vgl_region_scan_iterator Class Reference

#include <vgl_region_scan_iterator.h>

Inheritance diagram for vgl_region_scan_iterator:

[legend]List of all members.

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Detailed Description

Abstract base class for iterating over the pixels in a region of an image.

The region should be "scanline-convex", i.e., every horizontal line should intersect the region in at most one connected part. Vertically, there may be even disconnected parts: e.g. (part of) a hyperbola with vertical axis. The region should of course be bounded, otherwise iteration makes no sense.

Definition at line 17 of file vgl_region_scan_iterator.h.

Public Member Functions
virtual void	reset ()=0
	Resets the scan iterator to before the first scan line.
virtual bool	next ()=0
	Tries to move to the next scan line.
virtual int	scany () const =0
	y-coordinate of the current scan line.
virtual int	startx () const =0
	Returns starting x-value of the current scan line.
virtual int	endx () const =0
	Returns ending x-value of the current scan line.
int	count ()
	Number of image points (= integer grid points) inside the region.
Protected Member Functions
	vgl_region_scan_iterator ()
virtual	~vgl_region_scan_iterator ()

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Constructor & Destructor Documentation

vgl_region_scan_iterator::vgl_region_scan_iterator (   )  [inline, protected]

Definition at line 20 of file vgl_region_scan_iterator.h.

virtual vgl_region_scan_iterator::~vgl_region_scan_iterator (   )  [inline, protected, virtual]

Definition at line 21 of file vgl_region_scan_iterator.h.

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Member Function Documentation

int vgl_region_scan_iterator::count (   )  [inline]

Number of image points (= integer grid points) inside the region. Definition at line 48 of file vgl_region_scan_iterator.h.

virtual int vgl_region_scan_iterator::endx (   )  const [pure virtual]

Returns ending x-value of the current scan line. endx() should be larger than startx(), unless the scan line is empty Implemented in vgl_ellipse_scan_iterator< T >, vgl_polygon_scan_iterator< T >, vgl_triangle_scan_iterator< T >, and vgl_window_scan_iterator< T >.

virtual bool vgl_region_scan_iterator::next (   )  [pure virtual]

Tries to move to the next scan line. Returns false if there are no more scan lines. Implemented in vgl_ellipse_scan_iterator< T >, vgl_polygon_scan_iterator< T >, vgl_triangle_scan_iterator< T >, and vgl_window_scan_iterator< T >.

virtual void vgl_region_scan_iterator::reset (   )  [pure virtual]

Resets the scan iterator to before the first scan line. After calling this function, next() needs to be called before startx() and endx() form a valid scan line. Implemented in vgl_ellipse_scan_iterator< T >, vgl_polygon_scan_iterator< T >, vgl_triangle_scan_iterator< T >, and vgl_window_scan_iterator< T >.

virtual int vgl_region_scan_iterator::scany (   )  const [pure virtual]

y-coordinate of the current scan line. The next scan line is *not* guaranteed to have scany()+1; use next() instead. Implemented in vgl_ellipse_scan_iterator< T >, vgl_polygon_scan_iterator< T >, vgl_triangle_scan_iterator< T >, and vgl_window_scan_iterator< T >.

virtual int vgl_region_scan_iterator::startx (   )  const [pure virtual]

Returns starting x-value of the current scan line. startx() should be smaller than endx(), unless the scan line is empty Implemented in vgl_ellipse_scan_iterator< T >, vgl_polygon_scan_iterator< T >, vgl_triangle_scan_iterator< T >, and vgl_window_scan_iterator< T >.

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

• core/vgl/vgl_region_scan_iterator.h

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