This is like PixPath except that it has an arclength cache, for teh performance. More...

#include <ppath_ac.h>

Inheritance diagram for kjb::qd::PixPathAc:

Public Member Functions
	PixPathAc (const PixPath &path)
	ctor copies from a PixPath. This is the only public ctor. More...

PixPathAc &	assign (unsigned index, const PixPoint &newp)
	assign a location in a PixPathAc More...

void	swap (PixPathAc &vpp)
	swap representations of two PixPathAc objects More...

void	push_back (const PixPoint &pp)
	add a new point to the end of the path More...

void	clear ()
	throw away all points More...

PixPathAc &	append (const_iterator begin, const_iterator end)
	append range of another path to this More...

PixPathAc &	append (const PixPath &suffix)
	tack on a copy of a given path to the end of this path More...

int	append_no_overlap (const PixPath &suffix)
	see description of PixPath::append_no_overlap() More...

PixPathAc &	ow_reverse ()
	Reverse the order of this path, IN PLACE! More...

int	arclength (std::vector< float > *alvec) const
	compute polygonal path length along path, ret. vector of results. More...

float	arclength (size_t index) const
	Return the polygonal path length from front() to indexed point. More...

float	arclength () const
	Return the polygonal path length for this path, front() to back() More...

size_t	whereis_arclength_ratio (float) const
	Return index of PixPoint in path at a given arclength ratio. More...

size_t	halfway () const
	Return index of PixPoint closest to but not beyond mid-arclength. More...

Public Member Functions inherited from kjb::qd::PixPath
virtual	~PixPath ()
	obligatory dtor More...

const PixPoint &	operator[] (unsigned index) const
	Vector-like access to points (returning an rvalue). More...

virtual void	pop_back ()

size_t	size () const
	Number of points in the path (not the same as its length). More...

virtual void	swap (PixPath &vpp)
	Swap the contents of two PixPaths. More...

const_iterator	begin () const
	Return an iterator pointing to the first point in the path. More...

const_iterator	end () const
	Rtn iterator pointing to just beyond the last point in the path. More...

const_reverse_iterator	rbegin () const
	return a reverse-moving iterator to the last point in path More...

const_reverse_iterator	rend () const
	return one-before-first iterator, in symmetry with end(). More...

PixPath	subrange (unsigned, unsigned) const
	Returns a subrange of this PixPath object. More...

PixPath	prefix (unsigned postlast) const
	Variation on subrange: return a prefix of this path (by value) More...

PixPath	suffix (unsigned first) const
	Variation on subrange: return a suffix of this path (by value) More...

bool	self_intersect (PixPoint *where=00) const
	Reveal whether the path has any self-intersections. More...

bool	connected8 (bool emit_verbose_debug_output=false) const
	Is the path all connected, using 8-connectivity? More...

PixPoint	front () const
	Return (by value) the first point in the path. More...

PixPoint	back () const
	Return (by value) the last point in the path. More...

std::string	str (const std::string &separator="\n") const
	Return the path as an ASCII string. More...

int	save (const std::string &filename) const
	Saves the path to an ASCII file, returns NO_ERROR or ERROR. More...

bool	operator== (const PixPath &) const
	Compare PixPaths; true iff the sequence of points is identical. More...

bool	operator!= (const PixPath &other) const
	Compare PixPaths; true iff the sequence of points differs. More...

PixPath	operator+ (const PixPath &) const
	Add, element-by-element, two PixPaths of the same length. More...

virtual PixPoint	boundbox_min_min () const
	Return the corner point of a bounding box, with min x and y. More...

virtual PixPoint	boundbox_max_max () const
	Similar to boundbox_min_min() but returns maximum x, y coords. More...

bool	boundbox_within_boundbox (const PixPath &outer) const
	Test whether the axis-aligned bounding box of this path lies within the axis-aligned bounding box of the given path. More...

bool	so_boundbox_holds_within (const PixPoint &q) const
	sort of like boundbox_within_boundbox but works on a single point More...

unsigned	hits (const PixPoint &query_point) const
	Return number of times (maybe 0) the path hits a query point. More...

unsigned	hits (const PixPath &query_path) const
	return number of common points between query_path and this path More...

PixPoint	nearest (const PixPoint &, const_iterator *q=00) const
	Return the PixPath member closest to a given query point. More...

PixPoint	nearest (const kjb::Vector2 &, const_iterator *q=00) const
	Return the PixPath member closest to the given real xy coordinates. More...

