JKQtPlotter/examples/rgbimageplot_qt/rgbimageplot_qt.cpp
2022-04-22 13:27:31 +02:00

79 lines
2.5 KiB
C++

/** \example rgbimageplot_qt.cpp
* JKQTPlotter: Examples: `QImage` as a Graph
*
* \ref JKQTPlotterImagePlotQImageRGB
*/
#include <QApplication>
#include <cmath>
#include "jkqtplotter/jkqtplotter.h"
#include "jkqtplotter/graphs/jkqtpscatter.h"
#include "jkqtplotter/graphs/jkqtpimagergb.h"
int main(int argc, char* argv[])
{
#if QT_VERSION >= QT_VERSION_CHECK(5,6,0) && QT_VERSION < QT_VERSION_CHECK(6,0,0)
QApplication::setAttribute(Qt::AA_EnableHighDpiScaling); // DPI support
QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps); //HiDPI pixmaps
#endif
QApplication app(argc, argv);
JKQTPlotter plot;
// 1. create a plotter window and get a pointer to the internal datastore (for convenience)
plot.getPlotter()->setUseAntiAliasingForGraphs(true); // nicer (but slower) plotting
plot.getPlotter()->setUseAntiAliasingForSystem(true); // nicer (but slower) plotting
plot.getPlotter()->setUseAntiAliasingForText(true); // nicer (but slower) text rendering
// 2. now we open a BMP-file and load it into an OpenCV cv::Mat
QImage image(":/example.bmp");
// 3. create a graph (JKQTPImage) with a pointer to the QImage-object, generated above
JKQTPImage* graph=new JKQTPImage(&plot);
graph->setTitle("");
// copy the image into the graph (optionally you could also give a pointer to a QImage,
// but then you need to ensure that the QImage is available as long as the JKQTPImage
// instace lives)
graph->setImage(image);
// where does the image start in the plot, given in plot-axis-coordinates (bottom-left corner)
graph->setX(0);
graph->setY(0);
// width/height of the image in plot coordinates
graph->setWidth(image.width());
graph->setHeight(image.height());
// 4. add the graphs to the plot, so it is actually displayed
plot.addGraph(graph);
// 5. set axis labels
plot.getXAxis()->setAxisLabel("x [pixels]");
plot.getYAxis()->setAxisLabel("y [pixels]");
// 5.1 invert y-axis, so image is oriented correctly
plot.getYAxis()->setInverted(true);
// 6. fix axis aspect ratio to width/height, so pixels are square
plot.getPlotter()->setMaintainAspectRatio(true);
plot.getPlotter()->setAspectRatio(double(image.width())/double(image.height()));
// 7. autoscale the plot so the graph is contained
plot.zoomToFit();
// 8. show plotter and make it a decent size
plot.show();
plot.resize(800,600);
plot.setWindowTitle("JKQTPImage");
return app.exec();
}