ZoomTransition Class Reference

Perform calculations to determine the next zoom setting given the current zoom setting, when zooming in or out. More...

#include <ZoomTransition.h>

Collaboration diagram for ZoomTransition:

Public Member Functions
	ZoomTransition ()
	Single constructor. More...
double	mapToFactor (ZoomFactor zoomFactor) const
	Return the floating precision zoom factor given the enum value. More...
ZoomFactor	zoomIn (ZoomFactor currentZoomFactor, double m11, double m22, bool actionZoomFillIsChecked) const
	Zoom in. More...
ZoomFactor	zoomOut (ZoomFactor currentZoomFactor, double m11, double m22, bool actionZoomFillIsChecked) const
	Zoom out. More...

Detailed Description

Perform calculations to determine the next zoom setting given the current zoom setting, when zooming in or out.

Definition at line 13 of file ZoomTransition.h.

Constructor & Destructor Documentation

ZoomTransition()

ZoomTransition::ZoomTransition

(

)

Single constructor.

Definition at line 16 of file ZoomTransition.cpp.

{
  m_zoomMapToFactor [ZOOM_16_TO_1] = 16.0;
  m_zoomMapToFactor [ZOOM_16_TO_1_FARTHER] = 16.0 * FARTHER;
  m_zoomMapToFactor [ZOOM_8_TO_1_CLOSER] = 8.0 * CLOSER;
  m_zoomMapToFactor [ZOOM_8_TO_1] = 8.0;
  m_zoomMapToFactor [ZOOM_8_TO_1_FARTHER] = 8.0 * FARTHER;
  m_zoomMapToFactor [ZOOM_4_TO_1_CLOSER] = 4.0 * CLOSER;
  m_zoomMapToFactor [ZOOM_4_TO_1] = 4.0;
  m_zoomMapToFactor [ZOOM_4_TO_1_FARTHER] = 4.0 * FARTHER;
  m_zoomMapToFactor [ZOOM_2_TO_1_CLOSER] = 2.0 * CLOSER;
  m_zoomMapToFactor [ZOOM_2_TO_1] = 2.0;
  m_zoomMapToFactor [ZOOM_2_TO_1_FARTHER] = 2.0 * FARTHER;
  m_zoomMapToFactor [ZOOM_1_TO_1_CLOSER] = 1.0 * CLOSER;
  m_zoomMapToFactor [ZOOM_1_TO_1] = 1.0;
  m_zoomMapToFactor [ZOOM_1_TO_1_FARTHER] = 1.0 * FARTHER;
  m_zoomMapToFactor [ZOOM_1_TO_2_CLOSER] = 0.5 * CLOSER;
  m_zoomMapToFactor [ZOOM_1_TO_2] = 0.5;
  m_zoomMapToFactor [ZOOM_1_TO_2_FARTHER] = 0.5 * FARTHER;
  m_zoomMapToFactor [ZOOM_1_TO_4_CLOSER] = 0.25 * CLOSER;
  m_zoomMapToFactor [ZOOM_1_TO_4] = 0.25;
  m_zoomMapToFactor [ZOOM_1_TO_4_FARTHER] = 0.25 * FARTHER;
  m_zoomMapToFactor [ZOOM_1_TO_8_CLOSER] = 0.125 * CLOSER;
  m_zoomMapToFactor [ZOOM_1_TO_8] = 0.125;
  m_zoomMapToFactor [ZOOM_1_TO_8_FARTHER] = 0.125 * FARTHER;
  m_zoomMapToFactor [ZOOM_1_TO_16_CLOSER] = 0.0625 * CLOSER;
  m_zoomMapToFactor [ZOOM_1_TO_16] = 0.0625;  
}

Member Function Documentation

mapToFactor()

double ZoomTransition::mapToFactor

(

ZoomFactor

zoomFactor

)

const

Return the floating precision zoom factor given the enum value.

Definition at line 45 of file ZoomTransition.cpp.

{
  ENGAUGE_ASSERT (m_zoomMapToFactor.contains (zoomFactor));
 
  return m_zoomMapToFactor [zoomFactor];
}

zoomIn()

ZoomFactor ZoomTransition::zoomIn	(	ZoomFactor	currentZoomFactor,
		double	m11,
		double	m22,
		bool	actionZoomFillIsChecked
	)		const

Zoom in.

Definition at line 52 of file ZoomTransition.cpp.

{
  LOG4CPP_INFO_S ((*mainCat)) << "ZoomTransition::zoomIn";
 
  // Try to zoom in
  ZoomFactor zoomFactorOld = currentZoomFactor;
 
  if (actionZoomFillIsChecked) {
 
    // Zooming in means user probably wants the more squished direction to be zoomed in by one step.
    // Loop through the zoom values until a match is found
    double xScale = m11;
    double yScale = m22;
    double scale = qMin(xScale, yScale); // Fit so large extent just fits
 
    for (int zoom = ZOOM_1_TO_16_CLOSER; zoom >= 0; zoom--) {
      ZoomFactor zoomFactor = static_cast<ZoomFactor> (zoom);
      if (scale < m_zoomMapToFactor [zoomFactor]) {
        zoomFactorOld = zoomFactor;
        break;
      }
    }
  }
 
  ZoomFactor zoomFactorNew = ZOOM_16_TO_1;
  if (zoomFactorOld > ZOOM_16_TO_1) {
    zoomFactorNew = static_cast<ZoomFactor> (zoomFactorOld - 1);
  }
 
  return zoomFactorNew;
}

zoomOut()

ZoomFactor ZoomTransition::zoomOut	(	ZoomFactor	currentZoomFactor,
		double	m11,
		double	m22,
		bool	actionZoomFillIsChecked
	)		const

Zoom out.

Definition at line 87 of file ZoomTransition.cpp.

{
  LOG4CPP_INFO_S ((*mainCat)) << "ZoomTransition::zoomOut";
 
  // Try to zoom out
  ZoomFactor zoomFactorOld = currentZoomFactor;
 
  if (actionZoomFillIsChecked) {
 
    // Zooming out means user probably wants the less squished direction to be zoomed out by one step.
    // Loop through the zoom values until a match is found
    double xScale = m11;
    double yScale = m22;
    double scale = qMax(xScale, yScale); // Fit so larger extent just fits
 
    for (int zoom = 0; zoom <= ZOOM_1_TO_16_CLOSER; zoom++) {
      ZoomFactor zoomFactor = static_cast<ZoomFactor> (zoom);
      if (scale > m_zoomMapToFactor [zoomFactor]) {
        zoomFactorOld = zoomFactor;
        break;
      }
    }
  }
 
  ZoomFactor zoomFactorNew = ZOOM_1_TO_16;
  if (zoomFactorOld < ZOOM_1_TO_16) {
    zoomFactorNew = static_cast<ZoomFactor> (zoomFactorOld + 1);
  }
 
  return zoomFactorNew;
}

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

• Zoom/ZoomTransition.h
• Zoom/ZoomTransition.cpp