surface Class Reference
[surfaces]

Base class for all ACIS surface types, which defines the basic virtual functions that are supplied for all specific surface classes. More...

#include <surdef.hxx>

Inheritance diagram for surface:

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Collaboration diagram for surface:

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List of all members.

Public Member Functions

virtual int accurate_derivs (const SPApar_box &box=*(SPApar_box *) NULL_REF) const

Returns the number of derivatives of this surface that can be found accurately and relatively directly.

virtual const double * all_discontinuities_u (int &n_discont, int order)

Returns the number and parameter values of all discontinuities in u of this surface, up to the given order (maximum three).

virtual const double * all_discontinuities_v (int &n_discont, int order)

Returns the number and parameter values of all discontinuities in v of this surface, up to the given order (maximum three).

virtual SPAbox bound (const SPAbox &box, const SPAtransf &transf=*(SPAtransf *) NULL_REF) const

Returns an object-space box bounding this surface.

virtual SPAbox bound (const SPApar_box &parbox=*(SPApar_box *) NULL_REF, const SPAtransf &transf=*(SPAtransf *) NULL_REF) const

Returns an object-space box bounding this surface.

virtual void change_event ()

Notifies the derived type that this surface has been changed.

virtual check_status_list * check (const check_fix &input=*(const check_fix *) NULL_REF, check_fix &result=*(check_fix *) NULL_REF, const check_status_list *chks=(const check_status_list *) NULL_REF)

Checks for any data errors in this surface, and corrects the errors if possible.

virtual logical closed_u () const

Determines whether this surface is closed, smoothly or not, in the u-parameter direction.

virtual logical closed_v () const

Determines whether this surface is closed, smoothly or not, in the v-parameter direction.

surface * copy_surf () const

Makes a copy of this surface.

virtual void debug (const char *title, FILE *fp=debug_file_ptr) const =0

Prints out a title line and details about this surface to the debug file or any other specified file.

virtual surface * deep_copy (pointer_map *pm=NULL) const =0

Creates a copy of this object that does not share any data with the original.

virtual const double * discontinuities_u (int &n_discont, int order) const

Returns the number and parameter values of discontinuities in u of this surface, of the given order (maximum three), in a read-only array.

virtual const double * discontinuities_v (int &n_discont, int order) const

Returns the number and parameter values of discontinuities in v of this surface, of the given order (maximum three), in a read-only array.

virtual int discontinuous_at_u (double u) const

Determines whether a particular value of u represents a discontinuity of this surface.

virtual int discontinuous_at_v (double v) const

Determines whether a particular value of v represents a discontinuity of this surface.

virtual void eval (const SPApar_pos &param, SPAposition &pos, SPAvector *first_derivs=NULL, SPAvector *second_derivs=NULL) const

Finds the position on a parametric surface corresponding to the given parameter values, and optionally the first and second derivatives as well.

virtual double eval_cross (const SPApar_pos &pos, const SPAunit_vector &normal) const

Finds the curvature of a cross-sectional curve of the parametric surface at the point with the given parameter position.

virtual SPAunit_vector eval_normal (const SPApar_pos &pos) const

Finds the normal to a parametric surface at the point with the given parameter position.

virtual SPAunit_vector eval_outdir (const SPApar_pos &pos) const

Finds the outward direction from this surface at the point with the given parameter position.

virtual SPAposition eval_position (const SPApar_pos &pos) const

Finds the point on a parametric surface with the given parameter position.

surf_princurv eval_prin_curv (const SPApar_pos &pos) const

Finds the principal axes of curvature of this surface at the point with the given parameter position and the curvatures in those directions, in a structure defined for the purpose.

virtual void eval_prin_curv (const SPApar_pos &pos, SPAunit_vector &axis1, double &cur1, SPAunit_vector &axis2, double &cur2) const

Finds the principal axes of curvature of this surface at the point with the given parameter position, and the curvatures in those directions.

virtual int evaluate (const SPApar_pos &param, SPAposition &pos, SPAvector **derivs=NULL, int nd=0, evaluate_surface_quadrant quad=evaluate_surface_unknown) const

Calculates derivatives, of any order up to the number requested, and stores them in vectors provided by the user.

virtual int evaluate_iter (const SPApar_pos &param, surface_evaldata *data, SPAposition &pos, SPAvector **derivs=NULL, int nd=0, evaluate_surface_quadrant quad=evaluate_surface_unknown) const

Calculates derivatives, of any order up to the number requested, in an iterative fashion.

virtual const discontinuity_info & get_disc_info_u () const

Returns read-only access to a discontinuity_info object, if there is one, detailing discontinuities in u.

virtual const discontinuity_info & get_disc_info_v () const

Returns read-only access to a discontinuity_info object, if there is one, detailing discontinuities in v.

virtual curve * get_path () const

Returns the sweep path curve for this surface.

virtual sweep_path_type get_path_type () const

Returns the sweep path type for this surface.

virtual curve * get_profile (double param) const

Returns the sweep profile on this surface.

virtual law * get_rail () const

Returns the rail law for this swept surface.

virtual logical left_handed_uv () const

Indicates whether the parameter coordinate system of this surface is right-handed or left-handed.

void limit (const SPApar_box &box)

Subsets this surface in place, according to the given parameter box.

void limit_u (const SPAinterval &range)

Subsets this surface in place, according to the given interval in u.

void limit_v (const SPAinterval &range)

Subsets this surface in place, according to the given interval in v.

virtual surface * make_copy () const =0

Makes a copy of this surface on the heap, and returns a pointer to it.

virtual surface_evaldata * make_evaldata () const

Constructs a data object to retain evaluation information across calls to evaluate_iter.

virtual logical need_save_as_approx (int save_to_version, logical check_progenitors) const

Queries whether the object needs to be saved to an old version as an approximation.

virtual surface & negate ()=0

Reverses the sense of this surface.

virtual surf_normcone normal_cone (const SPApar_box &parbox, logical approx_OK=FALSE, const SPAtransf &transf=*(SPAtransf *) NULL_REF) const

Returns a cone bounding the normal direction of this surface.

logical operator!= (const surface &surf) const

Tests this surface for inequality to another surface.

virtual surface & operator*= (const SPAtransf &transf)=0

Transforms this surface by the given transformation.

virtual logical operator== (const surface &surf) const

Tests this surface for equality to another surface.

virtual SPApar_pos param (const SPAposition &pos, const SPApar_pos &guess=*(SPApar_pos *) NULL_REF) const

Finds the parameter position of a given point on this surface, given an optional first guess.

SPApar_dir param_dir (const SPAunit_vector &dir, const SPApar_pos &pos) const

Finds the direction in parameter space of a given object-space direction on this surface, at a given parameter position.

virtual double param_period_u () const

Returns the period, in u, of a periodic parametric surface.

virtual double param_period_v () const

Returns the period, in v, of a periodic parametric surface.

virtual SPApar_box param_range (const SPAbox &box=*(SPAbox *) NULL_REF) const

Returns the principal parameter range of this surface.

virtual SPAinterval param_range_u (const SPAbox &box=*(SPAbox *) NULL_REF) const

Returns the principal parameter range of a surface in the u-parameter direction.

virtual SPAinterval param_range_v (const SPAbox &box=*(SPAbox *) NULL_REF) const

Returns the principal parameter range of a surface in the v-parameter direction.

virtual SPApar_vec param_unitvec (const SPAunit_vector &dir, const SPApar_pos &pos) const

Finds the rate of change in the surface parameter corresponding to a unit velocity in a given object-space direction, at a given position in parameter space.

virtual logical parametric () const

Returns TRUE if this surface is a parametric surface - otherwise returns FALSE.

virtual logical periodic_u () const

Determines if this surface is periodic in the u-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).

virtual logical periodic_v () const

Determines if this surface is periodic in the v-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).

