index_data[idx] = index_data[jdx];
+					continue;
+				}
+			}
+			if (y > 0) {
+				const int32_t jdx = idx - width;
+				if (colour_at(shape_data_array, jdx) == colour) {
+					index_data[idx] = index_data[jdx];
+					continue;
+				}
+			}
+			const Province* province = map.get_province_by_colour(colour);
+			if (province) {
+				Province::index_t index = province->get_index();
+				index_data[idx] = index;
+				province_checklist[index - 1] = true;
+				continue;
+			}
+			UtilityFunctions::push_error("Unrecognised province colour ", Province::colour_to_hex_string(colour).c_str(), " at (", x, ", ", y, ")");
+			err = FAILED;
+			index_data[idx] = Province::NULL_INDEX;
+		}
+	}
+
+	for (size_t idx = 0; idx < province_checklist.size(); ++idx) {
+		if (!province_checklist[idx]) {
+			Province* province = map.get_province_by_index(idx + 1);
+			if (province) UtilityFunctions::push_error("Province missing from shape image: ", province->to_string().c_str());
+			else UtilityFunctions::push_error("Province missing for index: ", idx + 1);
+			err = FAILED;
+		}
+	}
+
+	province_index_image = Image::create_from_data(width, height, false, Image::FORMAT_RG8, index_data_array);
+	if (province_index_image.is_null()) {
+		UtilityFunctions::push_error("Failed to create province ID image");
+		err = FAILED;
+	}
+
+	PackedByteArray colour_data_array;
+	colour_data_array.resize((Province::MAX_INDEX + 1) * 3);
+	for (int64_t idx = 1; idx <= map.get_province_count(); ++idx) {
+		const Province* province = map.get_province_by_index(idx);
+		if (province) {
+			const Province::colour_t colour = province->get_colour();
+			colour_data_array[3 * idx + 0] = (colour >> 16) & 0xFF;
+			colour_data_array[3 * idx + 1] = (colour >> 8) & 0xFF;
+			colour_data_array[3 * idx + 2] = colour & 0xFF;
+		} else UtilityFunctions::push_error("Missing province at index ", idx);
+	}
+	static const int32_t PROVINCE_INDEX_SQRT = 1 << (sizeof(Province::index_t) * 4);
+	province_colour_image = Image::create_from_data(PROVINCE_INDEX_SQRT, PROVINCE_INDEX_SQRT, false, Image::FORMAT_RGB8, colour_data_array);
+	if (province_colour_image.is_null()) {
+		UtilityFunctions::push_error("Failed to create province colour image");
+		err = FAILED;
+	}
+
 	return err;
 }
 
-Ref<Image> MapSingleton::get_province_shape_image() const {
-	return province_shape_image;
+String MapSingleton::get_province_identifier_from_pixel_coords(Vector2i const& coords) {
+	if (province_index_image.is_valid() && 0 <= coords.x && coords.x < width && 0 <= coords.y && coords.y < height) {
+		const PackedByteArray index_data_array = province_index_image->get_data();
+		const Province::index_t* index_data = reinterpret_cast<const Province::index_t*>(index_data_array.ptr());
+		const Province* province = map.get_province_by_colour(index_data[coords.x + coords.y * width]);
+		if (province) return province->get_identifier().c_str();
+	}
+	return String{};
+}
+
+int32_t MapSingleton::get_width() const {
+	return width;
+}
+
+int32_t MapSingleton::get_height() const {
+	return height;
+}
+
+Ref<Image> MapSingleton::get_province_index_image() const {
+	return province_index_image;
+}
+
+Ref<Image> MapSingleton::get_province_colour_image() const {
+	return province_colour_image;
 }
diff --git a/extension/src/MapSingleton.hpp b/extension/src/MapSingleton.hpp
index fb62e11..71761cd 100644
--- a/extension/src/MapSingleton.hpp
+++ b/extension/src/MapSingleton.hpp
@@ -10,7 +10,8 @@ namespace OpenVic2 {
 
 		static MapSingleton* singleton;
 
