StandardConstValueAccessor< VALUETYPE > Class Template Reference

Encapsulate access to the values an iterator points to. More...

#include <vigra/accessor.hxx>

Public Member Functions
template<class ITERATOR >
VALUETYPE	operator() (ITERATOR const &i) const
template<class ITERATOR , class OFFSET >
VALUETYPE	operator() (ITERATOR const &i, OFFSET const &diff) const

Detailed Description

template<class VALUETYPE>
class vigra::StandardConstValueAccessor< VALUETYPE >

Encapsulate access to the values an iterator points to.

StandardConstValueAccessor is a trivial accessor that simply encapsulates the iterator's operator*() and operator[]() in its read functions. It passes its arguments by value. If the iterator returns its items by reference (such as vigra::ConstImageIterator), you can also use StandardConstAccessor. These accessors have different optimization properties – StandardConstAccessor is usually faster for compound pixel types, while StandardConstValueAccessor is faster for the built-in types.

When an iterator passes a floating point number to an accessor with integral value_type, the value is rounded and clipped as appropriate.

#include <vigra/accessor.hxx>
Namespace: vigra

Member Function Documentation

VALUETYPE operator()

(

ITERATOR const &

i

)

const

Read the current data item. The type ITERATOR::reference is automatically converted to VALUETYPE. In case of a conversion floating point -> integral this includes rounding and clipping.

VALUETYPE operator()	(	ITERATOR const &	i,
		OFFSET const &	diff
	)		const

Read the data item at an offset (can be 1D or 2D or higher order difference). The type ITERATOR::index_reference is automatically converted to VALUETYPE. In case of a conversion floating point -> integral this includes rounding and clipping.

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

• vigra/accessor.hxx