Invalidate the Picture cache when a picture is written to the disk

Otherwise an old version of the Picture will be loaded next time ShowPicture is used

Author: Ghabry

src/cache.cpp

@@ -248,6 +248,7 @@ namespace {
 		BitmapRef bmp;
 
 		const auto key = MakeHashKey(s.directory, filename, transparent, extra_flags);
+
 		auto it = cache.find(key);
 		if (it == cache.end()) {
 			if (filename == CACHE_DEFAULT_BITMAP) {
@@ -529,6 +530,16 @@ BitmapRef Cache::SpriteEffect(const BitmapRef& src_bitmap, const Rect& rect, boo
 	} else { return it->second.lock(); }
 }
 
+void Cache::Invalidate(std::string_view section) {
+	for (auto it = cache.begin(); it != cache.end(); ) {
+		if (StartsWith(it->first, section)) {
+			it = cache.erase(it);
+		} else {
+			++it;
+		}
+	}
+}
+
 void Cache::Clear() {
 	cache_effects.clear();
 	cache.clear();

src/cache.h

@@ -58,6 +58,12 @@ namespace Cache {
 	BitmapRef Tile(std::string_view filename, int tile_id);
 	BitmapRef SpriteEffect(const BitmapRef& src_bitmap, const Rect& rect, bool flip_x, bool flip_y, const Tone& tone, const Color& blend);
 
+	/**
+	 * Removes all cached entries of the given section
+	 *
+	 * @param section Cache section to remove
+	 */
+	void Invalidate(std::string_view section);
 	void Clear();
 	void ClearAll();
 

src/game_interpreter.cpp

@@ -5543,6 +5543,8 @@ bool Game_Interpreter::CommandManiacWritePicture(lcf::rpg::EventCommand const& c
 		auto img_out = FileFinder::OpenWrite(filename);
 		if (img_out) {
 			bitmap->WritePNG(img_out);
+			// Not ideal but figuring out the exact cache entry is complicated
+			Cache::Invalidate("Picture");
 		} else {
 			Output::Warning("ManiacSaveImage: Failed to open file for writing: {}", filename);
 		}