man A Map to translate between layout (3): screen and paint device metrics.

Other Alias

QwtMetricsMap

SYNOPSIS

#include <qwt_layout_metrics.h>

Public Member Functions

QPoint deviceToLayout (const QPoint &, const QPainter *=NULL) const

QSize deviceToLayout (const QSize &) const

QRect deviceToLayout (const QRect &, const QPainter *=NULL) const

QwtPolygon deviceToLayout (const QwtPolygon &, const QPainter *=NULL) const

int deviceToLayoutX (int x) const

int deviceToLayoutY (int y) const

bool isIdentity () const

QSize layoutToDevice (const QSize &) const

QwtPolygon layoutToDevice (const QwtPolygon &, const QPainter *=NULL) const

QRect layoutToDevice (const QRect &, const QPainter *=NULL) const

QPoint layoutToDevice (const QPoint &, const QPainter *=NULL) const

int layoutToDeviceX (int x) const

int layoutToDeviceY (int y) const

QSize layoutToScreen (const QSize &) const

QRect layoutToScreen (const QRect &) const

QPoint layoutToScreen (const QPoint &point) const

int layoutToScreenX (int x) const

int layoutToScreenY (int y) const

QPoint screenToLayout (const QPoint &) const

QRect screenToLayout (const QRect &) const

QSize screenToLayout (const QSize &) const

int screenToLayoutX (int x) const

int screenToLayoutY (int y) const

void setMetrics (const QPaintDevice *layoutMetrics, const QPaintDevice *deviceMetrics)

Static Public Member Functions

static QwtPolygon translate (const QMatrix &, const QwtPolygon &)

static QRect translate (const QMatrix &, const QRect &)

Detailed Description

A Map to translate between layout, screen and paint device metrics.

Qt3 supports painting in integer coordinates only. Therefore it is not possible to scale the layout in screen coordinates to layouts in higher resolutions ( f.e printing ) without losing the higher precision. QwtMetricsMap is used to incorporate the various widget attributes ( always in screen resolution ) into the layout/printing code of QwtPlot.

Qt4 is able to paint floating point based coordinates, what makes it possible always to render in screen coordinates ( with a common scale factor ). QwtMetricsMap will be obsolete as soon as Qt3 support has been dropped ( Qwt 6.x ).

Member Function Documentation

QwtPolygon QwtMetricsMap::translate (const QMatrix &m, const QwtPolygon &pa) [static]Wrapper for QMatrix::map.

Parameters:

: m Matrix
pa Polygon to translate

Returns:

: Translated polygon

QRect QwtMetricsMap::translate (const QMatrix &m, const QRect &rect) [static]Wrapper for QMatrix::mapRect.