QGIS API Documentation  3.11.0-Master (68611307d7)
Static Public Member Functions | Friends | List of all members
QgsLayoutUtils Class Reference

Utilities for layouts. More...

#include <qgslayoututils.h>

Static Public Member Functions

static double calculatePrettySize (double minimumSize, double maximumSize)
 Calculates a "pretty" size which falls between the range [minimumSize, maximumSize]. More...
 
static QgsRenderContext createRenderContextForLayout (QgsLayout *layout, QPainter *painter, double dpi=-1)
 Creates a render context suitable for the specified layout and painter destination. More...
 
static QgsRenderContext createRenderContextForMap (QgsLayoutItemMap *map, QPainter *painter, double dpi=-1)
 Creates a render context suitable for the specified layout map and painter destination. More...
 
static QgsLayoutItemPage::Orientation decodePaperOrientation (const QString &string, bool &ok)
 Decodes a string representing a paper orientation and returns the decoded orientation. More...
 
static void drawText (QPainter *painter, QPointF position, const QString &text, const QFont &font, const QColor &color=QColor())
 Draws text on a painter at a specific position, taking care of layout specific issues (calculation to pixel, scaling of font and painter to work around Qt font bugs). More...
 
static void drawText (QPainter *painter, const QRectF &rectangle, const QString &text, const QFont &font, const QColor &color=QColor(), Qt::AlignmentFlag halignment=Qt::AlignLeft, Qt::AlignmentFlag valignment=Qt::AlignTop, int flags=Qt::TextWordWrap)
 Draws text on a painter within a rectangle, taking care of layout specific issues (calculation to pixel, scaling of font and painter to work around Qt font bugs). More...
 
static double fontAscentMM (const QFont &font)
 Calculates a font ascent in millimeters, including workarounds for QT font rendering issues. More...
 
static double fontDescentMM (const QFont &font)
 Calculate a font descent in millimeters, including workarounds for QT font rendering issues. More...
 
static double fontHeightCharacterMM (const QFont &font, QChar character)
 Calculate a font height in millimeters of a single character, including workarounds for QT font rendering issues. More...
 
static double fontHeightMM (const QFont &font)
 Calculate a font height in millimeters, including workarounds for QT font rendering issues. More...
 
static QRectF largestRotatedRectWithinBounds (const QRectF &originalRect, const QRectF &boundsRect, double rotation)
 Calculates the largest scaled version of originalRect which fits within boundsRect, when it is rotated by the a specified rotation amount. More...
 
static QgsMapLayermapLayerFromString (const QString &string, QgsProject *project)
 Resolves a string into a map layer from a given project. More...
 
static double normalizedAngle (double angle, bool allowNegative=false)
 Ensures that an angle (in degrees) is in the range 0 <= angle < 360. More...
 
static double relativePosition (double position, double beforeMin, double beforeMax, double afterMin, double afterMax)
 Returns a scaled position given a before and after range. More...
 
static void relativeResizeRect (QRectF &rectToResize, const QRectF &boundsBefore, const QRectF &boundsAfter)
 Resizes a QRectF relative to a resized bounding rectangle. More...
 
static void rotate (double angle, double &x, double &y)
 Rotates a point / vector around the origin. More...
 
static QFont scaledFontPixelSize (const QFont &font)
 Returns a font where size is set in points and the size has been upscaled with FONT_WORKAROUND_SCALE to workaround QT font rendering bugs. More...
 
static double scaleFactorFromItemStyle (const QStyleOptionGraphicsItem *style)
 Extracts the scale factor from an item style. More...
 
static double snappedAngle (double angle)
 Snaps an angle (in degrees) to its closest 45 degree angle. More...
 
static double textHeightMM (const QFont &font, const QString &text, double multiLineHeight=1.0)
 Calculate a font height in millimeters for a text string, including workarounds for QT font rendering issues. More...
 
static double textWidthMM (const QFont &font, const QString &text)
 Calculate a font width in millimeters for a text string, including workarounds for QT font rendering issues. More...
 

Friends

class TestQgsLayoutUtils
 

Detailed Description

Utilities for layouts.

Since
QGIS 3.0

Definition at line 37 of file qgslayoututils.h.

Member Function Documentation

◆ calculatePrettySize()

double QgsLayoutUtils::calculatePrettySize ( double  minimumSize,
double  maximumSize 
)
static

Calculates a "pretty" size which falls between the range [minimumSize, maximumSize].

This method will return an optimal round number which falls within the given range, finding the largest "pretty" number possible.

Since
QGIS 3.10

Definition at line 438 of file qgslayoututils.cpp.