PixPath &	ow_reverse ()
	Reverse the order of the points in the path (overwriting!) More...

PixPath	reverse () const
	return a copy of this list after reversing the front-back order. More...

int	cubic_fit (std::vector< float > x, std::vector< float > y, int ref=0) const
	Fit a cubic polynomial to the given list of x and y points. More...

PixPath	interpolate (bool forbid_self_intersection=false) const
	This interpolates pixels between unconnected pixels. More...

PixPath	cull_redundant_points () const
	Remove "unnecessary" points (ones that can be bresenham interpolated) More...

PixPath	merge_redundant_slopes () const
	return a path with interior points removed but preserve all slopes. More...

PixPath	expel (const_iterator) const
	Duplicate this path, except that we omit the indicated point. More...

PixPath	expel (size_t index_of_unwanted_point) const
	Duplicate this path, except we omit the point with given index. More...

virtual float	hausdorff_distance (const PixPath &that) const
	Compute the Hausdorff metric between two sets of points. More...

float	closest_pair (const_iterator pa=0, const_iterator pb=0) const
	Find the distance between closest pair of points, ignoring adjacency. More...

float	closest_adjacent_pair (const_iterator *pa=0) const
	Find a pair of adjacent points at least as close as any other. More...

bool	has_subsequence (const PixPath &subseq) const
	tests whether a given path is a subsequence of this path More...

double	angle_at (unsigned) const
	Compute included angle at some interior point in a path. More...

PixPoint::Integer	bracket_cross_at (unsigned index) const
	cross product of line segs (index-1,index+1) x (index,index+1) More...

double	heading_shift_at (unsigned index) const
	compute shift in "heading" angle at an interior point More...

bool	intersect_at_with (unsigned preindex1, unsigned preindex2, unsigned *endpoint_intersector_index=00) const
	Test whether two segments of this path intersect. More...

bool	do_segments_intersect (unsigned s1=00, unsigned s2=00, unsigned *count=00) const
	quadratic time test whether any 2 path segments cross each other More...

unsigned	longest_segment (float *length=00) const
	return index of first point of longest segment More...

kjb::Vector2	centroid () const
	return the "mean" of the points (nonempty, none may be unused) More...

unsigned	member_near_centroid () const
	return index of a member point nearest centroid() (qv) More...

Static Public Member Functions
static PixPathAc	reserve (size_t potential_size=0)
	named ctor creates an empty path but reserves some memory for it More...

Static Public Member Functions inherited from kjb::qd::PixPath
static PixPath	reserve (size_t potential_size=0)
	named ctor creates an empty path but reserves some memory for it More...

static PixPath	load (const std::string &filename)
	named ctor loads path coordinates from an ASCII file More...

static PixPath	fenceposts (const PixPoint &pt_a, const PixPoint &pt_b, size_t sz)
	named ctor makes a path of evenly spaced points from a to b More...

static PixPath	parse (const std::string &coords)
	named ctor builds from string-format list of coordinates More...

Protected Member Functions
	PixPathAc ()
	default ctor almost the same as the PixPath default ctor More...

	PixPathAc (size_t potential_size)
	ctor receives the size to reserve More...

	PixPathAc (const std::string &fn)
	ctor loads from a file, just like PixPath ctor More...

Protected Member Functions inherited from kjb::qd::PixPath
	PixPath ()
	Default ctor starts as empty, and you can push points onto it. More...

	PixPath (size_t potential_size)
	ctor receives the size to reserve More...

	PixPath (const std::string &)
	ctor to load from an ASCII file More...

	PixPath (const PixPoint &, const PixPoint &, size_t)
	ctor makes evenly spaced points between termini More...

	PixPath (const std::string &, int)
	ctor that parses a string of characters More...

Additional Inherited Members
Public Types inherited from kjb::qd::PixPath
typedef const PixPoint &	const_reference
	Reference to an element – required to use std::back_inserter(). More...

typedef PixPoint	value_type
	Element type – required to use std::back_inserter() in c++11. More...

typedef VecPP::const_iterator	const_iterator
	constant iterator through PixPath points More...

typedef VecPP::const_reverse_iterator	const_reverse_iterator
	constant reverse iterator through PixPath points More...

Detailed Description

This is like PixPath except that it has an arclength cache, for teh performance.