virtual logical planar (SPAposition &pos, SPAunit_vector &normal) const

Reports whether this surface is planar.

virtual double point_cross (const SPAposition &pos, const SPAunit_vector &normal, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF) const

Finds the curvature of a cross-sectional curve of this surface at the given point.

virtual SPAunit_vector point_normal (const SPAposition &pos, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF) const =0

Finds the normal to this surface at a point on the surface nearest to the given position.

virtual SPAunit_vector point_outdir (const SPAposition &pos, const SPApar_pos &guess=*(SPApar_pos *) NULL_REF) const

Finds the outward direction from this surface at a point nearest the given position.

void point_perp (const SPAposition &pos, SPAposition &foot, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF, SPApar_pos &param_actual=*(SPApar_pos *) NULL_REF, logical f_weak=FALSE) const

Finds the point on this surface nearest to the given point.

void point_perp (const SPAposition &pos, SPAposition &foot, SPAunit_vector &normal, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF, SPApar_pos &param_actual=*(SPApar_pos *) NULL_REF, logical f_weak=FALSE) const

Finds the point on this surface nearest to the given point and, optionally, the normal to the surface at that point.

virtual void point_perp (const SPAposition &pos, SPAposition &foot, SPAunit_vector &normal, surf_princurv &cur, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF, SPApar_pos &param_actual=*(SPApar_pos *) NULL_REF, logical f_weak=FALSE) const =0

Finds the point on this surface nearest to the given point and, optionally, the normal to and the principal curvatures of the surface at that point.

surf_princurv point_prin_curv (const SPAposition &pos, const SPApar_pos &guess=*(SPApar_pos *) NULL_REF) const

Finds the principal axes of curvature of this surface at a given point and the curvatures in those directions, in a structure defined for the purpose.

virtual void point_prin_curv (const SPAposition &pos, SPAunit_vector &axis1, double &cur1, SPAunit_vector &axis2, double &cur2, const SPApar_pos &param_guess=*(SPApar_pos *) NULL_REF) const =0

Finds the principal axes of curvature of this surface at a given point, and the curvatures along these axes.

void restore_data ()

Restores the data for this surface from a save file.

virtual void save () const =0

Calls the virtual save method for the particular type of this surface.

void save_data () const

Saves the information for this surface to a save file.

void save_surface () const

Saves this surface if the surface is of an unknown type or NULL.

virtual logical singular_u (double uparam) const

Determines whether the parameterization of this surface is singular at the specified u-parameter value.

virtual logical singular_v (double vparam) const

Determines whether the parameterization of this surface is singular at the specified v-parameter value.

virtual int split_at_kinks_u (spline **&pieces, double curvature=0.0) const

Divides this surface along u into separate pieces that are smooth (and therefore suitable for offsetting or blending).

virtual int split_at_kinks_v (spline **&pieces, double curvature=0.0) const

Divides this surface along v into separate pieces that are smooth (and therefore suitable for offsetting or blending).

surface * subset (const SPApar_box &box) const

Constructs a subset copy, within the given parameter box, of this surface.

SPApar_box subset_box () const

Returns the subset box of this surface.

surface * subset_u (const SPAinterval &range) const

Constructs a subset copy, within the given u interval, of this surface.

SPAinterval subset_u_interval () const

Returns a subset interval of this surface, in u.

surface * subset_v (const SPAinterval &range) const

Constructs a subset copy within the given v interval.

SPAinterval subset_v_interval () const

Returns a subset interval of this surface, in v.

logical subsetted () const

Determines whether this surface has a significant subset range.

logical subsetted_u () const

Determines whether this surface has a significant subset range in the u direction.

logical subsetted_v () const

Determines whether this surface has a significant subset range in the v direction.

surface ()

Constructs a surface (default constructor).

logical test_point (const SPAposition &pos, const SPApar_pos &uv_guess=*(SPApar_pos *) NULL_REF, SPApar_pos &uv_actual=*(SPApar_pos *) NULL_REF) const

Determines whether a point lies on this surface to the system precision.

virtual logical test_point_tol (const SPAposition &pos, double tol=0, const SPApar_pos &uv_guess=*(SPApar_pos *) NULL_REF, SPApar_pos &uv_actual=*(SPApar_pos *) NULL_REF) const =0

Determines whether a point lies on this surface to the given tolerance.

virtual int type () const =0

Returns the type of this surface.

virtual const char * type_name () const =0

Returns the string "surface".

virtual curve * u_param_line (double vparam) const

Constructs a parameter line on this surface.

virtual logical undef () const

Determines whether this surface is defined or undefined.

logical undefined () const

Determines whether this surface is defined or undefined.

void unlimit ()

Removes the subsetting from this surface.

void unlimit_u ()

Removes the subsetting from this surface, in the u direction.

void unlimit_v ()

Removes the subsetting from this surface, in the v direction.

surface * unsubset () const

Constructs a copy of the unbounded surface underlying this one.

surface * unsubset_u () const

Constructs a copy of the unbounded (in u) surface underlying this one.

surface * unsubset_v () const

Constructs a copy of the unbounded (in v) surface underlying this one.

virtual curve * v_param_line (double uparam) const

Constructs a parameter line on the surface.

virtual ~surface ()

C++ destructor, deleting a surface.

Protected Member Functions

int finite_difference_derivatives (const SPApar_pos &param, SPAposition &pos, SPAvector **derivs, int nd, int nfound, double du, double dv, evaluate_surface_quadrant quad) const

Evaluate higher derivatives than are available accurately in evaluate by finite differencing.

Protected Attributes

SPApar_box subset_range

Range to which this surface is subsetted.

Detailed Description

Base class for all ACIS surface types, which defines the basic virtual functions that are supplied for all specific surface classes.

Role: The surface class is the base class that all ACIS surface types (plane, cone, sphere, torus, and spline) are derived. The surface class defines the basic virtual functions that are supplied for all specific surface classes. Some of these functions are pure; i.e., the derived classes must define their own version; others have default definitions that can be used by the derived classes.

All ACIS surfaces have a parameterization scheme defined for them; however, the analytic surfaces (plane, cone, sphere, and torus) are not considered parametric surfaces. The only true parametric surface is the spline surface.

The parameterization of any ACIS surface maps a rectangle within a 2D vector space (u,v-parameter space) into a 3D real vector space (xyz object space). A surface is closed in u (or v) if the opposite sides of the rectangle map into identical curves in object space. If the derivatives also match at these boundaries, the surface is periodic in that parameter. If one side of this rectangle maps into a single point in object space, this point is a parametric singularity. If the surface normal is not continuous at this point, the point is a surface singularity.

The parameterization can be either right-handed (i.e., the surface normal is the cross product of u and v) or left-handed (i.e., the normal is the cross product of v and u).

See also:: blend_support, int_cur, off_spl_sur, skin_spl_sur, surf_surf_int, surface_law_data, SPApar_box

Constructor & Destructor Documentation

surface::surface ( )

Constructs a surface (default constructor).

Role: Requests memory for this object but does not populate it.

virtual surface::~surface ( ) [virtual]

C++ destructor, deleting a surface.

Member Function Documentation

virtual int surface::accurate_derivs ( const SPApar_box & box = *(SPApar_box *) NULL_REF ) const [virtual]

Returns the number of derivatives of this surface that can be found accurately and relatively directly.

Role: Returns the number of derivatives that can be found by evaluate accurately and relatively directly, rather than by finite differencing over the given portion of the surface. If there is no limit to the number of accurate derivatives, returns the value ALL_SURFACE_DERIVATIVES.

Parameters:

box

portion of the surface to be considered (optional).

Reimplemented in cone, plane, sphere, spline, and torus.

virtual const double* surface::all_discontinuities_u	(	int &	n_discont,
		int	order
	)			`[virtual]`

Returns the number and parameter values of all discontinuities in u of this surface, up to the given order (maximum three).

