qt 简单图片马赛克demo

#include "dialog.h" #include "ui_dialog.h" #include <QPainter> #include <QMouseEvent> #include <QBrush> #include <QtMath> #include <QRgb> Dialog::Dialog(QWidget *parent) : QDialog(parent), ui(new Ui::Dialog) { ui->setupUi(this); m_pixmap = QPixmap(":/res/pic.jpg"); m_image = m_pixmap.toImage(); ui->label->setFixedSize(m_pixmap.size()); } Dialog::~Dialog() { delete ui; } void Dialog::paintEvent(QPaintEvent *e) { QPainter p(this);//p(ui->label); p.drawPixmap(0,0,m_pixmap); ui->label->setPixmap(m_pixmap); } void Dialog::mousePressEvent(QMouseEvent *e) { if(e->button() == Qt::LeftButton) { QPainter p; p.begin(&m_pixmap); QPoint temp_point; if(e->pos().x()%20 > 0) { temp_point.setX(e->pos().x()/20*20 + 10); } else { temp_point.setX(e->pos().x()/20*20 - 10); } if(e->pos().y()%20 > 0) { temp_point.setY(e->pos().y()/20*20 + 10); } else { temp_point.setY(e->pos().y()/20*20 - 10); } QRgb rgb = m_image.pixel(temp_point); QColor color; color.setRgb(rgb); color.setAlpha(180); QPen pen; pen.setColor(color); QRect rect(temp_point.x()-10,temp_point.y()-10,20,20); p.fillRect(rect,color); p.end(); update(); } } void Dialog::mouseMoveEvent(QMouseEvent *e) { //if(e->button() == Qt::LeftButton) { QPainter *p = new QPainter; p->begin(&m_pixmap); QPoint temp_point; if(e->pos().x()%20 > 0) { temp_point.setX(e->pos().x()/20*20 + 10); } else { temp_point.setX(e->pos().x()/20*20 - 10); } if(e->pos().y()%20 > 0) { temp_point.setY(e->pos().y()/20*20 + 10); } else { temp_point.setY(e->pos().y()/20*20 - 10); } QRgb rgb = m_image.pixel(temp_point); QColor color; color.setRgb(rgb); color.setAlpha(180); QPen pen; pen.setColor(color); QRect rect(temp_point.x()-10,temp_point.y()-10,20,20); p->fillRect(rect,color); p->end(); update(); } } void Dialog::on_pushButton_restart_clicked() { m_pixmap = QPixmap(":/res/pic.jpg"); update(); }