-		godot::Ref<godot::Image> province_shape_image;
+		godot::Ref<godot::Image> province_shape_image, province_index_image, province_colour_image;
+		int32_t width = 0, height = 0;
 		Map map;
 
 	protected:
@@ -24,7 +25,10 @@ namespace OpenVic2 {
 
 		godot::Error load_province_identifier_file(godot::String const& file_path);
 		godot::Error load_province_shape_file(godot::String const& file_path);
-		godot::String get_province_identifier_from_colour(Province::colour_t colour);
-		godot::Ref<godot::Image> get_province_shape_image() const;
+		godot::String get_province_identifier_from_pixel_coords(godot::Vector2i const& coords);
+		int32_t get_width() const;
+		int32_t get_height() const;
+		godot::Ref<godot::Image> get_province_index_image() const;
+		godot::Ref<godot::Image> get_province_colour_image() const;
 	};
 }
diff --git a/extension/src/openvic2/Map.cpp b/extension/src/openvic2/Map.cpp
index 542a876..d980b88 100644
--- a/extension/src/openvic2/Map.cpp
+++ b/extension/src/openvic2/Map.cpp
@@ -1,12 +1,17 @@
 #include "Map.hpp"
 
+#include <cassert>
 #include <sstream>
 #include <iomanip>
 
 using namespace OpenVic2;
 
-Province::Province(std::string const& new_identifier, colour_t new_colour) :
-	identifier(new_identifier), colour(new_colour) {}
+Province::Province(index_t new_index, std::string const& new_identifier, colour_t new_colour) :
+	index(new_index), identifier(new_identifier), colour(new_colour) {
+	assert(index != NULL_INDEX);
+	assert(!identifier.empty());
+	assert(colour != NULL_COLOUR);
+}
 
 std::string Province::colour_to_hex_string(colour_t colour) {
 	std::ostringstream stream;
@@ -14,6 +19,10 @@ std::string Province::colour_to_hex_string(colour_t colour) {
 	return stream.str();
 }
 
+Province::index_t Province::get_index() const {
+	return index;
+}
+
 std::string const& Province::get_identifier() const {
 	return identifier;
 }
@@ -23,15 +32,23 @@ Province::colour_t Province::get_colour() const {
 }
 
 std::string Province::to_string() const {
-	return "(" + identifier + ", " + colour_to_hex_string(colour) + ")";
+	return "(#" + std::to_string(index) + ", " + identifier + ", 0x" + colour_to_hex_string(colour) + ")";
 }
 
 bool Map::add_province(std::string const& identifier, Province::colour_t colour, std::string& error_message) {
+	if (provinces_locked) {
+		error_message = "The map's province list has already been locked!";
+		return false;
+	}
+	if (provinces.size() >= Province::MAX_INDEX) {
+		error_message = "The map's province list is full - there can be at most " + std::to_string(Province::MAX_INDEX) + " provinces";
+		return false;
+	}
 	if (colour == Province::NULL_COLOUR || colour > Province::MAX_COLOUR) {
 		error_message = "Invalid province colour: " + Province::colour_to_hex_string(colour);
 		return false;
 	}
-	Province new_province{ identifier, colour };
+	Province new_province{ static_cast<Province::index_t>(provinces.size() + 1), identifier, colour };
 	for (Province const& province : provinces) {
 		if (province.identifier == identifier) {
 			error_message = "Duplicate province identifiers: " + province.to_string() + " and " + new_province.to_string();
@@ -47,6 +64,18 @@ bool Map::add_province(std::string const& identifier, Province::colour_t colour,
 	return true;
 }
 
+void Map::lock_provinces() {
+	provinces_locked = true;
+}
+
+size_t Map::get_province_count() const {
+	return provinces.size();
+}
+
+Province* Map::get_province_by_index(Province::index_t index) {
+	return index != Province::NULL_INDEX && index <= provinces.size() ? &provinces[index - 1] : nullptr;
+}
+
 Province* Map::get_province_by_identifier(std::string const& identifier) {
 	for (Province& province : provinces)
 		if (province.identifier == identifier) return &province;
diff --git a/extension/src/openvic2/Map.hpp b/extension/src/openvic2/Map.hpp
index f3fd1ef..365d78b 100644
--- a/extension/src/openvic2/Map.hpp
+++ b/extension/src/openvic2/Map.hpp
@@ -8,16 +8,20 @@ namespace OpenVic2 {
 
 	struct Province {
 		using colour_t = uint32_t;
+		using index_t = uint16_t;
 		friend struct Map;
 		static const colour_t NULL_COLOUR = 0, MAX_COLOUR = 0xFFFFFF;
+		static const index_t NULL_INDEX = 0, MAX_INDEX = 0xFFFF;
 	private:
+		index_t index;
 		std::string identifier;
 		colour_t colour;
 
