You will have to re-organize your annotations and how you map their positions anyway. Or you save your annotations relative to the coordinate system of your image (= QGraphicsPixmapItem), assuming your annotation will always be on the image. Otherwise they could point somewhere else, when your scene does not have the same size and the image item does not have the same position in your scene. You have to save the zoom factor as well to ensure that they are still valid. Saving the annotation is simple, but I'm sure you want to save them, so that you can load the same image and they still point to the same location of the image where they got set initally, right?! Save marker coordinates that way, that I can simply reload those back to the scene, at same position as I have set them before If the button is located at (200, 200) on your screen, it will output (-100, -100). This maps (100,100) on your screen to myPushButton's coordinate system. So you translate it into the coords of the widget from where you call this mapping function.įor example myPushButton->mapFromGlobal(QPoint(100, 100)) You have a point on your screen and want to know what this point might be in Widget X's coordinates. system of the widget where this point actually is. Therefore you need to map it to the coord. Note: It is possible to create a QCursor before. when using static stuff like QToolTip::show(.) you can be sure, that it will most likely use the global/screen coordinate system. To set or get the position of the mouse cursor use the static methods QCursor::pos () and QCursor::setPos (). You click (10, 10) in scene- or in some widget's coords, but global (10, 10) is somewhere else. Otherwise something happens like in your initial version. Every time you have different coordinate systems and you want to 'sync' them (talking about the same point in both systems). Maybe you need/want to fix it said in Confusion with mouse coordinates:īecause now I am confused when to use mapToScene, mapFromGlobal, maptoGlobal, widgetCoordinates and so on. So the first pixel of the image will not have (0,0), therefore the annotation also wont, but they depend on your scroll factor of your scene.

currently they are showing the scene coords.

Then it just depends on what your coordinates really need to show. QGraphicsPixmapItem *anotation = new QGraphicsPixmapItem Īnotation->setFlag(QGraphicsItem::ItemIsMovable) Painter->drawText(QRect(0, 0, 50, 50), Qt::AlignCenter, QString::number(num)) Painter->setFont(QFont('Verdana', 21, QFont::ExtraBold)) QTextStream(&stream) setPen(QColor(0, 0, 0, 255)) void QEnhancedGraphicsView::slotPaintMarker(QPoint pos, int num) currently the annoations appear not on the image where you actually click in your scene. is to use Widget Reflector widget coordinate system UE4 Drag and Drop: Place PaperCharacter Over Image Widget Mouse wheel zooms in until a specific zoom. Played around a little with your example and draged an image in to test the actual annotation function. QToolTip::showText(this->mapToGlobal(event->pos()), text) QToolTip::showText(event->pos(), text) Global coordinate-system, but widget coord. void QEnhancedGraphicsView::mouseMoveEvent(QMouseEvent *event) The mouseEvent is in widget's coordinates, while you show the QToolTip in global coordinates. If you compare the offset of your clicked point with the annotation, you will set that it's about the same difference.Īfter checking your code. The ToolTip shows up far from the mouse position. QCPGraphDataContainer::const_iterator end = ui->myPlot->selectedGraphs().front()->data()->at(dataRange.Said in Confusion with mouse coordinates: QCPGraphDataContainer::const_iterator begin = ui->myPlot->selectedGraphs().front()->data()->at(dataRange.begin()) // get range begin iterator from index QCPDataSelection selection = ui->myPlot->selectedGraphs().front()->selection() įoreach (QCPDataRange dataRange, selection.dataRanges()) if the first click after graph selection was on the graph, the second click will be incorrect

find a data point's value at closest coordinate to mouse clickĭouble xCoord = ui->myPlot->xAxis->pixelToCoord(_mouseEvent->pos().x()) ĭouble 圜oord = ui->myPlot->yAxis->pixelToCoord(_mouseEvent->pos().y()) QMouseEvent *_mouseEvent = static_cast(event) }if(target = ui->myPlot & event->type() = QEvent::MouseButtonPress & Only upon clicking on the new point a second time will it show the correct value.īool MainWindow::eventFilter(QObject *target, QEvent *event) However, if you select a point the second time (while the graph is still selected), it will show the value from the first click after graph selection. Hi all, could somebody elaborate on pu-lnull-mezon's comment?īelow is what I'm currently using, but it is not reliable as: if you select a graph and then click on a point, it will show the correct value.

Mouse coordinates in qt