JKQtPlotter/examples/simpletest_rgbimageplot_qt/README.md
jkriege2 0e2237e92f - more refactorings to modernize C++
- fixed JKQTPColumnMathImage with modifiers
- improved documentation
- make use of link_prl/create_prl in QMake projects (see http://doc.qt.io/qt-5/qmake-advanced-usage.html)
2019-01-26 18:00:42 +01:00

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# Example (JKQTPlotter): QImage as a Graph {#JKQTPlotterImagePlotQImageRGB}
This project (see `./examples/simpletest_rgbimageplot_qt/`) simply creates a JKQTPlotter widget (as a new window) and adds an image plot with an image taken from a [QImage](http://doc.qt.io/qt-5/qimage.html) object.
The source code of the main application is (see [`jkqtplotter_simpletest_rgbimageplot_qt.cpp`](../simpletest_rgbimageplot_qt/jkqtplotter_simpletest_rgbimageplot_qt.cpp). the main parts are:
```.cpp
// 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);
```
The result looks like this:
![jkqtplotter_simpletest_imageplot](../../screenshots/jkqtplotter_simpletest_rgbimageplot_qt.png)