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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "mouse.h"
#include <QGraphicsScene>
#include <QPainter>
#include <QRandomGenerator>
#include <QStyleOption>
#include <QtMath>
constexpr qreal Pi = M_PI;
constexpr qreal TwoPi = 2 * M_PI;
static qreal normalizeAngle(qreal angle)
{
while (angle < 0)
angle += TwoPi;
while (angle > TwoPi)
angle -= TwoPi;
return angle;
}
//! [0]
Mouse::Mouse() : color(QRandomGenerator::global()->bounded(256),
QRandomGenerator::global()->bounded(256),
QRandomGenerator::global()->bounded(256))
{
setRotation(QRandomGenerator::global()->bounded(360 * 16));
}
//! [0]
//! [1]
QRectF Mouse::boundingRect() const
{
qreal adjust = 0.5;
return QRectF(-18 - adjust, -22 - adjust,
36 + adjust, 60 + adjust);
}
//! [1]
//! [2]
QPainterPath Mouse::shape() const
{
QPainterPath path;
path.addRect(-10, -20, 20, 40);
return path;
}
//! [2]
//! [3]
void Mouse::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
{
// Body
painter->setBrush(color);
painter->drawEllipse(-10, -20, 20, 40);
// Eyes
painter->setBrush(Qt::white);
painter->drawEllipse(-10, -17, 8, 8);
painter->drawEllipse(2, -17, 8, 8);
// Nose
painter->setBrush(Qt::black);
painter->drawEllipse(QRectF(-2, -22, 4, 4));
// Pupils
painter->drawEllipse(QRectF(-8.0 + mouseEyeDirection, -17, 4, 4));
painter->drawEllipse(QRectF(4.0 + mouseEyeDirection, -17, 4, 4));
// Ears
painter->setBrush(scene()->collidingItems(this).isEmpty() ? Qt::darkYellow : Qt::red);
painter->drawEllipse(-17, -12, 16, 16);
painter->drawEllipse(1, -12, 16, 16);
// Tail
QPainterPath path(QPointF(0, 20));
path.cubicTo(-5, 22, -5, 22, 0, 25);
path.cubicTo(5, 27, 5, 32, 0, 30);
path.cubicTo(-5, 32, -5, 42, 0, 35);
painter->setBrush(Qt::NoBrush);
painter->drawPath(path);
}
//! [3]
//! [4]
void Mouse::advance(int step)
{
if (!step)
return;
//! [4]
// Don't move too far away
//! [5]
QLineF lineToCenter(QPointF(0, 0), mapFromScene(0, 0));
if (lineToCenter.length() > 150) {
qreal angleToCenter = std::atan2(lineToCenter.dy(), lineToCenter.dx());
angleToCenter = normalizeAngle((Pi - angleToCenter) + Pi / 2);
if (angleToCenter < Pi && angleToCenter > Pi / 4) {
// Rotate left
angle += (angle < -Pi / 2) ? 0.25 : -0.25;
} else if (angleToCenter >= Pi && angleToCenter < (Pi + Pi / 2 + Pi / 4)) {
// Rotate right
angle += (angle < Pi / 2) ? 0.25 : -0.25;
}
} else if (::sin(angle) < 0) {
angle += 0.25;
} else if (::sin(angle) > 0) {
angle -= 0.25;
//! [5] //! [6]
}
//! [6]
// Try not to crash with any other mice
//! [7]
const QList<QGraphicsItem *> dangerMice = scene()->items(QPolygonF()
<< mapToScene(0, 0)
<< mapToScene(-30, -50)
<< mapToScene(30, -50));
for (const QGraphicsItem *item : dangerMice) {
if (item == this)
continue;
QLineF lineToMouse(QPointF(0, 0), mapFromItem(item, 0, 0));
qreal angleToMouse = std::atan2(lineToMouse.dy(), lineToMouse.dx());
angleToMouse = normalizeAngle((Pi - angleToMouse) + Pi / 2);
if (angleToMouse >= 0 && angleToMouse < Pi / 2) {
// Rotate right
angle += 0.5;
} else if (angleToMouse <= TwoPi && angleToMouse > (TwoPi - Pi / 2)) {
// Rotate left
angle -= 0.5;
//! [7] //! [8]
}
//! [8] //! [9]
}
//! [9]
// Add some random movement
//! [10]
if (dangerMice.size() > 1 && QRandomGenerator::global()->bounded(10) == 0) {
if (QRandomGenerator::global()->bounded(1))
angle += QRandomGenerator::global()->bounded(1 / 500.0);
else
angle -= QRandomGenerator::global()->bounded(1 / 500.0);
}
//! [10]
//! [11]
speed += (-50 + QRandomGenerator::global()->bounded(100)) / 100.0;
qreal dx = ::sin(angle) * 10;
mouseEyeDirection = (qAbs(dx / 5) < 1) ? 0 : dx / 5;
setRotation(rotation() + dx);
setPos(mapToParent(0, -(3 + sin(speed) * 3)));
}
//! [11]
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