Role: The returned array is read-only.

Parameters:

	n_discont	number of discontinuities found.
	order	maximum order of the discontinuities.

Reimplemented in spline.

virtual const double* surface::all_discontinuities_v	(	int &	n_discont,
		int	order
	)			`[virtual]`

Returns the number and parameter values of all discontinuities in v of this surface, up to the given order (maximum three).

Role: The returned array is read-only.

Parameters:

	n_discont	number of discontinuities found.
	order	maximum order of the discontinuities.

Reimplemented in spline.

virtual SPAbox surface::bound	(	const SPAbox &	box,
		const SPAtransf &	transf = `(SPAtransf ) NULL_REF`
	)			const `[virtual]`

Returns an object-space box bounding this surface.

Role: This box need not be the smallest box that contains the specified portion of the surface, but it must balance the tightness of the bound against the cost of the evaluation.

Parameters:

	box	the region of interest.
	transf	optional transformation.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPAbox surface::bound	(	const SPApar_box &	parbox = `(SPApar_box ) NULL_REF`,
		const SPAtransf &	transf = `(SPAtransf ) NULL_REF`
	)			const `[virtual]`

Returns an object-space box bounding this surface.

Role: This box need not be the smallest box that contains the specified portion of the surface, but it must balance the tightness of the bound against the cost of the evaluation.

Parameters:

	parbox	the region of interest.
	transf	optional transformation.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual void surface::change_event ( ) [virtual]

Notifies the derived type that this surface has been changed.

Role: Used when the subset_range has changed, so that the surface can update itself. The default version of this method does nothing.

Reimplemented in spline.

virtual check_status_list* surface::check	(	const check_fix &	input = `(const check_fix ) NULL_REF`,
		check_fix &	result = `(check_fix ) NULL_REF`,
		const check_status_list *	chks = `(const check_status_list *) NULL_REF`
	)			`[virtual]`

Checks for any data errors in this surface, and corrects the errors if possible.

Role: The various arguments provide control over which checks are made, which fixes can be applied and which fixes were actually applied. The function returns a list of errors that remain in the surface on exit.

The default for the set of flags which say which fixes are allowable is none (nothing is fixed). If the list of checks to be made is NULL, then every possible check will be made. Otherwise, the function will only check for things in the list. Note that it is possible for errors not in the input list to be returned, as certain problems preclude other checks being performed. In such situations, the return list will contain errors which were not requested, but which have prevented requested checks from being made.

Parameters:

	input	set of flags for fixes allowed.
	result	fixes applied.
	chks	checks to be made (default is none).

Reimplemented in spline.

virtual logical surface::closed_u ( ) const [virtual]

Determines whether this surface is closed, smoothly or not, in the u-parameter direction.

Role: Always returns TRUE if the corresponding periodic method returns TRUE.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::closed_v ( ) const [virtual]

Determines whether this surface is closed, smoothly or not, in the v-parameter direction.

Role: Always returns TRUE if the corresponding periodic method returns TRUE.

Reimplemented in cone, plane, sphere, spline, and torus.

surface* surface::copy_surf ( ) const

Makes a copy of this surface.

Role: This method calls make_copy.

virtual void surface::debug	(	const char *	title,
		FILE *	fp = `debug_file_ptr`
	)			const `[pure virtual]`

Prints out a title line and details about this surface to the debug file or any other specified file.

Parameters:

	title	title string.
	fp	FILE pointer.

Implemented in cone, plane, sphere, spline, and torus.

virtual surface* surface::deep_copy ( pointer_map * pm = NULL ) const [pure virtual]

Creates a copy of this object that does not share any data with the original.

Role: Allocates new storage for all member data and any pointers. Returns a pointer to the copied item.

In a deep copy, all the information about the copied item is self-contained in a new memory block. By comparison, a shallow copy stores only the first instance of the item in memory, and increments the reference count for each copy.

The pointer_map keeps a list of all pointers in the original object that have already been deep copied. For example, a deep copy of a complex model results in self contained data, but identical sub-parts within the model are allowed to share a single set of data.

Parameters:

pm

list of items within the object that are already deep copied.

Implemented in cone, plane, sphere, spline, and torus.

virtual const double* surface::discontinuities_u	(	int &	n_discont,
		int	order
	)			const `[virtual]`

Returns the number and parameter values of discontinuities in u of this surface, of the given order (maximum three), in a read-only array.

Parameters:

	n_discont	number of discontinuities found.
	order	order of the discontinuities.

Reimplemented in spline.

virtual const double* surface::discontinuities_v	(	int &	n_discont,
		int	order
	)			const `[virtual]`

Returns the number and parameter values of discontinuities in v of this surface, of the given order (maximum three), in a read-only array.

Parameters:

	n_discont	number of discontinuities found.
	order	order of the discontinuities.

Reimplemented in spline.

virtual int surface::discontinuous_at_u ( double u ) const [virtual]

Determines whether a particular value of u represents a discontinuity of this surface.

Parameters:

u

parameter value to test.

Reimplemented in spline.

virtual int surface::discontinuous_at_v ( double v ) const [virtual]

Determines whether a particular value of v represents a discontinuity of this surface.

Parameters:

v

parameter value to test.

Reimplemented in spline.

virtual void surface::eval	(	const SPApar_pos &	param,
		SPAposition &	pos,
		SPAvector *	first_derivs = `NULL`,
		SPAvector *	second_derivs = `NULL`
	)			const `[virtual]`

Finds the position on a parametric surface corresponding to the given parameter values, and optionally the first and second derivatives as well.

Parameters:

	param	parameter position at which to perform the evaluation.
	pos	position on surface at the specified parameter position.
	first_derivs	first derivatives (array of length 2 in the order Xu, Xv).
	second_derivs	second derivatives (array of length 3 in the order Xuu, Xuv, Xvv).

Reimplemented in cone, plane, sphere, spline, and torus.

virtual double surface::eval_cross	(	const SPApar_pos &	pos,
		const SPAunit_vector &	normal
	)			const `[virtual]`

Finds the curvature of a cross-sectional curve of the parametric surface at the point with the given parameter position.

Role: The cross-sectional curve is given by the intersection of the surface with a plane passing through the given point and with the given normal.

Parameters:

	pos	position on the interecting plane.
	normal	normal to the interecting plane.

Reimplemented in plane, sphere, and spline.

virtual SPAunit_vector surface::eval_normal ( const SPApar_pos & pos ) const [virtual]

Finds the normal to a parametric surface at the point with the given parameter position.

Parameters:

pos

parameter position at which to evaluate the surface normal.

Reimplemented in plane, sphere, spline, and torus.

virtual SPAunit_vector surface::eval_outdir ( const SPApar_pos & pos ) const [virtual]

Finds the outward direction from this surface at the point with the given parameter position.

Role: This method usually returns the normal, but if the nearest point is a singularity (like the apex of a cone), it still returns an outward direction.

Parameters:

pos

parameter position at which to evaluate the outward direction.

Reimplemented in cone, and spline.

virtual SPAposition surface::eval_position ( const SPApar_pos & pos ) const [virtual]

Finds the point on a parametric surface with the given parameter position.

Parameters:

pos

parameter position at which to evaluate the surface position.

Reimplemented in spline.

surf_princurv surface::eval_prin_curv ( const SPApar_pos & pos ) const

Finds the principal axes of curvature of this surface at the point with the given parameter position and the curvatures in those directions, in a structure defined for the purpose.

Parameters:

pos

parameter position at which to evaluate the curvature.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual void surface::eval_prin_curv	(	const SPApar_pos &	pos,
		SPAunit_vector &	axis1,
		double &	cur1,
		SPAunit_vector &	axis2,
		double &	cur2
	)			const `[virtual]`

Finds the principal axes of curvature of this surface at the point with the given parameter position, and the curvatures in those directions.

