* ImageIndex typedef moved from ImageId.hpp to new file ImageIndexType.h.
* SPR_NONE redefined as ImageIndex type in ImageIndexType.h.
* SPR_NONE renamed to kSpriteIdNull
* Remove casts and enum all sprites as ImageIndex
* Remove sprites.h include from LandTool.h, RideData.h
* Ensure all RTD headers include sprites.h
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Co-authored-by: Aaron van Geffen <aaron@aaronweb.net>
* Introduce isToolActive function
* Ride window: use isToolActive instead of gCurrentToolWidget
* Footpath window: use isToolActive instead of gCurrentToolWidget
* Staff window: use isToolActive instead of gCurrentToolWidget
* MazeConstruction window: use isToolActive instead of gCurrentToolWidget
* Guest window: use isToolActive instead of gCurrentToolWidget
* Map window: use isToolActive instead of gCurrentToolWidget
* LandRights window: use isToolActive instead of gCurrentToolWidget
* Replace SceneryToolIsActive legacy function with calls to isToolActive
* ClearScenery window: use isToolActive instead of gCurrentToolWidget
* Scenery window: use isToolActive instead of gCurrentToolWidget
* Water window: use isToolActive instead of gCurrentToolWidget
* Land window: use isToolActive instead of gCurrentToolWidget
* Widget: replace WidgetIsActiveTool with isToolActive
* RideConstruction window: use isToolActive instead of gCurrentToolWidget
* Ride: use isToolActive instead of gCurrentToolWidget
* TrackDesignPlace window: use isToolActive instead of gCurrentToolWidget
* StaffList window: use isToolActive instead of gCurrentToolWidget
* ViewClipping window: use isToolActive instead of gCurrentToolWidget
* PatrolArea window: use isToolActive instead of gCurrentToolWidget
* TileInspector window: use isToolActive instead of gCurrentToolWidget
* Park window: use isToolActive instead of gCurrentToolWidget
* Put all of TitleSequenceManager into the same namespace
* Move RideConstructionState into the OpenRCT2 namespace
* Adopt existing namespaces into OpenRCT2 namespace
This adds `using namespace OpenRCT2` to compilation units where appropriate,
as a means to get the codebase to compile until these units have been placed
in a namespace of their own.