◆ createRenderContextForLayout()

QgsRenderContext QgsLayoutUtils::createRenderContextForLayout ( QgsLayout layout,
QPainter *  painter,
double  dpi = -1 
)
static

Creates a render context suitable for the specified layout and painter destination.

This method returns a new QgsRenderContext which matches the scale and settings from the layout's QgsLayout::referenceMap(). If the dpi argument is not specified then the dpi will be taken from the destination painter device.

See also
createRenderContextForMap()

Definition at line 138 of file qgslayoututils.cpp.

◆ createRenderContextForMap()

QgsRenderContext QgsLayoutUtils::createRenderContextForMap ( QgsLayoutItemMap map,
QPainter *  painter,
double  dpi = -1 
)
static

Creates a render context suitable for the specified layout map and painter destination.

This method returns a new QgsRenderContext which matches the scale and settings of the target map. If the dpi argument is not specified then the dpi will be taken from the destination painter device.

See also
createRenderContextForLayout()

Definition at line 94 of file qgslayoututils.cpp.

◆ decodePaperOrientation()

QgsLayoutItemPage::Orientation QgsLayoutUtils::decodePaperOrientation ( const QString &  string,
bool &  ok 
)
static

Decodes a string representing a paper orientation and returns the decoded orientation.

If the string was correctly decoded, ok will be set to true.

Definition at line 373 of file qgslayoututils.cpp.

◆ drawText() [1/2]

void QgsLayoutUtils::drawText ( QPainter *  painter,
QPointF  position,
const QString &  text,
const QFont &  font,
const QColor &  color = QColor() 
)
static

Draws text on a painter at a specific position, taking care of layout specific issues (calculation to pixel, scaling of font and painter to work around Qt font bugs).

If color is specified, text will be rendered in that color. If not specified, the current painter pen color will be used instead.

Definition at line 244 of file qgslayoututils.cpp.

◆ drawText() [2/2]

void QgsLayoutUtils::drawText ( QPainter *  painter,
const QRectF &  rectangle,
const QString &  text,
const QFont &  font,
const QColor &  color = QColor(),
Qt::AlignmentFlag  halignment = Qt::AlignLeft,
Qt::AlignmentFlag  valignment = Qt::AlignTop,
int  flags = Qt::TextWordWrap 
)
static

Draws text on a painter within a rectangle, taking care of layout specific issues (calculation to pixel, scaling of font and painter to work around Qt font bugs).

If color is specified, text will be rendered in that color. If not specified, the current painter pen color will be used instead.

The text alignment within rectangle can be set via the halignment and valignment arguments.

The flags parameter allows for passing Qt::TextFlags to control appearance of rendered text.

Definition at line 267 of file qgslayoututils.cpp.

◆ fontAscentMM()

double QgsLayoutUtils::fontAscentMM ( const QFont &  font)
static

Calculates a font ascent in millimeters, including workarounds for QT font rendering issues.

See also
fontDescentMM()
fontHeightMM()
fontHeightCharacterMM()
textWidthMM()

Definition at line 181 of file qgslayoututils.cpp.

◆ fontDescentMM()

double QgsLayoutUtils::fontDescentMM ( const QFont &  font)
static

Calculate a font descent in millimeters, including workarounds for QT font rendering issues.

See also
fontAscentMM()
fontHeightMM()
fontHeightCharacterMM()
textWidthMM()

Definition at line 190 of file qgslayoututils.cpp.

◆ fontHeightCharacterMM()

double QgsLayoutUtils::fontHeightCharacterMM ( const QFont &  font,
QChar  character 
)
static

Calculate a font height in millimeters of a single character, including workarounds for QT font rendering issues.

See also
fontAscentMM()
fontDescentMM()
fontHeightMM()
textWidthMM()

Definition at line 210 of file qgslayoututils.cpp.

◆ fontHeightMM()

double QgsLayoutUtils::fontHeightMM ( const QFont &  font)
static

Calculate a font height in millimeters, including workarounds for QT font rendering issues.

The font height is the font ascent + descent + 1 (for the baseline).

See also
fontAscentMM()
fontDescentMM()
fontHeightCharacterMM()
textWidthMM()

Definition at line 200 of file qgslayoututils.cpp.

◆ largestRotatedRectWithinBounds()

QRectF QgsLayoutUtils::largestRotatedRectWithinBounds ( const QRectF &  originalRect,
const QRectF &  boundsRect,
double  rotation 
)
static

Calculates the largest scaled version of originalRect which fits within boundsRect, when it is rotated by the a specified rotation amount.

