This class is an abstraction for evaluating NURBS curves. More...

#include "nurbsCurveEvaluator.h"

Inheritance diagram for NurbsCurveEvaluator:

Public Types
typedef pvector< LPoint3 >	Vert3Array

typedef epvector< LVecBase4 >	Vert4Array

Public Member Functions
PN_stdfloat	get_extended_vertex (int i, int d) const
	Returns an n-dimensional vertex value. More...

PN_stdfloat	get_knot (int i) const

int	get_num_knots () const

int	get_num_segments () const
	Returns the number of piecewise continuous segments in the curve. More...

int	get_num_vertices () const

int	get_order () const
	Returns the order of the curve as set by a previous call to set_order(). More...

const LVecBase4 &	get_vertex (int i) const

LVecBase4	get_vertex (int i, const NodePath &rel_to) const

NodePath	get_vertex_space (int i, const NodePath &rel_to) const
	Returns the coordinate space of the nth control vertex of the curve, expressed as a NodePath. More...

void	get_vertices (Vert4Array &verts, const NodePath &rel_to) const

void	get_vertices (Vert3Array &verts, const NodePath &rel_to) const

void	normalize_knots ()
	Normalizes the knot sequence so that the parametric range of the curve is 0 More...

void	output (std::ostream &out) const

	PT (NurbsCurveResult) evaluate(const NodePath &rel_to

	PT (NurbsCurveResult) evaluate(const NodePath &rel_to

void	reset (int num_vertices)
	Resets all the vertices and knots to their default values, and sets the curve up with the indicated number of vertices. More...

void	set_extended_vertex (int i, int d, PN_stdfloat value)
	Sets an n-dimensional vertex value. More...

void	set_extended_vertices (int i, int d, const PN_stdfloat values[], int num_values)
	Simultaneously sets several extended values in the slots d through (d + num_values - 1) from the num_values elements of the indicated array. More...

void	set_knot (int i, PN_stdfloat knot)
	Sets the value of the nth knot. More...

void	set_order (int order)
	Sets the order of the curve. More...

void	set_vertex (int i, const LVecBase4 &vertex)
	Sets the nth control vertex of the curve, as a vertex in 4-d homogeneous space. More...

void	set_vertex (int i, const LVecBase3 &vertex, PN_stdfloat weight=1.0)
	Sets the nth control vertex of the curve. More...

void	set_vertex_space (int i, const NodePath &space)
	Sets the coordinate space of the nth control vertex. More...

void	set_vertex_space (int i, const std::string &space)
	Sets the coordinate space of the nth control vertex. More...

Public Member Functions inherited from ReferenceCount
int	get_ref_count () const

WeakReferenceList *	get_weak_list () const
	Returns the WeakReferenceList associated with this ReferenceCount object. More...

bool	has_weak_list () const
	Returns true if this particular ReferenceCount object has a WeakReferenceList created, false otherwise. More...

void	local_object ()
	This function should be called, once, immediately after creating a new instance of some ReferenceCount-derived object on the stack. More...

void	ref () const
	Explicitly increments the reference count. More...

bool	ref_if_nonzero () const
	Atomically increases the reference count of this object if it is not zero. More...

bool	test_ref_count_integrity () const
	Does some easy checks to make sure that the reference count isn't completely bogus. More...

bool	test_ref_count_nonzero () const
	Does some easy checks to make sure that the reference count isn't zero, or completely bogus. More...

virtual bool	unref () const
	Explicitly decrements the reference count. More...

WeakReferenceList *	weak_ref ()
	Adds the indicated PointerToVoid as a weak reference to this object. More...

void	weak_unref ()
	Removes the indicated PointerToVoid as a weak reference to this object. More...

Public Attributes
const LMatrix4 &mat	const

	get_knot
	Returns the value of the nth knot. More...

	get_num_knots
	Returns the number of knot values in the curve. More...

	get_num_vertices
	Returns the number of control vertices in the curve. More...

	get_vertex
	Returns the nth control vertex of the curve, relative to its indicated coordinate space. More...

