--- a/src/slope.h Mon Jul 23 16:15:40 2007 +0000
+++ b/src/slope.h Mon Jul 23 16:30:59 2007 +0000
@@ -1,39 +1,67 @@
/* $Id$ */
-/** @file slope.h */
+/** @file slope.h Definitions of a slope.
+ * This file defines the enumeration and helper functions for handling
+ * the slope info of a tile.
+ */
#ifndef SLOPE_H
#define SLOPE_H
+/**
+ * Enumeration for the slope-type.
+ *
+ * This enumeration use the chars N,E,S,W corresponding the
+ * direction north, east, south and west. The top corner of a tile
+ * is the north-part of the tile. The whole slope is encoded with
+ * 5 bits, 4 bits for each corner and 1 bit for a steep-flag.
+ */
enum Slope {
- SLOPE_FLAT = 0x00,
- SLOPE_W = 0x01,
- SLOPE_S = 0x02,
- SLOPE_E = 0x04,
- SLOPE_N = 0x08,
- SLOPE_STEEP = 0x10,
- SLOPE_NW = SLOPE_N | SLOPE_W,
- SLOPE_SW = SLOPE_S | SLOPE_W,
- SLOPE_SE = SLOPE_S | SLOPE_E,
- SLOPE_NE = SLOPE_N | SLOPE_E,
- SLOPE_EW = SLOPE_E | SLOPE_W,
- SLOPE_NS = SLOPE_N | SLOPE_S,
- SLOPE_ELEVATED = SLOPE_N | SLOPE_E | SLOPE_S | SLOPE_W,
- SLOPE_NWS = SLOPE_N | SLOPE_W | SLOPE_S,
- SLOPE_WSE = SLOPE_W | SLOPE_S | SLOPE_E,
- SLOPE_SEN = SLOPE_S | SLOPE_E | SLOPE_N,
- SLOPE_ENW = SLOPE_E | SLOPE_N | SLOPE_W,
- SLOPE_STEEP_W = SLOPE_STEEP | SLOPE_NWS,
- SLOPE_STEEP_S = SLOPE_STEEP | SLOPE_WSE,
- SLOPE_STEEP_E = SLOPE_STEEP | SLOPE_SEN,
- SLOPE_STEEP_N = SLOPE_STEEP | SLOPE_ENW
+ SLOPE_FLAT = 0x00, ///< a flat tile
+ SLOPE_W = 0x01, ///< the west corner of the tile is raised
+ SLOPE_S = 0x02, ///< the south corner of the tile is raised
+ SLOPE_E = 0x04, ///< the east corner of the tile is raised
+ SLOPE_N = 0x08, ///< the north corner of the tile is raised
+ SLOPE_STEEP = 0x10, ///< indicates the slope is steep
+ SLOPE_NW = SLOPE_N | SLOPE_W, ///< north and west corner are raised
+ SLOPE_SW = SLOPE_S | SLOPE_W, ///< south and west corner are raised
+ SLOPE_SE = SLOPE_S | SLOPE_E, ///< south and east corner are raised
+ SLOPE_NE = SLOPE_N | SLOPE_E, ///< north and east corner are raised
+ SLOPE_EW = SLOPE_E | SLOPE_W, ///< east and west corner are raised
+ SLOPE_NS = SLOPE_N | SLOPE_S, ///< north and south corner are raised
+ SLOPE_ELEVATED = SLOPE_N | SLOPE_E | SLOPE_S | SLOPE_W, ///< all corner are raised, similar to SLOPE_FLAT
+ SLOPE_NWS = SLOPE_N | SLOPE_W | SLOPE_S, ///< north, west and south corner are raised
+ SLOPE_WSE = SLOPE_W | SLOPE_S | SLOPE_E, ///< west, south and east corner are raised
+ SLOPE_SEN = SLOPE_S | SLOPE_E | SLOPE_N, ///< south, east and north corner are raised
+ SLOPE_ENW = SLOPE_E | SLOPE_N | SLOPE_W, ///< east, north and west corner are raised
+ SLOPE_STEEP_W = SLOPE_STEEP | SLOPE_NWS, ///< a steep slope falling to east (from west)
+ SLOPE_STEEP_S = SLOPE_STEEP | SLOPE_WSE, ///< a steep slope falling to north (from south)
+ SLOPE_STEEP_E = SLOPE_STEEP | SLOPE_SEN, ///< a steep slope falling to west (from east)
+ SLOPE_STEEP_N = SLOPE_STEEP | SLOPE_ENW ///< a steep slope falling to south (from north)
};
+/**
+ * Checks if a slope is steep.
+ *
+ * @param s The given #Slope.
+ * @return True if the slope is steep, else false.
+ */
static inline bool IsSteepSlope(Slope s)
{
return (s & SLOPE_STEEP) != 0;
}
+/**
+ * Return the complement of a slope.
+ *
+ * This method returns the complement of a slope. The complement of a
+ * slope is a slope with raised corner which aren't raised in the given
+ * slope.
+ *
+ * @pre The slope must not be steep.
+ * @param s The #Slope to get the complement.
+ * @return a complement Slope of the given slope.
+ */
static inline Slope ComplementSlope(Slope s)
{
assert(!IsSteepSlope(s));