# HG changeset patch
# Parent 1c0964d1d047cbae76eb84112815a8fa8fd7e740

diff --git a/src/map.h b/src/map.h
--- a/src/map.h
+++ b/src/map.h
@@ -16,7 +16,6 @@
 #include "path.h"
 #include "geometry.h"
 #include "sprite_store.h"
-#include "bitmath.h"
 
 #include <map>
 
@@ -360,17 +359,6 @@ public:
 };
 
 /**
- * Does the instance data indicate a valid path (that is, a voxel with an actual path tile)?
- * @param instance_data Instance data to examine.
- * @return Whether the instance data indicates a valid path.
- * @pre The instance must be #SRI_PATH
- */
-static inline bool HasValidPath(uint16 instance_data)
-{
-	return instance_data != PATH_INVALID;
-}
-
-/**
  * Does the given voxel contain a valid path?
  * @param v %Voxel to examine.
  * @return @c true if the voxel contains a valid path, else \c false.
@@ -382,30 +370,6 @@ static inline bool HasValidPath(const Vo
 }
 
 /**
- * Extract the imploded path slope from the instance data.
- * @param instance_data Instance data to examine.
- * @return Imploded slope of the path.
- * @pre instance data must be a valid path.
- */
-static inline PathSprites GetImplodedPathSlope(uint16 instance_data)
-{
-	return (PathSprites)GB(instance_data, 0, 6);
-}
-
-/**
- * Change the path slope in the path instance data.
- * @param instance_data Previous instance data.
- * @param slope New imploded path slope.
- * @return New instance data of a path.
- * @pre instance data must be a valid path.
- */
-static inline uint16 SetImplodedPathSlope(uint16 instance_data, uint8 slope)
-{
-	SB(instance_data, 0, 6, slope);
-	return instance_data;
-}
-
-/**
  * Get the slope of the path (imploded value).
  * @param v %Voxel to examine.
  * @return Imploded slope of the path.
@@ -420,28 +384,6 @@ static inline PathSprites GetImplodedPat
 	return ps;
 }
 
-/**
- * Get the path type from the path voxel instance data.
- * @param instance_data Instance data to examine.
- * @return Type of path.
- * @pre instance data must be a valid path.
- */
-static inline PathType GetPathType(uint16 instance_data)
-{
-	return (PathType)GB(instance_data, 6, 2);
-}
-
-/**
- * Construct instance data for a valid path.
- * @param slope Imploded slope of the path.
- * @param path_type Type of the path.
- * @return Instance data of a valid path.
- */
-static inline uint16 MakePathInstanceData(uint8 slope, PathType path_type)
-{
-	return slope | (path_type << 6);
-}
-
 /** Possible ownerships of a tile. */
 enum TileOwner {
 	OWN_NONE,     ///< Tile not owned by the park and not for sale.
diff --git a/src/path.cpp b/src/path.cpp
--- a/src/path.cpp
+++ b/src/path.cpp
@@ -240,6 +240,17 @@ uint8 GetPathExits(const Voxel *v)
 }
 
 /**
+ * If the path instance data has decoration, would it be visible?
+ * @param instance_data Instance data to examine.
+ * @return Path decoration is or could be visible.
+ */
+bool IsPathDecorationVisible(uint16 instance_data)
+{
+	uint8 exp_slope = _path_expand[GetImplodedPathSlope(instance_data)];
+	return (exp_slope & PATHMASK_EDGES) != PATHMASK_EDGES;
+}
+
+/**
  * Walk over a queue path from the given entry edge at the given position.
  * If it leads to a new voxel edge, the provided position and edge is update with the exit point.
  * @param voxel_pos [inout] Start voxel position before the queue path, updated to last voxel position.
diff --git a/src/path.h b/src/path.h
--- a/src/path.h
+++ b/src/path.h
@@ -7,12 +7,23 @@
  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with FreeRCT. If not, see <http://www.gnu.org/licenses/>.
  */
 
-/** @file path.h %Path definitions. */
+/**
+ * @file path.h %Path definitions.
+ *
+ * Path instance data has the following structure:
+ * - bit 0..5 Imploded slope of the path. @see HasValidPath, GetImplodedPathSlope, SetImplodedPathSlope
+ * - bit 6..7 Path type. @see GetPathType
+ * - bit 8..11 Amount of litter. If no litter bin or demolished litter bin, values above 3 count as 3, and are lying on the path itself.
+ * - bit 12 Unused.
+ * - bit 13..14 Path decoration (litter bin, benches, or lamp posts. @see PathDecoration
+ * - bit 15 Path decoration has been demolished. Only valid if the decoration is visible to the user.
+ */
 
 #ifndef PATH_H
 #define PATH_H
 
 #include "tile.h"
+#include "bitmath.h"
 
 /**
  * Available path sprites.
@@ -118,6 +129,168 @@ enum PathStatus {
 	PAS_QUEUE_PATH,  ///< %Path to queue on.
 };
 
