I want to display the same image at different position. Image should display at all the position. I am using Qpixmap for placing image. Can any one suggest how to do it?.
You can use QLabel for this:
QList<QPoint> points = QList<QPoint>()
<< QPoint(0, 0)
<< QPoint(100, 100)
<< QPoint(200, 200);
QPixmap pixmap;
for (int i = 0; i < points.size(); ++i)
{
QLabel* label = new QLabel;
label->setPixmap(pixmap);
label->setGeometry(QRect(points[i], pixmap.size()));
label->show();
}
Related
My goal is to print a QImage which consists of random RGB values. However, I got this error:
No member named 'graphicsView' in 'Ui::MainWindow'
My code is here:
int sizeX = 300; int sizeY = 300;
QImage img = QImage(sizeX, sizeY, QImage::Format_RGB32);
for(int i=0; i<sizeX; i++){
for(int j=0; j<sizeY; j++){
img.setPixel(i, j, qRgb(rand()%256, rand()%256, rand()%256));
}
}
QGraphicsScene *graphic = new QGraphicsScene(this);
graphic->addPixmap(QPixmap::fromImage(img));
ui->graphicsView->setScene(graphic);
m_ig = new ImageGenerator;
connect(m_ig, &ImageGenerator::sigTest, this, &MainWindow::slotTest);
Thanks. Best regards!
Make sure that Graphics View widget is added to your MainWindow form (usually mainwindow.ui file) in Design section of QtCreator.
Check if its objectName is actually graphicsView.
Try to rebuild your project.
I wrote a program in Qt, which visualizes a processed pointcloud (3D-points) by using Q3DScatter.
Now I want to add calculated keypoints with a different color.
Is that possible?
Does anyboy have some experiences with that?
Below you can see the part of code, where the point cloud is added to the data array.
QScatterDataArray * dataArray = new QScatterDataArray;
dataArray->resize(vector_seg_x->size());
QScatterDataItem * ptrToDataArray = &dataArray->first();
for(int i = 0; i < vector_seg_x->size();i++){
ptrToDataArray->setPosition(QVector3D(
(double)(iter_seg_x[i]),
(double)(iter_seg_y[i]),
(double)(iter_seg_z[i])));
ptrToDataArray++;
}
m_graph_seg->seriesList().at(0)->dataProxy()->resetArray(dataArray);
You can only set a color/gradient for a whole point list:
Q3DScatter scatter;
scatter.setFlags(scatter.flags() ^ Qt::FramelessWindowHint);
scatter.addSeries(new QScatter3DSeries);
scatter.addSeries(new QScatter3DSeries);
{
QScatterDataArray *data = new QScatterDataArray;
*data << QVector3D(0.5f, 0.5f, 0.5f) << QVector3D(-0.3f, -0.5f, -0.4f) << QVector3D(0.0f, -0.3f, 0.2f);
scatter.seriesList().at(0)->dataProxy()->resetArray(data);
QLinearGradient linearGrad(QPointF(100, 100), QPointF(200, 200));
linearGrad.setColorAt(0, Qt::blue);
linearGrad.setColorAt(1, Qt::red);
scatter.seriesList().at(0)->setBaseGradient(linearGrad);
scatter.seriesList().at(0)->setColorStyle(Q3DTheme::ColorStyle::ColorStyleObjectGradient);
}
{
QScatterDataArray *data = new QScatterDataArray;
*data << QVector3D(0.f, 0.f, 0.f);
scatter.seriesList().at(1)->dataProxy()->resetArray(data);
scatter.seriesList().at(1)->setBaseColor(Qt::green);
}
scatter.show();
I have subclassed a qgraphicsscene and trying to get the mouse coords inside a "normal" function. I only get it working on "mouse involved" function. Sorry I'm amateur programmer.