Public Attributes inherited from ReferenceCount
	get_ref_count
	Returns the current reference count. More...

Additional Inherited Members
Static Public Member Functions inherited from ReferenceCount
static TypeHandle	get_class_type ()

static void	init_type ()

Detailed Description

This class is an abstraction for evaluating NURBS curves.

It accepts an array of vertices, each of which may be in a different coordinate space (as defined by a NodePath), as well as an optional knot vector.

This is not related to NurbsCurve, CubicCurveseg or any of the ParametricCurve-derived objects in this module. It is a completely parallel implementation of NURBS curves, and will probably eventually replace the whole ParametricCurve class hierarchy.

Definition at line 39 of file nurbsCurveEvaluator.h.

Member Function Documentation

◆ get_extended_vertex()

PN_stdfloat NurbsCurveEvaluator::get_extended_vertex	(	int	i,
		int	d
	)		const

inline

Returns an n-dimensional vertex value.

See set_extended_vertex(). This returns the value set for the indicated dimension, or 0.0 if nothing has been set.

Definition at line 152 of file nurbsCurveEvaluator.I.

◆ get_num_segments()

int NurbsCurveEvaluator::get_num_segments ( ) const

inline

Returns the number of piecewise continuous segments in the curve.

This is based on the knot vector.

Definition at line 171 of file nurbsCurveEvaluator.I.

References NurbsBasisVector::get_num_segments().

◆ get_order()

int NurbsCurveEvaluator::get_order ( ) const

inline

Returns the order of the curve as set by a previous call to set_order().

Definition at line 32 of file nurbsCurveEvaluator.I.

◆ get_vertex_space()

NodePath NurbsCurveEvaluator::get_vertex_space	(	int	i,
		const NodePath &	rel_to
	)		const

Returns the coordinate space of the nth control vertex of the curve, expressed as a NodePath.

Definition at line 55 of file nurbsCurveEvaluator.cxx.

◆ normalize_knots()

void NurbsCurveEvaluator::normalize_knots ( )

Normalizes the knot sequence so that the parametric range of the curve is 0

. 1.

Definition at line 110 of file nurbsCurveEvaluator.cxx.

References get_num_vertices.

◆ reset()

void NurbsCurveEvaluator::reset ( int num_vertices )

Resets all the vertices and knots to their default values, and sets the curve up with the indicated number of vertices.

You must then call set_vertex() repeatedly to fill in all of the vertex values appropriately.

Definition at line 39 of file nurbsCurveEvaluator.cxx.

◆ set_extended_vertex()

void NurbsCurveEvaluator::set_extended_vertex	(	int	i,
		int	d,
		PN_stdfloat	value
	)

inline

Sets an n-dimensional vertex value.

This allows definition of a NURBS surface or curve in a sparse n-dimensional space, typically used for associating additional properties (like color or joint membership) with each vertex of a surface.

The value d is an arbitrary integer value and specifies the dimension of question for this particular vertex. Any number of dimensions may be specified, and they need not be consecutive. If a value for a given dimension is not specified, is it implicitly 0.0.

The value is implicitly scaled by the homogenous weight value–that is, the fourth component of the value passed to set_vertex(). This means the ordinary vertex must be set first, before the extended vertices can be set.

Definition at line 141 of file nurbsCurveEvaluator.I.

◆ set_extended_vertices()

void NurbsCurveEvaluator::set_extended_vertices	(	int	i,
		int	d,
		const PN_stdfloat	values[],
		int	num_values
	)

Simultaneously sets several extended values in the slots d through (d + num_values - 1) from the num_values elements of the indicated array.

This is equivalent to calling set_extended_vertex() num_values times. See set_extended_vertex().

Definition at line 70 of file nurbsCurveEvaluator.cxx.

◆ set_knot()

void NurbsCurveEvaluator::set_knot	(	int	i,
		PN_stdfloat	knot
	)

Sets the value of the nth knot.

Each knot value should be greater than or equal to the preceding value. If no knot values are set, a default knot vector is supplied.