-		Province(std::string const& identifier, colour_t colour);
+		Province(index_t index, std::string const& identifier, colour_t colour);
 	public:
 		static std::string colour_to_hex_string(colour_t colour);
 
+		index_t get_index() const;
 		std::string const& get_identifier() const;
 		colour_t get_colour() const;
 		std::string to_string() const;
@@ -26,9 +30,14 @@ namespace OpenVic2 {
 	struct Map {
 	private:
 		std::vector<Province> provinces;
+		bool provinces_locked = false;
 
 	public:
 		bool add_province(std::string const& identifier, Province::colour_t colour, std::string& error_message);
+		void lock_provinces();
+		size_t get_province_count() const;
+
+		Province* get_province_by_index(Province::index_t index);
 		Province* get_province_by_identifier(std::string const& identifier);
 		Province* get_province_by_colour(Province::colour_t colour);
 	};
diff --git a/game/src/GameSession/MapView.gd b/game/src/GameSession/MapView.gd
index 4a44bce..67938f2 100644
--- a/game/src/GameSession/MapView.gd
+++ b/game/src/GameSession/MapView.gd
@@ -11,7 +11,8 @@ const _action_zoomout : StringName = &"map_zoomout"
 const _action_drag : StringName = &"map_drag"
 const _action_click : StringName = &"map_click"
 
-const _shader_param_provinces : StringName = &"province_tex"
+const _shader_param_province_index : StringName = &"province_index_tex"
+const _shader_param_province_colour : StringName = &"province_colour_tex"
 const _shader_param_hover_pos : StringName = &"hover_pos"
 const _shader_param_selected_pos : StringName = &"selected_pos"
 
@@ -34,7 +35,8 @@ const _shader_param_selected_pos : StringName = &"selected_pos"
 @export var _map_mesh_instance : MeshInstance3D
 var _map_mesh : MapMesh
 var _map_shader_material : ShaderMaterial
-var _map_province_shape_image : Image
+var _map_image_size : Vector2
+var _map_province_index_image : Image
 var _map_mesh_corner : Vector2
 var _map_mesh_dims : Vector2
 
@@ -49,17 +51,14 @@ func _ready():
 	if _map_mesh_instance == null:
 		push_error("MapView's _map_mesh variable hasn't been set!")
 		return
-	_map_province_shape_image = MapSingleton.get_province_shape_image()
-	if _map_province_shape_image == null:
-		push_error("Failed to get province shape image!")
-		return
 	if not _map_mesh_instance.mesh is MapMesh:
 		push_error("Invalid map mesh class: ", _map_mesh_instance.mesh.get_class(), "(expected MapMesh)")
 		return
 	_map_mesh = _map_mesh_instance.mesh
 
 	# Set map mesh size and get bounds
-	_map_mesh.aspect_ratio = float(_map_province_shape_image.get_width()) / float(_map_province_shape_image.get_height())
+	_map_image_size = Vector2(Vector2i(MapSingleton.get_width(), MapSingleton.get_height()))
+	_map_mesh.aspect_ratio = _map_image_size.x / _map_image_size.y
 	var map_mesh_aabb := _map_mesh.get_core_aabb() * _map_mesh_instance.transform
 	_map_mesh_corner = Vector2(
 		min(map_mesh_aabb.position.x, map_mesh_aabb.end.x),
@@ -78,18 +77,28 @@ func _ready():
 		push_error("Invalid map mesh material class: ", map_material.get_class())
 		return
 	_map_shader_material = map_material
-	var texture := ImageTexture.create_from_image(_map_province_shape_image)
-	_map_shader_material.set_shader_parameter(_shader_param_provinces, texture)
+	# Province index texture
+	_map_province_index_image = MapSingleton.get_province_index_image()
+	if _map_province_index_image == null:
+		push_error("Failed to get province index image!")
+		return
+	var province_index_texture := ImageTexture.create_from_image(_map_province_index_image)
+	_map_shader_material.set_shader_parameter(_shader_param_province_index, province_index_texture)
+	# Province colour texture
+	var province_colour_image = MapSingleton.get_province_colour_image()
+	if province_colour_image == null:
+		push_error("Failed to get province colour image!")
+		return
+	var province_colour_texture := ImageTexture.create_from_image(province_colour_image)
+	_map_shader_material.set_shader_parameter(_shader_param_province_colour, province_colour_texture)
 
