Merge branch 'master' into jgrpp

# Conflicts:
#	.github/workflows/ci-build.yml
#	src/ai/ai_gui.cpp
#	src/blitter/32bpp_optimized.cpp
#	src/blitter/32bpp_simple.cpp
#	src/blitter/32bpp_sse2.cpp
#	src/blitter/8bpp_optimized.cpp
#	src/blitter/8bpp_simple.cpp
#	src/blitter/null.cpp
#	src/blitter/null.hpp
#	src/company_gui.cpp
#	src/game/game_gui.cpp
#	src/genworld_gui.cpp
#	src/gfx.cpp
#	src/gfx_func.h
#	src/graph_gui.cpp
#	src/industry_gui.cpp
#	src/linkgraph/linkgraphjob.cpp
#	src/network/network_gui.cpp
#	src/newgrf_debug_gui.cpp
#	src/openttd.cpp
#	src/pathfinder/npf/aystar.h
#	src/road_gui.cpp
#	src/saveload/order_sl.cpp
#	src/saveload/saveload.cpp
#	src/saveload/saveload.h
#	src/script/api/script_log.cpp
#	src/script/api/script_town.cpp
#	src/script/script_gui.cpp
#	src/settings.cpp
#	src/settings_gui.cpp
#	src/settings_table.cpp
#	src/settings_type.h
#	src/smallmap_gui.cpp
#	src/sortlist_type.h
#	src/spritecache.cpp
#	src/spriteloader/grf.cpp
#	src/spriteloader/grf.hpp
#	src/spriteloader/spriteloader.hpp
#	src/station_cmd.cpp
#	src/station_cmd.h
#	src/station_gui.cpp
#	src/strings.cpp
#	src/toolbar_gui.cpp
#	src/town_cmd.cpp
#	src/town_gui.cpp
#	src/vehicle_gui.cpp
#	src/vehicle_gui_base.h
#	src/video/opengl.cpp
#	src/video/opengl.h
#	src/widgets/dropdown.cpp
#	src/widgets/dropdown_type.h
#	src/window_gui.h

src/spriteloader/spriteloader.hpp

@@ -65,6 +65,11 @@ public:
 		static ReusableBuffer<SpriteLoader::CommonPixel> buffer[ZOOM_LVL_SPR_COUNT];
 	};
 
+	/**
+	 * Type defining a collection of sprites, one for each zoom level.
+	 */
+	using SpriteCollection = std::array<Sprite, ZOOM_LVL_SPR_COUNT>;
+
 	/**
 	 * Load a sprite from the disk and return a sprite struct which is the same for all loaders.
 	 * @param[out] sprite The sprites to fill with data.
@@ -75,7 +80,7 @@ public:
 	 * @param control_flags Control flags, see SpriteCacheCtrlFlags.
 	 * @return Bit mask of the zoom levels successfully loaded or 0 if no sprite could be loaded.
 	 */
-	virtual uint8 LoadSprite(SpriteLoader::Sprite *sprite, SpriteFile &file, size_t file_pos, SpriteType sprite_type, bool load_32bpp, uint count, uint16 control_flags, uint8 zoom_levels) = 0;
+	virtual uint8 LoadSprite(SpriteLoader::SpriteCollection &sprite, SpriteFile &file, size_t file_pos, SpriteType sprite_type, bool load_32bpp, uint count, uint16 control_flags, uint8 zoom_levels) = 0;
 
 	virtual ~SpriteLoader() = default;
 };
@@ -127,7 +132,7 @@ public:
 	/**
 	 * Convert a sprite from the loader to our own format.
 	 */
-	virtual Sprite *Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator) = 0;
+	virtual Sprite *Encode(const SpriteLoader::SpriteCollection &sprite, AllocatorProc *allocator) = 0;
 
 	/**
 	 * Get the value which the height and width on a sprite have to be aligned by.