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-rw-r--r--examples/widgets/doc/src/tablet.qdoc13
-rw-r--r--examples/widgets/graphicsview/collidingmice/mouse.cpp10
-rw-r--r--examples/widgets/graphicsview/diagramscene/arrow.cpp6
-rw-r--r--examples/widgets/graphicsview/elasticnodes/edge.cpp7
-rw-r--r--examples/widgets/itemviews/chart/pieview.cpp6
-rw-r--r--examples/widgets/mainwindows/mainwindow/mainwindow.cpp1
-rw-r--r--examples/widgets/widgets/tablet/tabletcanvas.cpp52
-rw-r--r--examples/widgets/widgets/tablet/tabletcanvas.h2
8 files changed, 54 insertions, 43 deletions
diff --git a/examples/widgets/doc/src/tablet.qdoc b/examples/widgets/doc/src/tablet.qdoc
index 88fdefa68f..2b11020c07 100644
--- a/examples/widgets/doc/src/tablet.qdoc
+++ b/examples/widgets/doc/src/tablet.qdoc
@@ -206,8 +206,7 @@
\snippet widgets/tablet/tabletcanvas.cpp 0
- In the constructor we initialize our class variables. We need
- to draw the background of our pixmap, as the default is gray.
+ In the constructor we initialize most of our class variables.
Here is the implementation of \c saveImage():
@@ -247,7 +246,15 @@
\snippet widgets/tablet/tabletcanvas.cpp 4
- We simply draw the pixmap to the top left of the widget.
+ The first time Qt calls paintEvent(), m_pixmap is default-constructed, so
+ QPixmap::isNull() returns \c true. Now that we know which screen we will be
+ rendering to, we can create a pixmap with the appropriate resolution.
+ The size of the pixmap with which we fill the window depends on the screen
+ resolution, as the example does not support zoom; and it may be that one
+ screen is \l {High DPI Displays}{high DPI} while another is not. We need to
+ draw the background too, as the default is gray.
+
+ After that, we simply draw the pixmap to the top left of the widget.
Here is the implementation of \c paintPixmap():
diff --git a/examples/widgets/graphicsview/collidingmice/mouse.cpp b/examples/widgets/graphicsview/collidingmice/mouse.cpp
index b94c650c18..cc1a15cd82 100644
--- a/examples/widgets/graphicsview/collidingmice/mouse.cpp
+++ b/examples/widgets/graphicsview/collidingmice/mouse.cpp
@@ -54,7 +54,7 @@
#include <QPainter>
#include <QStyleOption>
-#include <math.h>
+#include <cmath>
static const double Pi = 3.14159265358979323846264338327950288419717;
static double TwoPi = 2.0 * Pi;
@@ -140,9 +140,7 @@ void Mouse::advance(int step)
//! [5]
QLineF lineToCenter(QPointF(0, 0), mapFromScene(0, 0));
if (lineToCenter.length() > 150) {
- qreal angleToCenter = ::acos(lineToCenter.dx() / lineToCenter.length());
- if (lineToCenter.dy() < 0)
- angleToCenter = TwoPi - angleToCenter;
+ qreal angleToCenter = std::atan2(lineToCenter.dy(), lineToCenter.dx());
angleToCenter = normalizeAngle((Pi - angleToCenter) + Pi / 2);
if (angleToCenter < Pi && angleToCenter > Pi / 4) {
@@ -171,9 +169,7 @@ void Mouse::advance(int step)
continue;
QLineF lineToMouse(QPointF(0, 0), mapFromItem(item, 0, 0));
- qreal angleToMouse = ::acos(lineToMouse.dx() / lineToMouse.length());
- if (lineToMouse.dy() < 0)
- angleToMouse = TwoPi - angleToMouse;
+ qreal angleToMouse = std::atan2(lineToMouse.dy(), lineToMouse.dx());
angleToMouse = normalizeAngle((Pi - angleToMouse) + Pi / 2);
if (angleToMouse >= 0 && angleToMouse < Pi / 2) {
diff --git a/examples/widgets/graphicsview/diagramscene/arrow.cpp b/examples/widgets/graphicsview/diagramscene/arrow.cpp
index 012b9ea2ed..ae7fa7af90 100644
--- a/examples/widgets/graphicsview/diagramscene/arrow.cpp
+++ b/examples/widgets/graphicsview/diagramscene/arrow.cpp
@@ -51,7 +51,7 @@
#include "arrow.h"
-#include <math.h>
+#include <cmath>
