/** \example jkqtplotter_simpletest_filledgraphs.cpp * Shows how to use filled graphs with JKQTPlotter * * \ref JKQTPlotterFilledGraphs */ #include #include "jkqtplotter/jkqtplotter.h" #include "jkqtplotter/jkqtpgraphsfilledcurve.h" int main(int argc, char* argv[]) { QApplication app(argc, argv); // 1. create a plotter window and get a pointer to the internal datastore (for convenience) JKQTPlotter plot; JKQTPDatastore* ds=plot.getDatastore(); // 2. now we create 4 datacolumns with length 256 entries in the datastore // these will later hold the RGB-histogram and a linear x-values vector // - the x-values are directly initialized as linear vector 0..255 in 256 steps // - the other columns are generated and size_t-type indexes are stored for later // reference to these columns in the graphs- size_t columnX=ds->addLinearColumn(256, 0, 255, "x"); size_t columnR=ds->addColumn(256, "historam_R"); size_t columnG=ds->addColumn(256, "historam_G"); size_t columnB=ds->addColumn(256, "historam_B"); // - now all columns for RGB are initialized to 0 ds->setAll(columnG, 0); ds->setAll(columnR, 0); ds->setAll(columnB, 0); // 3. now we open a BMP-file and load it into a QImage QImage image(":/example.bmp"); // ... and calculate the RGB-histograms for (int y=0; yinc(columnR, qRed(pix), 1); ds->inc(columnG, qGreen(pix), 1); ds->inc(columnB, qBlue(pix), 1); } } // ... and normalize histograms ds->scaleColumnValues(columnR, 100.0/static_cast(image.width()*image.height())); ds->scaleColumnValues(columnG, 100.0/static_cast(image.width()*image.height())); ds->scaleColumnValues(columnB, 100.0/static_cast(image.width()*image.height())); // 4. now we add three semi-transparent, filled curve plots, one for each histogram JKQTPFilledCurveXGraph* graphR=new JKQTPFilledCurveXGraph(&plot); JKQTPFilledCurveXGraph* graphG=new JKQTPFilledCurveXGraph(&plot); JKQTPFilledCurveXGraph* graphB=new JKQTPFilledCurveXGraph(&plot); // set graph titles graphR->setTitle("R-channel"); graphG->setTitle("G-channel"); graphB->setTitle("B-channel"); // set graph colors (lines: non-transparent, fill: semi-transparent) and style QColor col; col=QColor("red"); graphR->setColor(col); col.setAlphaF(0.25); graphR->setFillColor(col); col=QColor("green"); graphG->setColor(col); col.setAlphaF(0.25); graphG->setFillColor(col); col=QColor("blue"); graphB->setColor(col); col.setAlphaF(0.25); graphB->setFillColor(col); graphR->setLineWidth(1); graphG->setLineWidth(1); graphB->setLineWidth(1); // set data graphR->setXColumn(columnX); graphR->setYColumn(columnR); graphG->setXColumn(columnX); graphG->setYColumn(columnG); graphB->setXColumn(columnX); graphB->setYColumn(columnB); // add the graphs to the plot, so they are actually displayed plot.addGraph(graphB); plot.addGraph(graphG); plot.addGraph(graphR); // 5. set axis labels plot.getXAxis()->setAxisLabel("R/G/B-value"); plot.getYAxis()->setAxisLabel("normalized frequency [%]"); // 4. set the maximum size of the plot to 0..100% and 0..256 plot.setAbsoluteX(0,256); plot.setAbsoluteY(0,100); // ... and scale plot automatically plot.zoomToFit(); // 5. show plotter and make it a decent size plot.show(); plot.resize(600,400); return app.exec(); }