Parameters:

	pos	parameter position at which to evaluate the curvatures and curvature axes.
	axis1	first axis of curvature.
	cur1	curvature along the first axis.
	axis2	second axis of curvature.
	cur2	curvature along the second axis.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual int surface::evaluate	(	const SPApar_pos &	param,
		SPAposition &	pos,
		SPAvector **	derivs = `NULL`,
		int	nd = `0`,
		evaluate_surface_quadrant	quad = `evaluate_surface_unknown`
	)			const `[virtual]`

Calculates derivatives, of any order up to the number requested, and stores them in vectors provided by the user.

Role: This method returns the number of derivatives it was able to calculate; usually, this equals the requested number. A certain number are evaluated directly and accurately; higher derivatives are automatically calculated by finite differencing. The accuracy of these decreases with the order of the derivative, as the cost increases. Any of the pointers may be NULL, in which case the corresponding derivatives will not be returned. Otherwise they must point to arrays long enough for all the derivatives of that order.

Parameters:

	param	the parameter position at which the surface is to be evaluated.
	pos	point on the surface at the given parameter position.
	derivs	pointer arrays of derivatives.
	nd	the number of derivatives required.
	quad	the evaluation location - above, below, or "don't care" (for each parameter direction).

Reimplemented in cone, plane, sphere, spline, and torus.

virtual int surface::evaluate_iter	(	const SPApar_pos &	param,
		surface_evaldata *	data,
		SPAposition &	pos,
		SPAvector **	derivs = `NULL`,
		int	nd = `0`,
		evaluate_surface_quadrant	quad = `evaluate_surface_unknown`
	)			const `[virtual]`

Calculates derivatives, of any order up to the number requested, in an iterative fashion.

Role: The purpose of this method is the same as that of evaluate, but evaluate_iter is additionally supplied with a data object which contains results from a previous close evaluation, for use as initial values for any iteration involved. This object may furthermore be updated to reflect the results of this evaluation.

Parameters:

	param	the parameter position at which the surface is to be evaluated.
	data	data supplying initial values, and set to reflect the results of this evaluation.
	pos	point on the curve at the given parameter.
	derivs	pointer arrays of derivatives.
	nd	the number of derivatives required.
	quad	the evaluation location - above, below, or "don't care" (for each parameter direction).

Reimplemented in spline.

int surface::finite_difference_derivatives	(	const SPApar_pos &	param,
		SPAposition &	pos,
		SPAvector **	derivs,
		int	nd,
		int	nfound,
		double	du,
		double	dv,
		evaluate_surface_quadrant	quad
	)			const `[protected]`

Evaluate higher derivatives than are available accurately in evaluate by finite differencing.

Role: This method is available to any derived class for use in its own evaluate method. It calls back the evaluate function for adjacent points to evaluate a number of derivatives, so evaluate must ensure that this does not cause a further call to this method. See evaluate for details regarding the parameters.

Parameters:

	param	the parameter position at which the surface is to be evaluated.
	pos	point on the surface at the given parameter.
	derivs	pointer arrays of derivatives.
	nd	the number of derivatives required.
	nfound	the number of derivatives already evaluated, and directly evaluable in the neighborhood of the param.
	du	the finite differencing step to use in the u-direction.
	dv	the finite differencing step to use in the v-direction.
	quad	the evaluation location - above, below, or "don't care" (for each parameter direction).

virtual const discontinuity_info& surface::get_disc_info_u ( ) const [virtual]

Returns read-only access to a discontinuity_info object, if there is one, detailing discontinuities in u.

Role: The default version of this method returns NULL.

Reimplemented in spline.

virtual const discontinuity_info& surface::get_disc_info_v ( ) const [virtual]

Returns read-only access to a discontinuity_info object, if there is one, detailing discontinuities in v.

Role: The default version of this method returns NULL.

Reimplemented in spline.

virtual curve* surface::get_path ( ) const [inline, virtual]

Returns the sweep path curve for this surface.

Reimplemented in cone, plane, spline, and torus.

virtual sweep_path_type surface::get_path_type ( ) const [inline, virtual]

Returns the sweep path type for this surface.

Reimplemented in cone, plane, spline, and torus.

virtual curve* surface::get_profile ( double param ) const [inline, virtual]

Returns the sweep profile on this surface.

Parameters:

param

parameter at which to get the profile.

Reimplemented in cone, spline, and torus.

virtual law* surface::get_rail ( ) const [inline, virtual]

Returns the rail law for this swept surface.

Reimplemented in cone, plane, spline, and torus.

virtual logical surface::left_handed_uv ( ) const [virtual]

Indicates whether the parameter coordinate system of this surface is right-handed or left-handed.

Role: With a right-handed system, the outward normal at any point is given by the cross product of the increasing u-direction with the increasing v-direction, in that order. With a left-handed system, the outward normal is in the opposite direction from this cross product.

Reimplemented in cone, plane, sphere, spline, and torus.

void surface::limit ( const SPApar_box & box )

Subsets this surface in place, according to the given parameter box.

Parameters:

box

parameter box defining the subset.

void surface::limit_u ( const SPAinterval & range )

Subsets this surface in place, according to the given interval in u.

Parameters:

range

interval defining the subset.

void surface::limit_v ( const SPAinterval & range )

Subsets this surface in place, according to the given interval in v.

Parameters:

range

interval defining the subset.

virtual surface* surface::make_copy ( ) const [pure virtual]

Makes a copy of this surface on the heap, and returns a pointer to it.

Implemented in cone, plane, sphere, spline, and torus.

virtual surface_evaldata* surface::make_evaldata ( ) const [virtual]

Constructs a data object to retain evaluation information across calls to evaluate_iter.

Role: This is to allow subsidiary calls within an iterative evaluator to start iteration much closer to the required result than is possible just using the curve information itself.

Reimplemented in spline.

virtual logical surface::need_save_as_approx	(	int	save_to_version,
		logical	check_progenitors
	)			const `[virtual]`

Queries whether the object needs to be saved to an old version as an approximation.

Role: Called by SAT save APIs with check_progenitors==TRUE to determine if an object needs to be tolerantly simplified before being saved to an old version. The check_progenitors flag indicates that the object should call need_save_as_approx() on any curve or surface construction geometry upon which it depends, and return TRUE if any of the progenitors do. Customers with their own derived curve or surface types should override this routine to return true whenever they want their geometry to be imported (as a B-spline approximation) into other applications or when saving to a version of their application before the derived geometry type in question existed.

Parameters:

	save_to_version	version to which the object will be saved
	check_progenitors	if TRUE, query construction geometry and base class as well

Reimplemented in spline.

virtual surface& surface::negate ( ) [pure virtual]

Reverses the sense of this surface.

Implemented in cone, plane, sphere, spline, and torus.

virtual surf_normcone surface::normal_cone	(	const SPApar_box &	parbox,
		logical	approx_OK = `FALSE`,
		const SPAtransf &	transf = `(SPAtransf ) NULL_REF`
	)			const `[virtual]`

Returns a cone bounding the normal direction of this surface.

Role: The cone is deemed to have its apex at the origin and have a given axis direction and (positive) half-angle. If the logical argument is TRUE, then this method finds a quick approximation. The approximate result may lie wholly within or wholly outside the guaranteed bound (obtained with a FALSE argument), but may not cross from inside to outside. Flags in the turned object indicate whether the cone is the best available and, if not, whether this result is inside or outside the best cone.

Parameters:

	parbox	the given region.
	approx_OK	approximate result is ok.
	transf	transformation to apply.

Reimplemented in cone, plane, sphere, spline, and torus.

logical surface::operator!= ( const surface & surf ) const [inline]

Tests this surface for inequality to another surface.