 func _unhandled_input(event : InputEvent):
 	if event.is_action_pressed(_action_click):
 		# Check if the mouse is outside of bounds
-		var mouse_inside_flag := 0 < _mouse_pos_map.x and _mouse_pos_map.x < 1 and 0 < _mouse_pos_map.y and _mouse_pos_map.y < 1
-		if mouse_inside_flag:
-			var mouse_pixel_pos := Vector2i(_mouse_pos_map * Vector2(_map_province_shape_image.get_size()))
-			var province_colour := _map_province_shape_image.get_pixelv(mouse_pixel_pos).to_argb32() & 0xFFFFFF
-			var province_identifier := MapSingleton.get_province_identifier_from_colour(province_colour)
+		if _map_mesh.is_valid_uv_coord(_mouse_pos_map):
 			_map_shader_material.set_shader_parameter(_shader_param_selected_pos, _mouse_pos_map)
+			var mouse_pixel_pos := Vector2i(_mouse_pos_map * _map_image_size)
+			var province_identifier := MapSingleton.get_province_identifier_from_pixel_coords(mouse_pixel_pos)
 			province_selected.emit(province_identifier)
 
 	elif event is InputEventMouseMotion and Input.is_action_pressed(_action_drag):
diff --git a/game/src/GameSession/TerrainMap.gdshader b/game/src/GameSession/TerrainMap.gdshader
index 61b7032..be2bbe1 100644
--- a/game/src/GameSession/TerrainMap.gdshader
+++ b/game/src/GameSession/TerrainMap.gdshader
@@ -3,24 +3,46 @@ shader_type spatial;
 render_mode unshaded;
 
 // Cosmetic terrain texture
-uniform sampler2D terrain_tex: source_color, repeat_enable;
-// Province shape texture
-uniform sampler2D province_tex: source_color, repeat_enable;
+uniform sampler2D terrain_tex: source_color, repeat_enable, filter_linear;
+// Province index texture
+uniform sampler2D province_index_tex : repeat_enable, filter_nearest;
+// Province colour texture
+uniform sampler2D province_colour_tex: source_color, repeat_enable, filter_nearest;
 // Position of the mouse over the map mesh in UV coords
 uniform vec2 hover_pos;
 // Position in UV coords of a pixel belonging to the currently selected province
 uniform vec2 selected_pos;
 
-const vec3 NULL_COLOUR = vec3(0.0);
+uvec2 vec2_to_uvec2(vec2 v) {
+	return uvec2(v * 256.0);
+}
+
+uint uvec2_to_uint(uvec2 v) {
+	return (v.y << 8u) | v.x;
+}
+
+uvec2 read_uvec2(sampler2D tex, vec2 uv) {
+	return vec2_to_uvec2(texture(tex, uv).rg);
+}
+
+uint read_uint16(sampler2D tex, vec2 uv) {
+	return uvec2_to_uint(read_uvec2(tex, uv));
+}
 
 void fragment() {
-	vec3 terrain_colour = texture(terrain_tex, UV).rgb;
-	vec3 prov_colour = texture(province_tex, UV).rgb;
-	vec3 hover_colour = texture(province_tex, hover_pos).rgb;
-	vec3 selected_colour = texture(province_tex, selected_pos).rgb;
+	uvec2 prov_idx_split = read_uvec2(province_index_tex, UV);
+
+	uint prov_index = uvec2_to_uint(prov_idx_split);
+	uint hover_index = read_uint16(province_index_tex, hover_pos);
+	uint selected_index = read_uint16(province_index_tex, selected_pos);
+
 	// Boost prov_colour's contribution if it matches hover_colour or selected_colour
-	float mix_val = float(prov_colour == hover_colour) * 0.3 + float(prov_colour == selected_colour) * 0.5;
-	// Set to 0 if the province has NULL colour
-	mix_val *= 1.0 - float(prov_colour ==  NULL_COLOUR);
-	ALBEDO = mix(terrain_colour, prov_colour, mix_val);
+	float mix_val = float(prov_index == hover_index) * 0.3 + float(prov_index == selected_index) * 0.5;
+	// Don't mix if the province index is 0
+	mix_val *= float(prov_index != 0u);
+
+	vec3 terrain_colour = texture(terrain_tex, UV).rgb;
+	vec3 province_colour = texelFetch(province_colour_tex, ivec2(prov_idx_split), 0).rgb;
+
+	ALBEDO = mix(terrain_colour, province_colour, mix_val);
 }