For exmample here scenePos() works:
void mousePressEvent(QGraphicsSceneMouseEvent *event)
{
// qDebug() << "Custom scene clicked.";
if(event->modifiers() == Qt::ControlModifier) {
if(event->button() == Qt::LeftButton) {
QPointF pos = {event->scenePos().x(), 70};
addChordnueve(pos); // crea 1 item at mouse x e y = 70
// } if(event->modifiers() == Qt::ControlModifier & event->modifiers() == Qt::ShiftModifier) {
qDebug() << "Control!!!";}}
Here it doesn't works at all, but got QCursor::pos() giving "weird" positions:
void preaddExtChord()
{
auto *hellos = scenePos(); //<- It doesn't works
int xplace = QCursor::pos().x()-620;
int yplace = QCursor::pos().y()-380;
QGraphicsSimpleTextItem *item = new QGraphicsSimpleTextItem("n");
item->setFont(QFont ("omheads", 20));
item->setPos(xplace, yplace);
addItem(item);
}
I searched a lot during months but couldn't find a solution,...
maybe I'm doing a wrong approach, or either there is some easier possibilitie to get the mouse coords inside this type of functions?
Thanks! :-)
If you want to obtain the position with respect to the cursor scene you must first obtain that QGraphicsView is below the cursor (a QGraphicsScene can be part of QGraphicsView), for this we must iterate and verify if it is inside the viewport, then calculate the position with respect to the scene using the mapToScene method of QGraphicsView:
QPoint p = QCursor::pos();
for(QGraphicsView *view: views()){
QWidget *viewport = view->viewport();
QRect vr = viewport->rect();
QPoint vp = viewport->mapFromGlobal(p);
if(vr.contains(vp)){
QPointF sp = view->mapToScene(vp);
QGraphicsSimpleTextItem *item = new QGraphicsSimpleTextItem("n");
item->setFont(QFont("omheads", 20));
item->setPos(sp);
addItem(item);
}
}
QPainter p(this);
for (int i = 0; i < this->actions().count(); ++i)
{
QAction *action = this->actions().at(i);
QRect actionRect = ...........
QStyleOptionMenuItem opt;
initStyleOption(&opt, action);
opt.rect = actionRect;
QString strPicPath="/h/downloads/tableviewenabledBackGroundImageId.jpg";
QPixmap pic(strPicPath);
pic=pic.scaled(opt.rect.size());
opt.palette.setBrush(QPalette::Background,QBrush(pic));
p.fillRect(opt.rect,opt.palette.background());
style()->drawControl(QStyle::CE_MenuItem, &opt, &p, this);
}
i need get actionRect of QMenu for paint selected menu Item with out Using Qt's Stylesheet.
thanks in advance
Try this->actionGeometry(QAction*), which should return the correct QRect.
I used this in one of my programs, where it worked quite well.
I have QGraphicsScene, which size is 62450x4750. Somethimes I need to make screenshot of whole scene and save it to file. I tried like this:
QPixmap wholeScene(scene.sceneRect().size().toSize());
{
QPainter wholeScenePainter(&wholeScene);
scene.render(&wholeScenePainter);
}
// saving pixmap
or
QPixmap wholeScene(scene.sceneRect().size().toSize());
{
QPainter wholeScenePainter(&wholeScene);
int x = 0;
int portion = 32768; //
while( x < scene.sceneRect().width()) {
int width = scene.sceneRect().width() - x > portion ? portion : scene.sceneRect().width() - x;
QRect rect(x, 0, width, scene.sceneRect().height());
scene.render(&wholeScenePainter, rect, rect);
x += width;
}
}
// saving pixmap
or
QPixmap wholeScene(scene.sceneRect().size().toSize());
{
QPainter wholeScenePainter(&wholeScene);
int x = 0;
int portion = 4096;
while( x < scene.sceneRect().width()) {
int width = scene.sceneRect().width() - x > portion ? portion : scene.sceneRect().width() - x;
QRect rect(x, 0, width, scene.sceneRect().height());
QPixmap temp(rect.size());
QPainter p(&temp);
scene.render(&p, QRect(0, 0, rect.width(), rect.height()), rect);
wholeScenePainter.drawPixmap(x,0, temp);
//temp.save(QString("print%1.png").arg(QString::number(x)), "PNG");
x += width;
}
}
// saving pixmap
But every time I get the Image(Pixmap) cuted by width on 32768 px.
According to the documentation, QPainter does not support coordinates larger than +/- 32768. This does not appear to be fixed in Qt 5 either.
Maybe you can solve this by rendering the scene in multiple passes, e.g. through translation and clipping. You can render the scene in multiple blocks of max 32768x32768 pixels and put them in the proper position in the final image.