Role: This method does not guarantee equality for effectively-equal surfaces, but it is guaranteed to determine inequality if the two surfaces are not equal. Use this result for optimization.

Parameters:

surf

surface to compare for inequality.

virtual surface& surface::operator*= ( const SPAtransf & transf ) [pure virtual]

Transforms this surface by the given transformation.

Parameters:

transf

transformation to apply.

Implemented in cone, plane, sphere, spline, and torus.

virtual logical surface::operator== ( const surface & surf ) const [virtual]

Tests this surface for equality to another surface.

Role: This method does not guarantee equality for effectively-equal surfaces, but it is guaranteed to determine inequality if the two surfaces are not equal. Use this result for optimization.

Parameters:

surf

surface to compare for equality.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPApar_pos surface::param	(	const SPAposition &	pos,
		const SPApar_pos &	guess = `(SPApar_pos ) NULL_REF`
	)			const `[virtual]`

Finds the parameter position of a given point on this surface, given an optional first guess.

Parameters:

	pos	the position for which the parameter position is to be found.
	param_guess	parameter guess.

Reimplemented in cone, plane, sphere, spline, and torus.

SPApar_dir surface::param_dir	(	const SPAunit_vector &	dir,
		const SPApar_pos &	pos
	)			const

Finds the direction in parameter space of a given object-space direction on this surface, at a given parameter position.

Parameters:

	dir	object-space direction for which the parameter-space direction is to be determined.
	pos	parameter position at which the direction is to be determined.

virtual double surface::param_period_u ( ) const [virtual]

Returns the period, in u, of a periodic parametric surface.

Role: If the surface is not parametric, or is not periodic in the u-direction, this method returns 0.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual double surface::param_period_v ( ) const [virtual]

Returns the period, in v, of a periodic parametric surface.

Role: If the surface is not parametric or is not periodic in the v-direction, this method returns 0.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPApar_box surface::param_range ( const SPAbox & box = *(SPAbox *) NULL_REF ) const [virtual]

Returns the principal parameter range of this surface.

Role: A periodic surface is defined for all parameter values in the periodic direction by reducing the given parameter modulo the period into this principal range. For a surface that is open or nonperiodic in the chosen direction, the surface evaluation functions are defined only for the parameter values in the returned range.

If a box is provided, the parameter range returned may be restricted to a portion of the surface that is guaranteed to contain all portions of the surface that lie within the region of interest. If none is provided and the parameter range in some direction is unbounded, then this method returns an empty interval.

Parameters:

box

box restricting the result.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPAinterval surface::param_range_u ( const SPAbox & box = *(SPAbox *) NULL_REF ) const [virtual]

Returns the principal parameter range of a surface in the u-parameter direction.

Role: A periodic surface is defined for all parameter values in the periodic direction by reducing the given parameter modulo the period into this principal range. For a surface that is open or nonperiodic in the chosen direction, the surface evaluation functions are defined only for the parameter values in the returned range.

If a box is provided, the parameter range returned may be restricted to a portion of the surface that is guaranteed to contain all portions of the surface that lie within the region of interest. If none is provided and the parameter range in some direction is unbounded, then this method returns an empty interval.

Parameters:

box

box restricting the result.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPAinterval surface::param_range_v ( const SPAbox & box = *(SPAbox *) NULL_REF ) const [virtual]

Returns the principal parameter range of a surface in the v-parameter direction.

Role: A periodic surface is defined for all parameter values in the periodic direction by reducing the given parameter modulo the period into this principal range. For a surface that is open or nonperiodic in the chosen direction, the surface evaluation functions are defined only for the parameter values in the returned range.

If a box is provided, the parameter range returned may be restricted to a portion of the surface that is guaranteed to contain all portions of the surface that lie within the region of interest. If none is provided and the parameter range in some direction is unbounded, then this method returns an empty interval.

Parameters:

box

box restricting the result.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual SPApar_vec surface::param_unitvec	(	const SPAunit_vector &	dir,
		const SPApar_pos &	pos
	)			const `[virtual]`

Finds the rate of change in the surface parameter corresponding to a unit velocity in a given object-space direction, at a given position in parameter space.

Parameters:

	dir	object-space direction for which the result is determined.
	pos	parameter position at which the result is determined.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::parametric ( ) const [virtual]

Returns TRUE if this surface is a parametric surface - otherwise returns FALSE.

Role: This result reflects the fundamental nature of the surface and is used by the ACIS kernel to avoid using parameters when they are not necessary. For a surface, the ACIS kernel does not use any of the parameter-based functions, though they are implemented for the sake of those components and applications that prefer parameter-based representations of every surface.

Whether to declare a surface parametric or not depends on the implementation of the point-based evaluations. If the availability of a good approximation to the point's parameter values makes no significant improvement to the speed of these functions, then the surface is nonparametric; otherwise, it is parametric. A plane is an obvious nonparametric surface; a B-spline is a parametric surface.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::periodic_u ( ) const [virtual]

Determines if this surface is periodic in the u-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::periodic_v ( ) const [virtual]

Determines if this surface is periodic in the v-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::planar	(	SPAposition &	pos,
		SPAunit_vector &	normal
	)			const `[virtual]`

Reports whether this surface is planar.

Parameters:

	pos	point on the surface.
	normal	the planar normal.

Reimplemented in plane, and spline.

virtual double surface::point_cross	(	const SPAposition &	pos,
		const SPAunit_vector &	normal,
		const SPApar_pos &	param_guess = `(SPApar_pos ) NULL_REF`
	)			const `[virtual]`

Finds the curvature of a cross-sectional curve of this surface at the given point.

Role: The cross-sectional curve is given by the intersection of the surface with a plane passing through the given point and with the given normal.

Parameters:

	pos	position on the plane.
	normal	normal to the plane.
	param_guess	parameter guess.

Reimplemented in plane, sphere, and spline.

virtual SPAunit_vector surface::point_normal	(	const SPAposition &	pos,
		const SPApar_pos &	param_guess = `(SPApar_pos ) NULL_REF`
	)			const `[pure virtual]`

Finds the normal to this surface at a point on the surface nearest to the given position.

Parameters:

	pos	the given position.
	param_guess	parameter guess.

Implemented in cone, plane, sphere, spline, and torus.

virtual SPAunit_vector surface::point_outdir	(	const SPAposition &	pos,
		const SPApar_pos &	guess = `(SPApar_pos ) NULL_REF`
	)			const `[virtual]`

Finds the outward direction from this surface at a point nearest the given position.

Role: This method usually returns the normal, but if the nearest point is a singularity (like the apex of a cone), this method still returns an outward direction. The base class definition returns point_normal, which is used by default on simple surfaces.

Parameters:

	pos	given position.
	guess	parameter guess.

Reimplemented in cone, spline, and torus.

void surface::point_perp	(	const SPAposition &	pos,
		SPAposition &	foot,
		const SPApar_pos &	param_guess = `(SPApar_pos)NULL_REF`,
		SPApar_pos &	param_actual = `(SPApar_pos)NULL_REF`,
		logical	f_weak = `FALSE`
	)			const `[inline]`

Finds the point on this surface nearest to the given point.

Role: If the surface is parametric, this method also returns the parameter values at the found point.

Parameters:

	pos	the input position.
	foot	the position on the surface.
	param_guess	parameter guess.
	param_actual	actual parameter position.
	f_weak	weak flag - for internal use.

Reimplemented in cone, plane, sphere, spline, and torus.

void surface::point_perp	(	const SPAposition &	pos,
		SPAposition &	foot,
		SPAunit_vector &	normal,
		const SPApar_pos &	param_guess = `(SPApar_pos)NULL_REF`,
		SPApar_pos &	param_actual = `(SPApar_pos)NULL_REF`,
		logical	f_weak = `FALSE`
	)			const `[inline]`

Finds the point on this surface nearest to the given point and, optionally, the normal to the surface at that point.

