Qt加载图片(复合模式)

╰+哭是因爲堅強的太久メ 2021-09-22 10:14 406阅读 0赞

![SouthEast][]

主要代码

#include "imagecomposer.h"
    #include "ui_imagecomposer.h"
    
    static QString mode[35];
    static const QSize resultSize(200,200);
    
    ImageComposer::~ImageComposer()
    {
        delete ui;
    }
    void ImageComposer::paintEvent(QPaintEvent*)
    {
        QPainter painter(this);
        painter.fillRect(rect(),Qt::white);
    }
    ImageComposer::ImageComposer(QWidget *parent) :
        QWidget(parent),
        ui(new Ui::ImageComposer)
    {
        ui->setupUi(this);
    
        resultImage=QImage(resultSize,QImage::Format_ARGB32_Premultiplied);
        ui->sourceLabel->setGeometry(10,10,200,200);
        ui->destinationLabel->setGeometry(230,10,200,200);
        ui->resultLabel->setGeometry(450,10,200,200);
    
        loadImage(":/images/bf.jpg",&sourceImage,ui->sourceLabel);
        loadImage(":/images/md.jpg",&destinationImage,ui->destinationLabel);
    
        for(int i=0;i<35;i++)
        {
            mode[i]="none";
        }
        mode[QPainter::CompositionMode_SourceOver]="SourceOver";
        mode[QPainter::CompositionMode_DestinationOver]="DestinationOver";
        mode[QPainter::CompositionMode_Clear]="Clear";
        mode[QPainter::CompositionMode_Source]="Source";
        mode[QPainter::CompositionMode_Destination]="Destination";
        mode[QPainter::CompositionMode_SourceIn]="SourceIn";
        mode[QPainter::CompositionMode_DestinationIn]="DestinationIn";
        mode[QPainter::CompositionMode_SourceOut]="SourceOut";
        mode[QPainter::CompositionMode_DestinationOut]="Destination";
        mode[QPainter::CompositionMode_SourceAtop]="SourceAtop";
        mode[QPainter::CompositionMode_DestinationAtop]="DestinationAtop";
        mode[QPainter::CompositionMode_Xor]="Xor";
        mode[QPainter::CompositionMode_Plus]="Plus";
        mode[QPainter::CompositionMode_Multiply]="Multiply";
        mode[QPainter::CompositionMode_Screen]="Screen";
        mode[QPainter::CompositionMode_Overlay]="Overlay";
        mode[QPainter::CompositionMode_Darken]="Darken";
        mode[QPainter::CompositionMode_Lighten]="Lighten";
        mode[QPainter::CompositionMode_ColorBurn]="ColorBurn";
        mode[QPainter::CompositionMode_HardLight]="HardLight";
        mode[QPainter::CompositionMode_SoftLight]="SoftLight";
        mode[QPainter::CompositionMode_Difference]="Difference";
        mode[QPainter::CompositionMode_Exclusion]="Exclusion";
    
        ui->groupBox->setGeometry(10,230,640,160);
    
        QGridLayout *layout=new QGridLayout;
        int count,x,y;
        count=x=y=0;
        for(int i=0;i<35;i++)
        {
            if(mode[i]!="none")
            {
                x=count%6;  //列数
                y=count/6;  //行数
                QRadioButton *radioButton=new QRadioButton(mode[i],this);
                layout->addWidget(radioButton,y,x);
    
                connect(radioButton,SIGNAL(clicked()),this,
                        SLOT(onModeRadioButtonClicked()));  //共用一个槽函数
                count++;
            }
        }
        ui->groupBox->setLayout(layout);
    
        resize(660,400);
    }
    void ImageComposer::onModeRadioButtonClicked()
    {
        QObject *object=QObject::sender();
        QRadioButton *sender = qobject_cast<QRadioButton*>(object);//得到单选按钮上的文字
        QPainter::CompositionMode currentMode=
                (QPainter::CompositionMode)findMode(sender->text());
    
        QPainter painter(&resultImage); //清理画布上的垃圾
        painter.setCompositionMode(QPainter::CompositionMode_Source);
        painter.fillRect(resultImage.rect(),Qt::transparent);
    
        painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
        painter.drawImage(0,0,destinationImage);
        painter.setCompositionMode(currentMode);
        painter.drawImage(0,0,sourceImage);
        painter.end();
    
        ui->resultLabel->setPixmap(QPixmap::fromImage(resultImage));
    
       // QMessageBox::information(this,"Test",sender->text());
    }
    int ImageComposer::findMode(const QString &modeString) const
    {
        for(int i=0;i<35;i++)
        {
            if(mode[i] == modeString)
                return i;
        }
        return -1;
    }
    void ImageComposer::loadImage(const QString fileName,QImage *image,QLabel *label)
    {
        image->load(fileName);
        *image=image->scaled(resultSize,Qt::KeepAspectRatio);   //等比例缩放
    
        QImage fixImage(resultSize,QImage::Format_ARGB32_Premultiplied);
        QPainter painter(&fixImage);
    
        painter.setCompositionMode(QPainter::CompositionMode_Source);   //设置复合模式
        painter.fillRect(fixImage.rect(),Qt::transparent);
    
        painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
        painter.drawImage(0,0,*image);
        painter.end();
    
        *image=fixImage;
        label->setPixmap(QPixmap::fromImage(*image));
    
    }
    QPoint ImageComposer::imagePos(const QImage &image) const
    {
        return QPoint((resultSize.width()-image.width())/2,
                      (resultSize.height()-image.height())/2);
    }

源代码链接： [点击打开链接][Link 1]

[SouthEast]: /images/20210920/fcee2038c4be4ddb8c43e802c377744e.png
[Link 1]: http://download.csdn.net/download/zhangxiaoyu_sy/10204471