NEW add JKQTPParametrizedVectorFieldGraph, which draws color-coded ve…

…ctor fields (color from length, angle, or user-supplied data column) + example

doc/CMakeLists.txt

@@ -246,6 +246,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
         #"multithreaded_complex[multithreaded]/multithreaded_complex/--mdfile=${CMAKE_CURRENT_LIST_DIR}/../examples/multithreaded/README.md --complexlabel"
         graphlabels/graphlabels,graphlabels_hor
         vectorfield
+        paramvectorfield
     )
 
 
@@ -275,6 +276,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
         second_axis/JKQTBasePlotter_addSecondaryYAxis,JKQTBasePlotter_addSecondaryXAxis
         graphlabels/JKQTPGLabelAwayFromXAxis,JKQTPGLabelAwayFromYAxis,JKQTPGLabelTowardsXAxis,JKQTPGLabelTowardsYAxis,JKQTPGLabelAboveData,JKQTPGLabelRightHandSide,JKQTPGLabelBelowData,JKQTPGLabelLeftHandSide,JKQTPGLabelCenteredOnData,JKQTPGLabelCenteredOnDataVertical,JKQTPGLSimpleBox,JKQTPGLSimpleBoxVertical,JKQTPGLSimpleBoxAndLine,JKQTPGLSimpleBoxAndLineVertical,JKQTPGLSimpleBoxAndLineONLYLABELS,JKQTPGLSimpleBoxAndLineONLYLABELSVertical/--iteratefunctorsteps--smallscreenshotplot
         vectorfield/JKQTPVectorFieldGraph,JKQTPVectorFieldGraphAnchorBottom,JKQTPVectorFieldGraphAnchorMid,JKQTPVectorFieldGraphAnchorTip,JKQTPVectorFieldGraphAutoscaleLength,JKQTPVectorFieldGraphLengthFromData,JKQTPVectorFieldGraphIgnoreLength,JKQTPVectorFieldGraphIgnoreLengthAutoscaleLineWidthFromLength,JKQTPVectorFieldGraphAutoscaleLengthAutoscaleLineWidthFromLength/--iteratefunctorsteps
+        paramvectorfield/JKQTPParametrizedVectorFieldGraph,JKQTPParametrizedVectorFieldGraphColorFromMagnitude,JKQTPParametrizedVectorFieldGraphColorFromAngle,JKQTPParametrizedVectorFieldGraphDefaultColor/--iteratefunctorsteps
     )
 
 

doc/dox/examples_and_tutorials.dox

@@ -97,6 +97,9 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 <tr><td> \image html vectorfield_small.png
     <td> \subpage JKQTPlotterVectorFieldExample
     <td> `JKQTPVectorFieldGraph`
+<tr><td> \image html paramvectorfield_small.png
+    <td> \subpage JKQTPParametrizedVectorFieldGraphExample
+    <td> `JKQTPParametrizedVectorFieldGraph`
 </table>
 
 

doc/dox/jkqtplotter_plotelements_classdoc.dox

@@ -297,6 +297,9 @@ This group assembles graphs that represent vector fields (i.e. sets of quadruple
     <tr>
       <td>\image html vectorfield_small.png
       <td> JKQTPVectorFieldGraph
+    <tr>
+      <td>\image html paramvectorfield_small.png
+      <td> JKQTPParametrizedVectorFieldGraph
 </table>
 
 

doc/dox/whatsnew.dox

@@ -128,7 +128,9 @@ Changes, compared to  \ref page_whatsnew_V4_0_0 "v4.0.0" include:
     <li>NEW: allow linear-gradient(), currentcolor, ... in brush definitions of style.ini-file ... and using it is cyberpunk and dark styles</li>
     <li>NEW: style simple_noaxes.ini</li>
     <li>NEW: JKQTPXYGraphLabels which can draw a label next to each datapoint in the given x/y-dataset. The labels can be x-/y- or x&y-coordinates or custom, then defined by a user-supplied functor (+example \ref JKQTPlotterGraphLabelsExample)</li>
-    <li>NEW: Base class JKQTPXYAndVectorGraph for graphs like vector fields, e.g. (x,y,dx,dy) or (x,y,angle,length) and an actual implementation JKQTPVectorFieldGraph (+example \ref JKQTPlotterVectorFieldExample)</li>
+    <li>NEW: Base class JKQTPXYAndVectorGraph for graphs like vector fields, e.g. (x,y,dx,dy) or (x,y,angle,length) </li>
+    <li>NEW: JKQTPVectorFieldGraph for drawing "simple" vector fields/quiver plots (+example \ref JKQTPlotterVectorFieldExample)</li>
+    <li>NEW: JKQTPParametrizedVectorFieldGraph for drawing color-coded vector fields/quiver plots (+example \ref JKQTPParametrizedVectorFieldGraphExample)</li>
   </ul></li>
 