Role: If the surface is parametric, this method also returns the parameter values at the found point.

Parameters:

	pos	the input position.
	foot	the position on the surface.
	normal	the returned normal.
	param_guess	parameter guess.
	param_actual	actual parameter position.
	f_weak	weak flag - for internal use.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual void surface::point_perp	(	const SPAposition &	pos,
		SPAposition &	foot,
		SPAunit_vector &	normal,
		surf_princurv &	cur,
		const SPApar_pos &	param_guess = `(SPApar_pos ) NULL_REF`,
		SPApar_pos &	param_actual = `(SPApar_pos ) NULL_REF`,
		logical	f_weak = `FALSE`
	)			const `[pure virtual]`

Finds the point on this surface nearest to the given point and, optionally, the normal to and the principal curvatures of the surface at that point.

Role: If the surface is parametric, this method also returns the parameter values at the found point.

Parameters:

	pos	the input position.
	foot	the position on the surface.
	normal	the returned normal.
	cur	the principal curvature.
	param_guess	parameter guess.
	param_actual	actual parameter position.
	f_weak	weak flag - for internal use.

Implemented in cone, plane, sphere, spline, and torus.

surf_princurv surface::point_prin_curv	(	const SPAposition &	pos,
		const SPApar_pos &	guess = `(SPApar_pos ) NULL_REF`
	)			const

Finds the principal axes of curvature of this surface at a given point and the curvatures in those directions, in a structure defined for the purpose.

Parameters:

	pos	position at which to evaluate the curvature.
	guess	parameter guess

Reimplemented in cone, plane, sphere, spline, and torus.

virtual void surface::point_prin_curv	(	const SPAposition &	pos,
		SPAunit_vector &	axis1,
		double &	cur1,
		SPAunit_vector &	axis2,
		double &	cur2,
		const SPApar_pos &	param_guess = `(SPApar_pos ) NULL_REF`
	)			const `[pure virtual]`

Finds the principal axes of curvature of this surface at a given point, and the curvatures along these axes.

Parameters:

	pos	position at which to evaluate the curvatures and curvature axes.
	axis1	first axis of curvature.
	cur1	curvature along the first axis.
	axis2	second axis of curvature.
	cur2	curvature along the second axis.
	param_guess	parameter guess.

Implemented in cone, plane, sphere, spline, and torus.

void surface::restore_data ( )

Restores the data for this surface from a save file.

Role:

    if (restore_version_number >= BNDSUR_VERSION)
 	     read_interval		subset u interval
 	     read_interval		subset v interval

Reimplemented in cone, plane, sphere, spline, and torus.

virtual void surface::save ( ) const [pure virtual]

Calls the virtual save method for the particular type of this surface.

Implemented in cone, plane, sphere, spline, and torus.

void surface::save_data ( ) const

Saves the information for this surface to a save file.

Reimplemented in cone, plane, sphere, spline, and torus.

void surface::save_surface ( ) const

Saves this surface if the surface is of an unknown type or NULL.

Role: Checks for NULL, then calls the save method.

virtual logical surface::singular_u ( double uparam ) const [virtual]

Determines whether the parameterization of this surface is singular at the specified u-parameter value.

Role: The only singularity recognized is where every value of the nonconstant parameter generates the same object-space point, and these can only occur at the ends of the parameter range.

Parameters:

uparam

u-parameter value to test.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::singular_v ( double vparam ) const [virtual]

Determines whether the parameterization of this surface is singular at the specified v-parameter value.

Role: The only singularity recognized is where every value of the nonconstant parameter generates the same object-space point, and these can only occur at the ends of the parameter range.

Parameters:

vparam

v-parameter value to test.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual int surface::split_at_kinks_u	(	spline **&	pieces,
		double	curvature = `0.0`
	)			const `[virtual]`

Divides this surface along u into separate pieces that are smooth (and therefore suitable for offsetting or blending).

Role: The surface is split if the curvature exceeds the minimum curvature argument. If it is closed after this, it is then split into two. The split pieces are stored in the pieces argument. The function returns the count of split pieces. Only implemented for splines and elliptical cones.

Parameters:

	pieces	the returned split pieces.
	curvature	the minimum curvature.

Reimplemented in spline.

virtual int surface::split_at_kinks_v	(	spline **&	pieces,
		double	curvature = `0.0`
	)			const `[virtual]`

Divides this surface along v into separate pieces that are smooth (and therefore suitable for offsetting or blending).

Role: The surface is split if the curvature exceeds the minimum curvature argument. If it is closed after this, it is then split into two. The split pieces are stored in the pieces argument. The function returns the count of split pieces. Only implemented for splines and elliptical cones.

Parameters:

	pieces	the returned split pieces.
	curvature	the minimum curvature.

Reimplemented in cone, and spline.

surface* surface::subset ( const SPApar_box & box ) const

Constructs a subset copy, within the given parameter box, of this surface.

Parameters:

box

parameter box.

Reimplemented in spline.

SPApar_box surface::subset_box ( ) const

Returns the subset box of this surface.

surface* surface::subset_u ( const SPAinterval & range ) const

Constructs a subset copy, within the given u interval, of this surface.

Parameters:

range

u interval.

SPAinterval surface::subset_u_interval ( ) const

Returns a subset interval of this surface, in u.

surface* surface::subset_v ( const SPAinterval & range ) const

Constructs a subset copy within the given v interval.

Parameters:

range

v interval

SPAinterval surface::subset_v_interval ( ) const

Returns a subset interval of this surface, in v.

logical surface::subsetted ( ) const

Determines whether this surface has a significant subset range.

logical surface::subsetted_u ( ) const

Determines whether this surface has a significant subset range in the u direction.

logical surface::subsetted_v ( ) const

Determines whether this surface has a significant subset range in the v direction.

logical surface::test_point	(	const SPAposition &	pos,
		const SPApar_pos &	uv_guess = `(SPApar_pos)NULL_REF`,
		SPApar_pos &	uv_actual = `(SPApar_pos)NULL_REF`
	)			const `[inline]`

Determines whether a point lies on this surface to the system precision.

Parameters:

	pos	position to test.
	uv_guess	parameter guess.
	uv_actual	actual parameter.

virtual logical surface::test_point_tol	(	const SPAposition &	pos,
		double	tol = `0`,
		const SPApar_pos &	uv_guess = `(SPApar_pos ) NULL_REF`,
		SPApar_pos &	uv_actual = `(SPApar_pos ) NULL_REF`
	)			const `[pure virtual]`

Determines whether a point lies on this surface to the given tolerance.

Parameters:

	pos	position to test.
	tol	tolerance to use (defaults to SPAresabs).
	uv_guess	parameter guess.
	uv_actual	actual parameter.

Implemented in cone, plane, sphere, spline, and torus.

virtual int surface::type ( ) const [pure virtual]

Returns the type of this surface.

Implemented in cone, plane, sphere, spline, and torus.

virtual const char* surface::type_name ( ) const [pure virtual]

Returns the string "surface".

Implemented in cone, plane, sphere, spline, and torus.

virtual curve* surface::u_param_line ( double vparam ) const [virtual]

Constructs a parameter line on this surface.

Role: A u-parameter line runs in the direction of increasing u parameter, at constant v. The parameterization in the nonconstant direction matches that of the surface, and it has the range obtained by the use of param_range_u. If the supplied constant parameter value is outside the valid range for the surface, or if it is at a singularity, this method returns NULL.

The new curve is constructed in free storage, so it is the responsibility of the caller to ensure that it is correctly deleted.

Parameters:

vparam

v parameter defining the parameter line.

Reimplemented in cone, plane, sphere, spline, and torus.

virtual logical surface::undef ( ) const [virtual]

Determines whether this surface is defined or undefined.

Role: A NULL or generic surface is always undefined; for other surfaces, it depend on their contents.

