# Interface definition for thorn AHFinderDirect
# $Header$

implements: AHFinderDirect
inherits: Grid ADMBase StaticConformal SpaceMask IO always

# include file provided by SpaceMask
USES INCLUDE: SpaceMask.h

# provides aliased functions for various other thorns
# FIXME: this really belongs in Erik Schnetter's "generic surface" thorn
# ... returns local coordinate origin for a given horizon
SUBROUTINE HorizonLocalCoordinateOrigin					\
	(CCTK_INT IN horizon_number,					\
	 CCTK_REAL OUT origin_x, CCTK_REAL OUT origin_y, CCTK_REAL OUT origin_z)
# ... computes horizon radius in the direction of each (x,y,z) point,
#     or -1.0 if this horizon wasn't found
# ... more precisely:
#	For each (x,y,z), consider the ray from the local coordinate
#	origin through (x,y,z).  This function computes the Euclidean
#	distance between the local coordinate origin and this ray's
#	intersection with the horizon, or -1.0 if this horizon wasn't
#	found the last time we searched for it.
SUBROUTINE HorizonRadiusInDirection					   \
	(CCTK_INT IN horizon_number,					   \
	 CCTK_INT IN N_points,						   \
	 CCTK_REAL IN ARRAY x, CCTK_REAL IN ARRAY y, CCTK_REAL IN ARRAY z, \
	 CCTK_REAL OUT ARRAY radius)
PROVIDES FUNCTION HorizonLocalCoordinateOrigin				\
	WITH AHFinderDirect_local_coordinate_origin			\
	LANGUAGE C
PROVIDES FUNCTION HorizonRadiusInDirection				\
	WITH AHFinderDirect_radius_in_direction				\
	LANGUAGE C

# uses aliased function maybe provided by DriftCorrect
SUBROUTINE SetDriftCorrectPosition(CCTK_POINTER IN GH, CCTK_REAL IN x,	\
						       CCTK_REAL IN y,	\
						       CCTK_REAL IN z)
USES FUNCTION SetDriftCorrectPosition

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