Definition at line 85 of file nurbsCurveEvaluator.cxx.

◆ set_order()

void NurbsCurveEvaluator::set_order ( int order )

inline

Sets the order of the curve.

This resets the knot vector to the default knot vector for the number of vertices.

The order must be 1, 2, 3, or 4, and the value is one more than the degree of the curve.

Definition at line 22 of file nurbsCurveEvaluator.I.

◆ set_vertex() [1/2]

void NurbsCurveEvaluator::set_vertex	(	int	i,
		const LVecBase4 &	vertex
	)

inline

Sets the nth control vertex of the curve, as a vertex in 4-d homogeneous space.

In this form, the first three components of the vertex should already have been scaled by the fourth component, which is the homogeneous weight.

Definition at line 52 of file nurbsCurveEvaluator.I.

◆ set_vertex() [2/2]

void NurbsCurveEvaluator::set_vertex	(	int	i,
		const LVecBase3 &	vertex,
		PN_stdfloat	weight = `1.0`
	)

inline

Sets the nth control vertex of the curve.

This flavor sets the vertex as a 3-d coordinate and a weight; the 3-d coordinate values are implicitly scaled up by the weight factor.

Definition at line 63 of file nurbsCurveEvaluator.I.

◆ set_vertex_space() [1/2]

void NurbsCurveEvaluator::set_vertex_space	(	int	i,
		const NodePath &	space
	)

inline

Sets the coordinate space of the nth control vertex.

If this is not specified, or is set to an empty NodePath, the nth control vertex is deemed to be in the coordinate space passed to evaluate().

This specifies the space as a fixed NodePath, which is always the same NodePath. Also see setting the space as a path string, which can specify a different NodePath for different instances of the curve.

Definition at line 106 of file nurbsCurveEvaluator.I.

◆ set_vertex_space() [2/2]

void NurbsCurveEvaluator::set_vertex_space	(	int	i,
		const std::string &	space
	)

inline

Sets the coordinate space of the nth control vertex.

If this is not specified, or is set to an empty string, the nth control vertex is deemed to be in the coordinate space passed to evaluate().

This specifies the space as a string, which describes the path to find the node relative to the rel_to NodePath when the curve is evaluated.

Definition at line 120 of file nurbsCurveEvaluator.I.

Member Data Documentation

◆ get_knot

PN_stdfloat NurbsCurveEvaluator::get_knot

Returns the value of the nth knot.

Definition at line 68 of file nurbsCurveEvaluator.h.

◆ get_num_knots

int NurbsCurveEvaluator::get_num_knots

inline

Returns the number of knot values in the curve.

This is based on the number of vertices and the order.

Definition at line 68 of file nurbsCurveEvaluator.h.

◆ get_num_vertices

int NurbsCurveEvaluator::get_num_vertices

inline

Returns the number of control vertices in the curve.

This is the number passed to the last call to reset().

Definition at line 54 of file nurbsCurveEvaluator.h.

Referenced by normalize_knots().

◆ get_vertex

LVecBase4 NurbsCurveEvaluator::get_vertex

inline

Returns the nth control vertex of the curve, relative to its indicated coordinate space.

Returns the nth control vertex of the curve, relative to the given coordinate space.

Definition at line 54 of file nurbsCurveEvaluator.h.

The documentation for this class was generated from the following files:

panda/src/parametrics/nurbsCurveEvaluator.h
panda/src/parametrics/nurbsCurveEvaluator.cxx
panda/src/parametrics/nurbsCurveEvaluator.I

Public Types

Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ get_extended_vertex()

◆ get_num_segments()

◆ get_order()

◆ get_vertex_space()

◆ normalize_knots()

◆ reset()

◆ set_extended_vertex()

◆ set_extended_vertices()

◆ set_knot()

◆ set_order()

◆ set_vertex() [1/2]

◆ set_vertex() [2/2]

◆ set_vertex_space() [1/2]

◆ set_vertex_space() [2/2]

Member Data Documentation

◆ get_knot

◆ get_num_knots

◆ get_num_vertices

◆ get_vertex