Reimplemented in cone, plane, sphere, spline, and torus.

logical surface::undefined ( ) const [inline]

Determines whether this surface is defined or undefined.

Role: A NULL or generic surface is always undefined; for other surfaces, it depends on their contents.

void surface::unlimit ( )

Removes the subsetting from this surface.

void surface::unlimit_u ( )

Removes the subsetting from this surface, in the u direction.

void surface::unlimit_v ( )

Removes the subsetting from this surface, in the v direction.

surface* surface::unsubset ( ) const

Constructs a copy of the unbounded surface underlying this one.

surface* surface::unsubset_u ( ) const

Constructs a copy of the unbounded (in u) surface underlying this one.

surface* surface::unsubset_v ( ) const

Constructs a copy of the unbounded (in v) surface underlying this one.

virtual curve* surface::v_param_line ( double uparam ) const [virtual]

Constructs a parameter line on the surface.

Role: A v-parameter line runs in the direction of increasing v parameter, at constant u. The parameterization int he nonconstant direction matches that of the surface, and it has the range obtained by the use of param_range_v. If the supplied constant parameter value is outside the valid range for the surface, or if it is at a singularity, this method returns NULL.

The new curve is constructed in free storage, so it is the responsibility of the caller to ensure that it is correctly deleted.

Parameters:

uparam

u parameter defining the parameter line.

Reimplemented in cone, plane, sphere, spline, and torus.

Member Data Documentation

SPApar_box surface::subset_range [protected]

Range to which this surface is subsetted.