#include <QPen>
#include <QPainter>
@@ -132,9 +132,7 @@ void Arrow::paint(QPainter *painter, const QStyleOptionGraphicsItem *,
setLine(QLineF(intersectPoint, myStartItem->pos()));
//! [5] //! [6]
- double angle = ::acos(line().dx() / line().length());
- if (line().dy() >= 0)
- angle = (Pi * 2) - angle;
+ double angle = std::atan2(-line().dy(), line().dx());
QPointF arrowP1 = line().p1() + QPointF(sin(angle + Pi / 3) * arrowSize,
cos(angle + Pi / 3) * arrowSize);
diff --git a/examples/widgets/graphicsview/elasticnodes/edge.cpp b/examples/widgets/graphicsview/elasticnodes/edge.cpp
index e794e803cf..d9e4c62e34 100644
--- a/examples/widgets/graphicsview/elasticnodes/edge.cpp
+++ b/examples/widgets/graphicsview/elasticnodes/edge.cpp
@@ -51,12 +51,11 @@
#include "edge.h"
#include "node.h"
-#include <math.h>
+#include <cmath>
#include <QPainter>
static const double Pi = 3.14159265358979323846264338327950288419717;
-static double TwoPi = 2.0 * Pi;
//! [0]
Edge::Edge(Node *sourceNode, Node *destNode)
@@ -139,9 +138,7 @@ void Edge::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
//! [6]
// Draw the arrows
- double angle = ::acos(line.dx() / line.length());
- if (line.dy() >= 0)
- angle = TwoPi - angle;
+ double angle = std::atan2(-line.dy(), line.dx());
QPointF sourceArrowP1 = sourcePoint + QPointF(sin(angle + Pi / 3) * arrowSize,
cos(angle + Pi / 3) * arrowSize);
diff --git a/examples/widgets/itemviews/chart/pieview.cpp b/examples/widgets/itemviews/chart/pieview.cpp
index fb439fae67..942bbe5ca5 100644
--- a/examples/widgets/itemviews/chart/pieview.cpp
+++ b/examples/widgets/itemviews/chart/pieview.cpp
@@ -125,9 +125,9 @@ QModelIndex PieView::indexAt(const QPoint &point) const
return QModelIndex();
// Determine the angle of the point.
- double angle = (180 / M_PI) * std::acos(cx / d);
- if (cy < 0)
- angle = 360 - angle;
+ double angle = (180 / M_PI) * std::atan2(cy, cx);
+ if (angle < 0)
+ angle = 360 + angle;
// Find the relevant slice of the pie.
double startAngle = 0.0;
diff --git a/examples/widgets/mainwindows/mainwindow/mainwindow.cpp b/examples/widgets/mainwindows/mainwindow/mainwindow.cpp
index 10e3dd045a..afceddfca1 100644
--- a/examples/widgets/mainwindows/mainwindow/mainwindow.cpp
+++ b/examples/widgets/mainwindows/mainwindow/mainwindow.cpp
@@ -63,7 +63,6 @@
#include <QFileDialog>
#include <QDialogButtonBox>
#include <QMessageBox>
-#include <QSignalMapper>
#include <QApplication>
#include <QPainter>
#include <QMouseEvent>
diff --git a/examples/widgets/widgets/tablet/tabletcanvas.cpp b/examples/widgets/widgets/tablet/tabletcanvas.cpp
index 03e05e42f6..7cae85e6e6 100644
--- a/examples/widgets/widgets/tablet/tabletcanvas.cpp
+++ b/examples/widgets/widgets/tablet/tabletcanvas.cpp
@@ -65,21 +65,9 @@ TabletCanvas::TabletCanvas()
, m_deviceDown(false)
{
resize(500, 500);
- initPixmap();
setAutoFillBackground(true);
setAttribute(Qt::WA_TabletTracking);
}
-
-void TabletCanvas::initPixmap()
-{
- QPixmap newPixmap = QPixmap(width(), height());
- newPixmap.fill(Qt::white);
- QPainter painter(&newPixmap);
- if (!m_pixmap.isNull())
- painter.drawPixmap(0, 0, m_pixmap);
- painter.end();
- m_pixmap = newPixmap;
-}
//! [0]
//! [1]
@@ -105,23 +93,26 @@ bool TabletCanvas::loadImage(const QString &file)
//! [3]
void TabletCanvas::tabletEvent(QTabletEvent *event)
{
-
switch (event->type()) {
case QEvent::TabletPress:
if (!m_deviceDown) {
m_deviceDown = true;
lastPoint.pos = event->posF();
+ lastPoint.pressure = event->pressure();
lastPoint.rotation = event->rotation();
}
break;
case QEvent::TabletMove:
+#ifndef Q_OS_IOS