Parameters
originalRectQRectF to be rotated and scaled
boundsRectQRectF specifying the bounds which the rotated and scaled rectangle must fit within
rotationthe rotation in degrees to be applied to the rectangle
Returns
largest scaled version of the rectangle possible

Definition at line 293 of file qgslayoututils.cpp.

◆ mapLayerFromString()

QgsMapLayer * QgsLayoutUtils::mapLayerFromString ( const QString &  string,
QgsProject project 
)
static

Resolves a string into a map layer from a given project.

Attempts different forms of layer matching such as matching by layer id or layer name.

Layer names are matched using a case-insensitive check, ONLY if an exact case match was not found.

Since
QGIS 3.2

Definition at line 403 of file qgslayoututils.cpp.

◆ normalizedAngle()

double QgsLayoutUtils::normalizedAngle ( double  angle,
bool  allowNegative = false 
)
static

Ensures that an angle (in degrees) is in the range 0 <= angle < 360.

If allowNegative is true then angles between (-360, 360) are allowed. If false, angles are converted to positive angles in the range [0, 360).

Definition at line 40 of file qgslayoututils.cpp.

◆ relativePosition()

double QgsLayoutUtils::relativePosition ( double  position,
double  beforeMin,
double  beforeMax,
double  afterMin,
double  afterMax 
)
static

Returns a scaled position given a before and after range.

Parameters
positioninitial position within before range to scale
beforeMinminimum value in before range
beforeMaxmaximum value in before range
afterMinminimum value in after range
afterMaxmaximum value in after range
Returns
position scaled to range specified by afterMin and afterMax

Definition at line 162 of file qgslayoututils.cpp.

◆ relativeResizeRect()

void QgsLayoutUtils::relativeResizeRect ( QRectF &  rectToResize,
const QRectF &  boundsBefore,
const QRectF &  boundsAfter 
)
static

Resizes a QRectF relative to a resized bounding rectangle.

Parameters
rectToResizeQRectF to resize, contained within boundsBefore. The rectangle is linearly scaled to retain its relative position and size within boundsAfter.
boundsBeforeQRectF of bounds before resize
boundsAfterQRectF of bounds after resize

Definition at line 151 of file qgslayoututils.cpp.

◆ rotate()

void QgsLayoutUtils::rotate ( double  angle,
double &  x,
double &  y 
)
static

Rotates a point / vector around the origin.

Parameters
anglerotation angle in degrees, counterclockwise
xin/out: x coordinate before / after the rotation
yin/out: y coordinate before / after the rotation

Definition at line 30 of file qgslayoututils.cpp.

◆ scaledFontPixelSize()

QFont QgsLayoutUtils::scaledFontPixelSize ( const QFont &  font)
static

Returns a font where size is set in points and the size has been upscaled with FONT_WORKAROUND_SCALE to workaround QT font rendering bugs.

Returns a font with size set in pixels.

Definition at line 171 of file qgslayoututils.cpp.

◆ scaleFactorFromItemStyle()

double QgsLayoutUtils::scaleFactorFromItemStyle ( const QStyleOptionGraphicsItem *  style)
static

Extracts the scale factor from an item style.

Definition at line 390 of file qgslayoututils.cpp.

◆ snappedAngle()

double QgsLayoutUtils::snappedAngle ( double  angle)
static

Snaps an angle (in degrees) to its closest 45 degree angle.

Returns
angle snapped to 0, 45/90/135/180/225/270 or 315 degrees

Definition at line 54 of file qgslayoututils.cpp.

◆ textHeightMM()

double QgsLayoutUtils::textHeightMM ( const QFont &  font,
const QString &  text,
double  multiLineHeight = 1.0 
)
static

Calculate a font height in millimeters for a text string, including workarounds for QT font rendering issues.

Note that this method uses a non-standard measure of text height, where only the font ascent is considered for the first line of text.

The multiLineHeight parameter specifies the line spacing factor.

See also
textWidthMM()

Definition at line 228 of file qgslayoututils.cpp.

◆ textWidthMM()

double QgsLayoutUtils::textWidthMM ( const QFont &  font,
const QString &  text 
)
static

Calculate a font width in millimeters for a text string, including workarounds for QT font rendering issues.

See also
fontAscentMM()
fontDescentMM()
fontHeightMM()
fontHeightCharacterMM()
textHeightMM()

Definition at line 219 of file qgslayoututils.cpp.

Friends And Related Function Documentation

◆ TestQgsLayoutUtils

friend class TestQgsLayoutUtils
friend

Definition at line 252 of file qgslayoututils.h.


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