NML:List of tile slopes

Tiles in TTD can have various slopes. The slope is a bitmask that may contain the following bits:

bit flag	meaning
CORNER_W	west corner is above the lowest corner.
CORNER_S	south corner is above the lowest corner.
CORNER_E	east corner is above the lowest corner.
CORNER_N	north corner is above the lowest corner.
IS_STEEP_SLOPE	this tile is a steep slope (the corner opposite to the lowest corner is 2 units higher).

The resulting, possible values of this bitmask are given in the following table. The image below that illustrates them graphically. See also the builtin function num_corners_raised(slope).

Sprites for slopes are always in the same order in TTD. For example, GROUND_SPRITE_NORMAL is the sprite number of a flat grass tile. It is followed by 18 other sprites, that display a flat grass tile for each possible slope. The order of these sprites is given in the last column of the table. The builtin function slope_to_sprite_offset(slope) can be used to determine the sprite offset of a given slope.

Named constant	Equivalent bitmask	Numerical value	Sprite offset
SLOPE_FLAT	bitmask()	0	0
SLOPE_W	bitmask(CORNER_W)	1	1
SLOPE_S	bitmask(CORNER_S)	2	2
SLOPE_E	bitmask(CORNER_E)	4	4
SLOPE_N	bitmask(CORNER_N)	8	8
SLOPE_NW	bitmask(CORNER_N, CORNER_W)	9	9
SLOPE_SW	bitmask(CORNER_S, CORNER_W)	3	3
SLOPE_SE	bitmask(CORNER_S, CORNER_E)	6	6
SLOPE_NE	bitmask(CORNER_N, CORNER_E)	12	12
SLOPE_EW	bitmask(CORNER_E, CORNER_W)	5	5
SLOPE_NS	bitmask(CORNER_N, CORNER_S)	10	10
SLOPE_NWS	bitmask(CORNER_N, CORNER_W, CORNER_S)	11	11
SLOPE_WSE	bitmask(CORNER_W, CORNER_S, CORNER_E)	7	7
SLOPE_SEN	bitmask(CORNER_S, CORNER_E, CORNER_N)	14	14
SLOPE_ENW	bitmask(CORNER_E, CORNER_N, CORNER_W)	13	13
SLOPE_STEEP_W	bitmask(CORNER_N, CORNER_W, CORNER_S, IS_STEEP_SLOPE)	27	17
SLOPE_STEEP_S	bitmask(CORNER_W, CORNER_S, CORNER_E, IS_STEEP_SLOPE)	23	16
SLOPE_STEEP_E	bitmask(CORNER_S, CORNER_E, CORNER_N, IS_STEEP_SLOPE)	30	18
SLOPE_STEEP_N	bitmask(CORNER_E, CORNER_N, CORNER_W, IS_STEEP_SLOPE)	29	15

tile slopes