if (event->device() == QTabletEvent::RotationStylus)
updateCursor(event);
+#endif
if (m_deviceDown) {
updateBrush(event);
QPainter painter(&m_pixmap);
paintPixmap(painter, event);
lastPoint.pos = event->posF();
+ lastPoint.pressure = event->pressure();
lastPoint.rotation = event->rotation();
}
break;
@@ -138,8 +129,23 @@ void TabletCanvas::tabletEvent(QTabletEvent *event)
//! [3]
//! [4]
+void TabletCanvas::initPixmap()
+{
+ qreal dpr = devicePixelRatioF();
+ QPixmap newPixmap = QPixmap(width() * dpr, height() * dpr);
+ newPixmap.setDevicePixelRatio(dpr);
+ newPixmap.fill(Qt::white);
+ QPainter painter(&newPixmap);
+ if (!m_pixmap.isNull())
+ painter.drawPixmap(0, 0, m_pixmap);
+ painter.end();
+ m_pixmap = newPixmap;
+}
+
void TabletCanvas::paintEvent(QPaintEvent *)
{
+ if (m_pixmap.isNull())
+ initPixmap();
QPainter painter(this);
painter.drawPixmap(0, 0, m_pixmap);
}
@@ -171,13 +177,14 @@ void TabletCanvas::paintPixmap(QPainter &painter, QTabletEvent *event)
painter.setPen(Qt::NoPen);
painter.setBrush(m_brush);
QPolygonF poly;
- qreal halfWidth = m_pen.widthF();
- QPointF brushAdjust(qSin(qDegreesToRadians(lastPoint.rotation)) * halfWidth,
- qCos(qDegreesToRadians(lastPoint.rotation)) * halfWidth);
+ qreal halfWidth = pressureToWidth(lastPoint.pressure);
+ QPointF brushAdjust(qSin(qDegreesToRadians(-lastPoint.rotation)) * halfWidth,
+ qCos(qDegreesToRadians(-lastPoint.rotation)) * halfWidth);
poly << lastPoint.pos + brushAdjust;
poly << lastPoint.pos - brushAdjust;
- brushAdjust = QPointF(qSin(qDegreesToRadians(event->rotation())) * halfWidth,
- qCos(qDegreesToRadians(event->rotation())) * halfWidth);
+ halfWidth = m_pen.widthF();
+ brushAdjust = QPointF(qSin(qDegreesToRadians(-event->rotation())) * halfWidth,
+ qCos(qDegreesToRadians(-event->rotation())) * halfWidth);
poly << event->posF() - brushAdjust;
poly << event->posF() + brushAdjust;
painter.drawConvexPolygon(poly);
@@ -215,6 +222,11 @@ void TabletCanvas::paintPixmap(QPainter &painter, QTabletEvent *event)
}
//! [5]
+qreal TabletCanvas::pressureToWidth(qreal pressure)
+{
+ return pressure * 10 + 1;
+}
+
//! [7]
void TabletCanvas::updateBrush(const QTabletEvent *event)
{
@@ -260,7 +272,7 @@ void TabletCanvas::updateBrush(const QTabletEvent *event)
//! [9] //! [10]
switch (m_lineWidthValuator) {
case PressureValuator:
- m_pen.setWidthF(event->pressure() * 10 + 1);
+ m_pen.setWidthF(pressureToWidth(event->pressure()));
break;
case TiltValuator:
m_pen.setWidthF(maximum(abs(vValue - 127), abs(hValue - 127)) / 12);
@@ -305,7 +317,7 @@ void TabletCanvas::updateCursor(const QTabletEvent *event)
QPainter painter(&img);
QTransform transform = painter.transform();
transform.translate(16, 16);
- transform.rotate(-event->rotation());
+ transform.rotate(event->rotation());
painter.setTransform(transform);
painter.setCompositionMode(QPainter::CompositionMode_DestinationIn);
painter.drawImage(-24, -24, origImg);
diff --git a/examples/widgets/widgets/tablet/tabletcanvas.h b/examples/widgets/widgets/tablet/tabletcanvas.h
index 1784e05916..a1b31c65bf 100644
--- a/examples/widgets/widgets/tablet/tabletcanvas.h
+++ b/examples/widgets/widgets/tablet/tabletcanvas.h
@@ -103,6 +103,7 @@ private:
void initPixmap();
void paintPixmap(QPainter &painter, QTabletEvent *event);
Qt::BrushStyle brushPattern(qreal value);
+ qreal pressureToWidth(qreal pressure);
void updateBrush(const QTabletEvent *event);
void updateCursor(const QTabletEvent *event);
@@ -117,6 +118,7 @@ private:
struct Point {
QPointF pos;
+ qreal pressure;
qreal rotation;
} lastPoint;
};
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 18:17:39 +0000