start rivers

src/openvic-simulation/dataloader/Dataloader.cpp

@@ -602,7 +602,8 @@ bool Dataloader::_load_map_dir(GameManager& game_manager) const {
 
 	if (!map.load_map_images(
 		lookup_file(append_string_views(map_directory, provinces)),
-		lookup_file(append_string_views(map_directory, terrain)), false
+		lookup_file(append_string_views(map_directory, terrain)),
+		lookup_file(append_string_views(map_directory, rivers)), false
 	)) {
 		Logger::error("Failed to load map images!");
 		ret = false;

src/openvic-simulation/map/Map.cpp

@@ -439,7 +439,7 @@ static constexpr colour_t colour_at(uint8_t const* colour_data, int32_t idx) {
 	return (colour_data[idx + 2] << 16) | (colour_data[idx + 1] << 8) | colour_data[idx];
 }
 
-bool Map::load_map_images(fs::path const& province_path, fs::path const& terrain_path, bool detailed_errors) {
+bool Map::load_map_images(fs::path const& province_path, fs::path const& terrain_path, fs::path const& river_path, bool detailed_errors) {
 	if (!provinces.is_locked()) {
 		Logger::error("Province index image cannot be generated until after provinces are locked!");
 		return false;
@@ -476,10 +476,29 @@ bool Map::load_map_images(fs::path const& province_path, fs::path const& terrain
 		return false;
 	}
 
-	if (province_bmp.get_width() != terrain_bmp.get_width() || province_bmp.get_height() != terrain_bmp.get_height()) {
+	BMP river_bmp;
+	if (!(river_bmp.open(river_path) && river_bmp.read_header() && river_bmp.read_palette() && river_bmp.read_pixel_data())) {
+		Logger::error("Failed to read BMP for compatibility mode river image: ", river_path);
+		return false;
+	}
+	static constexpr uint16_t expected_river_bpp = 8;
+	if (river_bmp.get_bits_per_pixel() != expected_river_bpp) {
+		Logger::error(
+			"Invalid river BMP bits per pixel: ", river_bmp.get_bits_per_pixel(), " (expected ", expected_river_bpp, ")"
+		);
+		return false;
+	}
+
+	if (
+		province_bmp.get_width() != terrain_bmp.get_width() ||
+		province_bmp.get_height() != terrain_bmp.get_height() ||
+		province_bmp.get_width() != river_bmp.get_width() ||
+		province_bmp.get_height() != river_bmp.get_height()
+	) {
 		Logger::error(
-			"Mismatched province and terrain BMP dims: ", province_bmp.get_width(), "x", province_bmp.get_height(), " vs ",
-			terrain_bmp.get_width(), "x", terrain_bmp.get_height()
+			"Mismatched map BMP dims: expected ", province_bmp.get_width(), "x", province_bmp.get_height(), " (provinces) got ",
+			terrain_bmp.get_width(), "x", terrain_bmp.get_height(), " (terrain) and ", river_bmp.get_width(), "x",
+			river_bmp.get_height(), " (rivers)"
 		);
 		return false;
 	}
@@ -490,6 +509,7 @@ bool Map::load_map_images(fs::path const& province_path, fs::path const& terrain
 
 	uint8_t const* province_data = province_bmp.get_pixel_data().data();
 	uint8_t const* terrain_data = terrain_bmp.get_pixel_data().data();
+	uint8_t const* river_data = river_bmp.get_pixel_data().data();
 
 	std::vector<bool> province_checklist(provinces.size());
 	std::vector<fixed_point_map_t<TerrainType const*>> terrain_type_pixels_list(provinces.size());
@@ -570,6 +590,14 @@ bool Map::load_map_images(fs::path const& province_path, fs::path const& terrain
 		Logger::warning("Province image is missing ", missing, " province colours");
 	}
 
+	// load river bitmap
+	for (size_t y = 0; y < height; ++y) {
+		for (size_t x = 0; x < width; ++x) {
+			const size_t idx = x + y * width;
+			// TODO: load river crossing into provinces, river crossing is present if direct line from province centre (positions.txt) to adjacent province centre crosses river
+		}
+	}
+
 	return ret;
 }
 

src/openvic-simulation/map/Map.hpp

@@ -122,7 +122,7 @@ namespace OpenVic {
 		bool load_province_definitions(std::vector<ovdl::csv::LineObject> const& lines);
 		bool load_province_positions(BuildingTypeManager const& building_type_manager, ast::NodeCPtr root);
 		bool load_region_file(ast::NodeCPtr root);
-		bool load_map_images(fs::path const& province_path, fs::path const& terrain_path, bool detailed_errors);
+		bool load_map_images(fs::path const& province_path, fs::path const& terrain_path, fs::path const& river_path, bool detailed_errors);
 		bool generate_and_load_province_adjacencies(std::vector<ovdl::csv::LineObject> const& additional_adjacencies);
 	};
 }