(svn r20126) -Fix [FS#3883]: Make railtype Terrain Type variable aware of RAIL_GROUND_HALF_SNOW. That is, resolve the sprites for upper and lower part of the foundation independently.

src/newgrf_spritegroup.h

@@ -343,6 +343,7 @@ struct ResolverObject {
 		} generic;
 		struct {
 			TileIndex tile;
+			bool upper_halftile;           ///< Are we resolving sprites for the upper halftile?
 		} routes;
 		struct {
 			const struct Station *st;