ZoomConstraint Class Reference

#include <ZoomConstraint.h>

Inherited by PowerOfSqrtTwoZoomConstraint [virtual], and PowerOfTwoZoomConstraint [virtual].

Inheritance diagram for ZoomConstraint:

[legend]List of all members.

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Detailed Description

ZoomConstraint is a simple interface that describes a limitation on the available zoom sizes for a view, for example based on cache strategy or a (processing) window-size limitation.

The default ZoomConstraint imposes no actual constraint except for a nominal maximum.

Definition at line 30 of file ZoomConstraint.h.

Public Types
enum	RoundingDirection { RoundDown, RoundUp, RoundNearest }
Public Member Functions
virtual	~ZoomConstraint ()
virtual size_t	getNearestBlockSize (size_t requestedBlockSize, RoundingDirection=RoundNearest) const
	Given the "ideal" block size (frames per pixel) for a given zoom level, return the nearest viable block size for this constraint.
virtual size_t	getMaxZoomLevel () const
	Return the maximum zoom level within range for this constraint.

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Member Enumeration Documentation

enum ZoomConstraint::RoundingDirection

Enumerator:

RoundDown
RoundUp
RoundNearest

Definition at line 35 of file ZoomConstraint.h.

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Constructor & Destructor Documentation

virtual ZoomConstraint::~ZoomConstraint

(

)

[inline, virtual]

Definition at line 33 of file ZoomConstraint.h.

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Member Function Documentation

virtual size_t ZoomConstraint::getNearestBlockSize	(	size_t	requestedBlockSize,
		RoundingDirection	= RoundNearest
	)			const [inline, virtual]

Given the "ideal" block size (frames per pixel) for a given zoom level, return the nearest viable block size for this constraint.

For example, if a block size of 1523 frames per pixel is requested but the underlying model only supports value summaries at powers-of-two block sizes, return 1024 or 2048 depending on the rounding direction supplied.

Reimplemented in PowerOfSqrtTwoZoomConstraint, and PowerOfTwoZoomConstraint.

Definition at line 51 of file ZoomConstraint.h.

References getMaxZoomLevel().

virtual size_t ZoomConstraint::getMaxZoomLevel

(

)

const [inline, virtual]

Return the maximum zoom level within range for this constraint.

Definition at line 62 of file ZoomConstraint.h.

Referenced by getNearestBlockSize(), PowerOfTwoZoomConstraint::getNearestBlockSize(), and PowerOfSqrtTwoZoomConstraint::getNearestBlockSize().

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

• ZoomConstraint.h

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