+/** Path decoration. */
+enum PathDecoration {
+	PDEC_NONE,      ///< Path has no decoration.
+	PDEC_LITTERBIN, ///< Path has litter bins.
+	PDEC_BENCH,     ///< Path has benches.
+	PDEC_LAMPPOST,  ///< Path has lamp posts.
+};
+
+/**
+ * Does the instance data indicate a valid path (that is, a voxel with an actual path tile)?
+ * @param instance_data Instance data to examine.
+ * @return Whether the instance data indicates a valid path.
+ * @pre The instance must be #SRI_PATH
+ */
+static inline bool HasValidPath(uint16 instance_data)
+{
+	return GB(instance_data, 0, 6) != PATH_INVALID;
+}
+
+/**
+ * Extract the imploded path slope from the instance data.
+ * @param instance_data Instance data to examine.
+ * @return Imploded slope of the path.
+ * @pre instance data must be a valid path.
+ */
+static inline PathSprites GetImplodedPathSlope(uint16 instance_data)
+{
+	return (PathSprites)GB(instance_data, 0, 6);
+}
+
+/**
+ * Change the path slope in the path instance data.
+ * @param instance_data Previous instance data.
+ * @param slope New imploded path slope.
+ * @return New instance data of a path.
+ * @pre instance data must be a valid path.
+ */
+static inline uint16 SetImplodedPathSlope(uint16 instance_data, uint8 slope)
+{
+	SB(instance_data, 0, 6, slope);
+	return instance_data;
+}
+
+/**
+ * Get the path type from the path voxel instance data.
+ * @param instance_data Instance data to examine.
+ * @return Type of path.
+ * @pre instance data must be a valid path.
+ */
+static inline PathType GetPathType(uint16 instance_data)
+{
+	return (PathType)GB(instance_data, 6, 2);
+}
+
+/**
+ * Get the decoration of path instance data.
+ * @param instance_data Instance data to examine.
+ * @return The decoration of the path.
+ * @pre instance data must be a valid path, decoration must be visible to the user.
+ */
+static inline PathDecoration GetPathDecoration(uint16 instance_data)
+{
+	return (PathDecoration)GB(instance_data, 13, 2);
+}
+
+/**
+ * Set the decoration of the path.
+ * @param instance_data Instance data to update.
+ * @param decoration Path decoration to set.
+ * @return Modified instance data.
+ * @pre instance data must be a valid path, decoration must be visible to the user.
+ */
+static inline uint16 SetPathDecoration(uint16 instance_data, PathDecoration decoration)
+{
+	SB(instance_data, 13, 2, decoration);
+	return instance_data;
+}
+
+/**
+ * Get the 'demolished' bit of path instance data.
+ * @param instance_data Instance data to examine.
+ * @return The 'demolished' bit of the path.
+ * @pre instance data must be a valid path, decoration must be visible to the user.
+ */
+static inline bool GetPathDemolished(uint16 instance_data)
+{
+	return GB(instance_data, 15, 1) != 0;
+}
+
+/**
+ * Set the 'demolished' bit of path instance data.
+ * @param instance_data Instance data to update.
+ * @param demolished New state of the 'demolished' bit of the path.
+ * @return Modified instance data.
+ * @pre instance data must be a valid path, decoration must be visible to the user.
+ */
+static inline uint16 SetPathDemolished(uint16 instance_data, bool demolished)
+{
+	SB(instance_data, 15, 1, demolished);
+	return instance_data;
+}
+
+bool IsPathDecorationVisible(uint16 instance_data);
+
+/**
+ * Is the path instance_data demolished, and is it visible to the user?
+ * @param instance_data Instance data to examine.
+ * @return Demolished state of the path, as observable by the user.
+ */
+static inline bool GetVisiblePathDemolished(uint16 instance_data)
+{
+	if (!IsPathDecorationVisible(instance_data)) return false;
+	return GetPathDemolished(instance_data);
+}
+
+/**
+ * Get the litter data from the path instance data.
+ * @param instance_data Instance data to examine.
+ * @return Value of the litter data in the path.
+ */
+static inline uint GetPathLitter(uint16 instance_data)
+{
+	return GB(instance_data, 8, 4);
+}
+
+/**
+ * Set the litter data in the path instance data.
+ * @param instance_data Previous instance data.
+ * @param litter New value for the litter data.
+ * @return New instance data of a path.
+ */
+static inline uint16 SetPathLitter(uint16 instance_data, uint litter)
+{
+	SB(instance_data, 8, 4, std::min(0xFu, litter));
+	return instance_data;
+}
+
+/**
+ * How much litter is visible to the user (on the path).
+ * @param instance_data Instance data to examine.
+ * @return Amount of visible litter on the path.
+ */
+static inline uint GetVisiblePathLitter(uint16 instance_data)
+{
+	int litter = GetPathLitter(instance_data);
+	if (GetPathDecoration(instance_data) == PDEC_LITTERBIN && !GetPathDemolished(instance_data)) {
+		return std::max(0, litter - 12);
+	}
+	return std::min(3, litter);
+}
+
+/**
+ * Construct instance data for a valid path without litter, path decorations, and not demolished.
+ * @param slope Imploded slope of the path.
+ * @param path_type Type of the path.
+ * @return Instance data of a valid path.
+ */
+static inline uint16 MakePathInstanceData(uint8 slope, PathType path_type)
+{
+	return slope | (path_type << 6);
+}
+
 extern const PathSprites _path_up_from_edge[EDGE_COUNT];
 extern const PathSprites _path_down_from_edge[EDGE_COUNT];
 extern const uint8 _path_expand[];