Constructor & Destructor Documentation

kjb::qd::PixPathAc::PixPathAc ( )

inlineprotected

default ctor almost the same as the PixPath default ctor

kjb::qd::PixPathAc::PixPathAc ( size_t potential_size )

inlineprotected

ctor receives the size to reserve

kjb::qd::PixPathAc::PixPathAc ( const std::string & fn )

inlineprotected

ctor loads from a file, just like PixPath ctor

kjb::qd::PixPathAc::PixPathAc ( const PixPath & path )

inline

ctor copies from a PixPath. This is the only public ctor.

Member Function Documentation

PixPathAc& kjb::qd::PixPathAc::append	(	const_iterator	begin,
		const_iterator	end
	)

inlinevirtual

append range of another path to this

Reimplemented from kjb::qd::PixPath.

PixPathAc& kjb::qd::PixPathAc::append ( const PixPath & suffix )

inlinevirtual

tack on a copy of a given path to the end of this path

Parameters

suffix path to be concatenated

Returns: reference to this path after the update

Reimplemented from kjb::qd::PixPath.

int kjb::qd::PixPathAc::append_no_overlap ( const PixPath & suffix )

inlinevirtual

see description of PixPath::append_no_overlap()

Reimplemented from kjb::qd::PixPath.

int kjb::qd::PixPathAc::arclength ( std::vector< float > * alvec ) const

inlinevirtual

compute polygonal path length along path, ret. vector of results.

There is little use for this method, but it is here for completeness. Instead you probably should use method arclength( size_t ) const.

Parameters

alvec Pointer to vector of floats into which we return the cumulative polygonal path lengths from start to each vertex

Returns: kjb_c::ERROR or kjb_c::NO_ERROR as appropriate

Reimplemented from kjb::qd::PixPath.

float kjb::qd::PixPathAc::arclength ( size_t index ) const

inline

Return the polygonal path length from front() to indexed point.

Parameters

index index of vector at which to compute polygonal path length.

Returns: Polygonal path length computed as summed Euclidean distances.

This method makes the previous one sort of obsolete. I recommend you use this method.

float kjb::qd::PixPathAc::arclength ( ) const

virtual

Return the polygonal path length for this path, front() to back()

Reimplemented from kjb::qd::PixPath.

PixPathAc& kjb::qd::PixPathAc::assign	(	unsigned	index,
		const PixPoint &	newp
	)

inlinevirtual

assign a location in a PixPathAc

Reimplemented from kjb::qd::PixPath.

void kjb::qd::PixPathAc::clear ( )

inlinevirtual

throw away all points

Reimplemented from kjb::qd::PixPath.

size_t kjb::qd::PixPathAc::halfway ( ) const

inline

Return index of PixPoint closest to but not beyond mid-arclength.

PixPathAc& kjb::qd::PixPathAc::ow_reverse ( )

inline

Reverse the order of this path, IN PLACE!

void kjb::qd::PixPathAc::push_back ( const PixPoint & pp )

inlinevirtual

add a new point to the end of the path

Reimplemented from kjb::qd::PixPath.

static PixPathAc kjb::qd::PixPathAc::reserve ( size_t potential_size = 0 )

inlinestatic

named ctor creates an empty path but reserves some memory for it

void kjb::qd::PixPathAc::swap ( PixPathAc & vpp )

inline

swap representations of two PixPathAc objects

size_t kjb::qd::PixPathAc::whereis_arclength_ratio ( float rat ) const

Return index of PixPoint in path at a given arclength ratio.

Parameters

rat Ratio of two polygonal path lengths. The denominator is the path length of whole path. The numerator is the path length from the path front to the index of the vertex to be returned, if that vertex exists. If it does not exist, then there must be a vertex "before" and "after" the desired point, and we return the index of the one "before," i.e., closer to the front. Confusing? Example: if rat=0.5 then you get the index of the vertex at halfway or nearest halfway without going over halfway. If the ratio is more than one, we return the index of the last point. One exception to the above description: If the ratio is not positive, we return the index of the front point.

The actual arclength at that point is at most the given value: it is the "floor" of possible arclength ratios. This has to search the path for the desired ratio. If the arclength is already memoized, it takes time O(log N) where N is the path size. If the arclength is not memoized, it takes time O(N).

Returns: index of the vertex as described above.

Exceptions

Too_small if the path has no vertices

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

/work/kobus/src/lib/qd_cpp/ppath_ac.h
/work/kobus/src/lib/qd_cpp/ppath_ac.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation