whellvalue/tpvs17/lpdesigner/lpImgViewer.cpp

#include "lpImgViewer.h"
#include <QResizeEvent>
#include <QWheelEvent>
#include <QRectF>
#include <iostream>
#include <QtDebug>

lpImgViewer::lpImgViewer(QWidget* parent /*= 0*/)
	: QGraphicsView(parent), mpImgItem(NULL), mpInfoLabel(NULL), mpImg(NULL)
{
	lpScene = new QGraphicsScene(parent);
	setScene(lpScene);
    setResizeAnchor(QGraphicsView::AnchorUnderMouse);
	setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
}

lpImgViewer::lpImgViewer(QGraphicsScene *scene, QWidget *parent /*= 0*/)
	: QGraphicsView(scene, parent), mpImgItem(NULL), mpInfoLabel(NULL), mpImg(NULL)
{
    setResizeAnchor(QGraphicsView::AnchorUnderMouse);
	setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
}

QGraphicsPixmapItem* lpImgViewer::setImg(QImage& img)
{
	if (mpImg)
		delete mpImg;
	mpImg = new QImage(img);

	if (!mpImgItem)
		mpImgItem = scene()->addPixmap(QPixmap::fromImage(img));
	else
		mpImgItem->setPixmap(QPixmap::fromImage(img));

	mpImgItem->setOffset(-img.width() / 2.0, -img.height() / 2.0);
	mpImgItem->setPos(0, 0);
	
	mImgOriSize = img.size();
	qreal scale = std::min((qreal)size().width() / img.width(), (qreal)size().height() / img.height());
	scaleImg2(scale);
	mpImgItem->setFlags(QGraphicsItem::ItemIsMovable | QGraphicsItem::ItemIsSelectable);

	this->centerOn(0, 0);
		
	return mpImgItem;
}

void lpImgViewer::wheelEvent(QWheelEvent *evt)
{
    if (mpImgItem)
    {
        qreal numDegrees = evt->angleDelta().y() / 120;

        qreal newScale = transform().m11();
        if (numDegrees > 0)
            newScale *= std::pow(1.1, numDegrees);
        else if (numDegrees < 0)
            newScale *= std::pow(0.9, -numDegrees);

        qreal minScale = std::min((qreal)size().width() / mImgOriSize.width(), (qreal)size().height() / mImgOriSize.height());
        mpImgItem->setTransformOriginPoint(0, 0);
        scaleImg2(newScale);
    }
}

void lpImgViewer::mouseMoveEvent(QMouseEvent *evt)
{
	if (mpImgItem)
	{
		QPoint curpos = (mpImgItem->mapFromScene(this->mapToScene(evt->pos())) +
			QPointF(mImgOriSize.width() / 2.0, mImgOriSize.height() / 2.0) + QPointF(-0.5, -0.5)).toPoint();

		if (mpInfoLabel)
			selectPixel(curpos);
		else
			emit pixelSelected(curpos);
	}

	if (mpImgItem && mpImgItem->isSelected())
	{
		QPointF pos = mpImgItem->scenePos();
		qDebug() << pos;
		emit imgMoved(pos);
	}

    QGraphicsView::mouseMoveEvent(evt);
}

void lpImgViewer::resizeEvent(QResizeEvent* evt)
{
    QGraphicsView::resizeEvent(evt);
}

void lpImgViewer::mouseReleaseEvent(QMouseEvent *evt)
{
	QGraphicsView::mouseReleaseEvent(evt);
	if (mpImgItem)
		mpImgItem->setSelected(false);
}

void lpImgViewer::closeEvent(QCloseEvent *evt)
{
    deleteLater();
}

void lpImgViewer::moveImg(QPointF pos)
{
	if (mpImgItem)
		mpImgItem->setPos(pos);
}

void lpImgViewer::selectPixel(QPoint pos)
{
	if (pos.x() < 0 || pos.y() < 0 || pos.x() > mImgOriSize.width() || pos.y() > mImgOriSize.height())
	{
		mpInfoLabel->setText(QString("out of image..."));
		return;
	}
	if (!mpImg) {
		mpInfoLabel->setText(QString("mpImg is null"));
	}
	QRgb pixel = mpImg->pixel(pos);
	QColor rgb(pixel);
	QColor hsv = rgb.toHsv();
	QString infoStr("Position:[%1, %2]  Color(RGB):[%3, %4, %5] (HSV):[%6, %7, %8]");
	infoStr = infoStr.arg(pos.x()).arg(pos.y())
		.arg(rgb.red()).arg(rgb.green()).arg(rgb.blue())
		.arg(hsv.hue()/2).arg(hsv.saturation()).arg(hsv.value());
	mpInfoLabel->setText(infoStr);
}

void lpImgViewer::scaleImg(QTransform tf, QPointF center)
{
	this->resetTransform();
	this->setTransform(tf);
	this->centerOn(center);
}

void lpImgViewer::scaleImg2(qreal scale)
{
	QTransform t;
	t.scale(scale, scale);
	this->setTransform(t);

	QPointF center = this->mapToScene(width()/2, height()/2);

	emit imgScaled(this->transform(), center);
}

void lpImgViewer::clear()
{
	scene()->clear();
	mpImgItem = NULL;

	if (mpImg)
	{
		delete mpImg;
		mpImg = NULL;
	}
}