Public Member Functions
virtual int	accurate_derivs (const SPApar_box &box=(SPApar_box ) NULL_REF) const
	Returns the number of derivatives of this `surface` that can be found accurately and relatively directly.
virtual const double *	all_discontinuities_u (int &n_discont, int order)
	Returns the number and parameter values of all discontinuities in u of this `surface`, up to the given order (maximum three).
virtual const double *	all_discontinuities_v (int &n_discont, int order)
	Returns the number and parameter values of all discontinuities in v of this `surface`, up to the given order (maximum three).
virtual SPAbox	bound (const SPAbox &box, const SPAtransf &transf=(SPAtransf ) NULL_REF) const
	Returns an object-space box bounding this `surface`.
virtual SPAbox	bound (const SPApar_box &parbox=(SPApar_box ) NULL_REF, const SPAtransf &transf=(SPAtransf ) NULL_REF) const
	Returns an object-space box bounding this `surface`.
virtual void	change_event ()
	Notifies the derived type that this `surface` has been changed.
virtual check_status_list *	check (const check_fix &input=(const check_fix ) NULL_REF, check_fix &result=(check_fix ) NULL_REF, const check_status_list chks=(const check_status_list ) NULL_REF)
	Checks for any data errors in this `surface`, and corrects the errors if possible.
virtual logical	closed_u () const
	Determines whether this `surface` is closed, smoothly or not, in the u-parameter direction.
virtual logical	closed_v () const
	Determines whether this `surface` is closed, smoothly or not, in the v-parameter direction.
surface *	copy_surf () const
	Makes a copy of this `surface`.
virtual void	debug (const char title, FILE fp=debug_file_ptr) const =0
	Prints out a title line and details about this `surface` to the debug file or any other specified file.
virtual surface *	deep_copy (pointer_map *pm=NULL) const =0
	Creates a copy of this object that does not share any data with the original.
virtual const double *	discontinuities_u (int &n_discont, int order) const
	Returns the number and parameter values of discontinuities in u of this `surface`, of the given order (maximum three), in a read-only array.
virtual const double *	discontinuities_v (int &n_discont, int order) const
	Returns the number and parameter values of discontinuities in v of this `surface`, of the given order (maximum three), in a read-only array.
virtual int	discontinuous_at_u (double u) const
	Determines whether a particular value of u represents a discontinuity of this `surface`.
virtual int	discontinuous_at_v (double v) const
	Determines whether a particular value of v represents a discontinuity of this `surface`.
virtual void	eval (const SPApar_pos &param, SPAposition &pos, SPAvector first_derivs=NULL, SPAvector second_derivs=NULL) const
	Finds the position on a parametric surface corresponding to the given parameter values, and optionally the first and second derivatives as well.
virtual double	eval_cross (const SPApar_pos &pos, const SPAunit_vector &normal) const
	Finds the curvature of a cross-sectional curve of the parametric surface at the point with the given parameter position.
virtual SPAunit_vector	eval_normal (const SPApar_pos &pos) const
	Finds the normal to a parametric surface at the point with the given parameter position.
virtual SPAunit_vector	eval_outdir (const SPApar_pos &pos) const
	Finds the outward direction from this `surface` at the point with the given parameter position.
virtual SPAposition	eval_position (const SPApar_pos &pos) const
	Finds the point on a parametric surface with the given parameter position.
surf_princurv	eval_prin_curv (const SPApar_pos &pos) const
	Finds the principal axes of curvature of this `surface` at the point with the given parameter position and the curvatures in those directions, in a structure defined for the purpose.
virtual void	eval_prin_curv (const SPApar_pos &pos, SPAunit_vector &axis1, double &cur1, SPAunit_vector &axis2, double &cur2) const
	Finds the principal axes of curvature of this `surface` at the point with the given parameter position, and the curvatures in those directions.
virtual int	evaluate (const SPApar_pos &param, SPAposition &pos, SPAvector **derivs=NULL, int nd=0, evaluate_surface_quadrant quad=evaluate_surface_unknown) const
	Calculates derivatives, of any order up to the number requested, and stores them in vectors provided by the user.
virtual int	evaluate_iter (const SPApar_pos &param, surface_evaldata data, SPAposition &pos, SPAvector *derivs=NULL, int nd=0, evaluate_surface_quadrant quad=evaluate_surface_unknown) const
	Calculates derivatives, of any order up to the number requested, in an iterative fashion.
virtual const discontinuity_info &	get_disc_info_u () const
	Returns read-only access to a `discontinuity_info` object, if there is one, detailing discontinuities in u.
virtual const discontinuity_info &	get_disc_info_v () const
	Returns read-only access to a `discontinuity_info` object, if there is one, detailing discontinuities in v.
virtual curve *	get_path () const
	Returns the sweep path curve for this `surface`.
virtual sweep_path_type	get_path_type () const
	Returns the sweep path type for this `surface`.
virtual curve *	get_profile (double param) const
	Returns the sweep profile on this `surface`.
virtual law *	get_rail () const
	Returns the rail law for this swept surface.
virtual logical	left_handed_uv () const
	Indicates whether the parameter coordinate system of this `surface` is right-handed or left-handed.
void	limit (const SPApar_box &box)
	Subsets this `surface` in place, according to the given parameter box.
void	limit_u (const SPAinterval &range)
	Subsets this `surface` in place, according to the given interval in u.
void	limit_v (const SPAinterval &range)
	Subsets this `surface` in place, according to the given interval in v.
virtual surface *	make_copy () const =0
	Makes a copy of this `surface` on the heap, and returns a pointer to it.
virtual surface_evaldata *	make_evaldata () const
	Constructs a data object to retain evaluation information across calls to `evaluate_iter`.
virtual logical	need_save_as_approx (int save_to_version, logical check_progenitors) const
	Queries whether the object needs to be saved to an old version as an approximation.
virtual surface &	negate ()=0
	Reverses the sense of this `surface`.
virtual surf_normcone	normal_cone (const SPApar_box &parbox, logical approx_OK=FALSE, const SPAtransf &transf=(SPAtransf ) NULL_REF) const
	Returns a cone bounding the normal direction of this `surface`.
logical	operator!= (const surface &surf) const
	Tests this `surface` for inequality to another surface.
virtual surface &	operator*= (const SPAtransf &transf)=0
	Transforms this `surface` by the given transformation.
virtual logical	operator== (const surface &surf) const
	Tests this `surface` for equality to another surface.
virtual SPApar_pos	param (const SPAposition &pos, const SPApar_pos &guess=(SPApar_pos ) NULL_REF) const
	Finds the parameter position of a given point on this `surface`, given an optional first guess.
SPApar_dir	param_dir (const SPAunit_vector &dir, const SPApar_pos &pos) const
	Finds the direction in parameter space of a given object-space direction on this `surface`, at a given parameter position.
virtual double	param_period_u () const
	Returns the period, in u, of a periodic parametric surface.
virtual double	param_period_v () const
	Returns the period, in v, of a periodic parametric surface.
virtual SPApar_box	param_range (const SPAbox &box=(SPAbox ) NULL_REF) const
	Returns the principal parameter range of this `surface`.
virtual SPAinterval	param_range_u (const SPAbox &box=(SPAbox ) NULL_REF) const
	Returns the principal parameter range of a surface in the u-parameter direction.
virtual SPAinterval	param_range_v (const SPAbox &box=(SPAbox ) NULL_REF) const
	Returns the principal parameter range of a surface in the v-parameter direction.
virtual SPApar_vec	param_unitvec (const SPAunit_vector &dir, const SPApar_pos &pos) const
	Finds the rate of change in the surface parameter corresponding to a unit velocity in a given object-space direction, at a given position in parameter space.
virtual logical	parametric () const
	Returns `TRUE` if this `surface` is a parametric surface - otherwise returns `FALSE`.
virtual logical	periodic_u () const
	Determines if this `surface` is periodic in the u-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).
virtual logical	periodic_v () const
	Determines if this `surface` is periodic in the v-parameter direction (i.e., if it is smoothly closed, so that faces can run over the seam).
virtual logical	planar (SPAposition &pos, SPAunit_vector &normal) const
	Reports whether this `surface` is planar.
virtual double	point_cross (const SPAposition &pos, const SPAunit_vector &normal, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF) const
	Finds the curvature of a cross-sectional curve of this `surface` at the given point.
virtual SPAunit_vector	point_normal (const SPAposition &pos, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF) const =0
	Finds the normal to this `surface` at a point on the surface nearest to the given position.
virtual SPAunit_vector	point_outdir (const SPAposition &pos, const SPApar_pos &guess=(SPApar_pos ) NULL_REF) const
	Finds the outward direction from this `surface` at a point nearest the given position.
void	point_perp (const SPAposition &pos, SPAposition &foot, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF, SPApar_pos &param_actual=(SPApar_pos ) NULL_REF, logical f_weak=FALSE) const
	Finds the point on this `surface` nearest to the given point.
void	point_perp (const SPAposition &pos, SPAposition &foot, SPAunit_vector &normal, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF, SPApar_pos &param_actual=(SPApar_pos ) NULL_REF, logical f_weak=FALSE) const
	Finds the point on this `surface` nearest to the given point and, optionally, the normal to the surface at that point.
virtual void	point_perp (const SPAposition &pos, SPAposition &foot, SPAunit_vector &normal, surf_princurv &cur, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF, SPApar_pos &param_actual=(SPApar_pos ) NULL_REF, logical f_weak=FALSE) const =0
	Finds the point on this `surface` nearest to the given point and, optionally, the normal to and the principal curvatures of the surface at that point.
surf_princurv	point_prin_curv (const SPAposition &pos, const SPApar_pos &guess=(SPApar_pos ) NULL_REF) const
	Finds the principal axes of curvature of this `surface` at a given point and the curvatures in those directions, in a structure defined for the purpose.
virtual void	point_prin_curv (const SPAposition &pos, SPAunit_vector &axis1, double &cur1, SPAunit_vector &axis2, double &cur2, const SPApar_pos &param_guess=(SPApar_pos ) NULL_REF) const =0
	Finds the principal axes of curvature of this `surface` at a given point, and the curvatures along these axes.
void	restore_data ()
	Restores the data for this `surface` from a save file.
virtual void	save () const =0
	Calls the virtual `save` method for the particular type of this `surface`.
void	save_data () const
	Saves the information for this `surface` to a save file.
void	save_surface () const
	Saves this `surface` if the surface is of an unknown type or `NULL`.
virtual logical	singular_u (double uparam) const
	Determines whether the parameterization of this `surface` is singular at the specified u-parameter value.
virtual logical	singular_v (double vparam) const
	Determines whether the parameterization of this `surface` is singular at the specified v-parameter value.
virtual int	split_at_kinks_u (spline **&pieces, double curvature=0.0) const
	Divides this `surface` along u into separate pieces that are smooth (and therefore suitable for offsetting or blending).
virtual int	split_at_kinks_v (spline **&pieces, double curvature=0.0) const
	Divides this `surface` along v into separate pieces that are smooth (and therefore suitable for offsetting or blending).
surface *	subset (const SPApar_box &box) const
	Constructs a subset copy, within the given parameter box, of this surface.
SPApar_box	subset_box () const
	Returns the subset box of this `surface`.
surface *	subset_u (const SPAinterval &range) const
	Constructs a subset copy, within the given u interval, of this surface.
SPAinterval	subset_u_interval () const
	Returns a subset interval of this `surface`, in u.
surface *	subset_v (const SPAinterval &range) const
	Constructs a subset copy within the given v interval.
SPAinterval	subset_v_interval () const
	Returns a subset interval of this `surface`, in v.
logical	subsetted () const
	Determines whether this `surface` has a significant subset range.
logical	subsetted_u () const
	Determines whether this `surface` has a significant subset range in the u direction.
logical	subsetted_v () const
	Determines whether this `surface` has a significant subset range in the v direction.
	surface ()
	Constructs a `surface` (default constructor).
logical	test_point (const SPAposition &pos, const SPApar_pos &uv_guess=(SPApar_pos ) NULL_REF, SPApar_pos &uv_actual=(SPApar_pos ) NULL_REF) const
	Determines whether a point lies on this `surface` to the system precision.
virtual logical	test_point_tol (const SPAposition &pos, double tol=0, const SPApar_pos &uv_guess=(SPApar_pos ) NULL_REF, SPApar_pos &uv_actual=(SPApar_pos ) NULL_REF) const =0
	Determines whether a point lies on this `surface` to the given tolerance.
virtual int	type () const =0
	Returns the type of this `surface`.
virtual const char *	type_name () const =0
	Returns the string `"surface"`.
virtual curve *	u_param_line (double vparam) const
	Constructs a parameter line on this `surface`.
virtual logical	undef () const
	Determines whether this `surface` is defined or undefined.
logical	undefined () const
	Determines whether this `surface` is defined or undefined.
void	unlimit ()
	Removes the subsetting from this `surface`.
void	unlimit_u ()
	Removes the subsetting from this `surface`, in the u direction.
void	unlimit_v ()
	Removes the subsetting from this `surface`, in the v direction.
surface *	unsubset () const
	Constructs a copy of the unbounded surface underlying this one.
surface *	unsubset_u () const
	Constructs a copy of the unbounded (in u) surface underlying this one.
surface *	unsubset_v () const
	Constructs a copy of the unbounded (in v) surface underlying this one.
virtual curve *	v_param_line (double uparam) const
	Constructs a parameter line on the surface.
virtual	~surface ()
	C++ destructor, deleting a `surface`.
Protected Member Functions
int	finite_difference_derivatives (const SPApar_pos &param, SPAposition &pos, SPAvector **derivs, int nd, int nfound, double du, double dv, evaluate_surface_quadrant quad) const
	Evaluate higher derivatives than are available accurately in `evaluate` by finite differencing.
Protected Attributes
SPApar_box	subset_range
	Range to which this `surface` is subsetted.

surface Class Reference [surfaces]

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

surface Class Reference
[surfaces]