   <li>JKQTMathText:<ul>

examples/CMakeLists.txt

@@ -91,6 +91,7 @@ if (JKQtPlotter_BUILD_LIB_JKQTPLOTTER)
     add_subdirectory(paramscatterplot_image)
     add_subdirectory(paramscatterplot_customsymbol)
     add_subdirectory(parsedfunctionplot)
+    add_subdirectory(paramvectorfield)
     add_subdirectory(rgbimageplot)
     add_subdirectory(rgbimageplot_cimg)
     add_subdirectory(rgbimageplot_opencv)

examples/paramvectorfield/CMakeLists.txt

@@ -0,0 +1,25 @@
+cmake_minimum_required(VERSION 3.23)
+
+set(EXAMPLE_NAME paramvectorfield)
+set(EXENAME jkqtptest_${EXAMPLE_NAME})
+
+message( STATUS "..   Building Example ${EXAMPLE_NAME}" )
+
+
+
+add_executable(${EXENAME} WIN32 ${EXAMPLE_NAME}.cpp)
+target_link_libraries(${EXENAME} JKQTPExampleToolsLib)
+target_include_directories(${EXENAME} PRIVATE ../../lib)
+target_link_libraries(${EXENAME} ${jkqtplotter_namespace}JKQTPlotter${jkqtplotter_LIBNAME_VERSION_PART})
+
+# precomiled headers to speed up compilation
+if (JKQtPlotter_BUILD_WITH_PRECOMPILED_HEADERS)
+  target_precompile_headers(${EXENAME} REUSE_FROM jkqtptest_simpletest)
+endif (JKQtPlotter_BUILD_WITH_PRECOMPILED_HEADERS)
+
+
+# Installation
+install(TARGETS ${EXENAME} RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+#Installation of Qt DLLs on Windows
+jkqtplotter_deployqt(${EXENAME})

examples/paramvectorfield/README.md

@@ -0,0 +1,63 @@
+# Example (JKQTPlotter): Vector Field Plot Example {#JKQTPParametrizedVectorFieldGraphExample}
+This project (see [`paramvectorfield`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/paramvectorfield) demonstrates the use of JKQTPParametrizedVectorFieldGraph to visualize a vector field with additional information encoded in the color of the vectors. 
+
+The source code of the main application is (see [`paramvectorfield.cpp`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/paramvectorfield/paramvectorfield.cpp).
+
+Here is a short summary of the important parts of the code:
+
+```.cpp
+    // 1. setup a plotter window and get a pointer to the internal datastore (for convenience)
+    JKQTPlotter plot;
+    JKQTPDatastore* ds=plot.getDatastore();
+
+
+    // 2. make up some arbitrary data to be used for plotting
+    //    this generates a 2D grid of x/y-coordinates and then calculates dx=cos(y)*sqrt(x/3.0) and dy=sin(x)*sqrt(x/3.0)
+    const auto columnXY=ds->addLinearGridColumns(NX, 0, 6, NY, -3, 3,"x","y");
+    const auto columnDX=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return sin(y)*sqrt(x/3.0); });
+    const auto columnDY=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return cos(x)*sqrt(x/3.0); });
+    // now we also calulate a column that encodes some other information that can be color-coded
+    const auto columnC=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return sqrt(fabs(y)); });
+
+
+    // 3. create JKQTPVectorFieldGraph to display the data:
+    JKQTPParametrizedVectorFieldGraph* graph1=new JKQTPParametrizedVectorFieldGraph(&plot);
+    graph1->setXYColumns(columnXY);
+    graph1->setDxColumn(columnDX);
+    graph1->setDyColumn(columnDY);
+    graph1->setColorColumn(columnC);
+    graph1->setTitle(QObject::tr("$\\vec{f}(x,y)=\\bigl[\\sin(y)\\cdot\\sqrt{x/3}, \\cos(x)\\cdot\\sqrt{x/3}\\bigr]^\\mathrm{T}$"));
+
+    // 4. add the graphs to the plot, so it is actually displayed
+    plot.addGraph(graph1);
+
+```
+
+The result looks like this:
+
+![paramvectorfield](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/paramvectorfield.png)
+
+
+By default, the color of the drawn vector is determined from the color column provided to the graph object.
+But you can also choose to not provide a color column and instead set
+
+```.cpp
+        graph1->setVectorColorMode(JKQTPParametrizedVectorFieldGraph::ColorFromMagnitude);
+```
+
+Now the color encodes the actual length (or magnitude) of the vectors:
+
+![paramvectorfield](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/doc/images/JKQTPParametrizedVectorFieldGraphColorFromMagnitude.png)
+
+
+Alternatively 
+
+```.cpp
+        graph1->setVectorColorMode(JKQTPParametrizedVectorFieldGraph::ColorFromAngle);
+```
+
+will color-encode the rotation angle (in radians, 3 o'clock is 0rad) of the vectors:
+
+![paramvectorfield](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/doc/images/JKQTPParametrizedVectorFieldGraphColorFromAngle.png)
+
+

examples/paramvectorfield/paramvectorfield.cpp

@@ -0,0 +1,86 @@
+/** \example vectorfield.cpp
+ * Display a vector field
+ *
+ * \ref JKQTPlotterVectorFieldExample
+ */
+
+#include "jkqtpexampleapplication.h"
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplotter/graphs/jkqtpvectorfield.h"
+#include "jkqtplotter/graphs/jkqtpscatter.h"
+#include "jkqtpexampleapplication.h"
+
+
+#define NX 9
+#define NY 9
+
+int main(int argc, char* argv[])
+{
+
+    JKQTPAppSettingController highDPIController(argc,argv);
+    JKQTPExampleApplication app(argc, argv);
+
+
+    // 1. setup a plotter window and get a pointer to the internal datastore (for convenience)
+    JKQTPlotter plot;
+    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
+    JKQTPDatastore* ds=plot.getDatastore();
+
+
+
+    // 2. make up some arbitrary data to be used for plotting
+    //    this generates a 2D grid of x/y-coordinates and then calculates dx=cos(y)*sqrt(x/3.0) and dy=sin(x)*sqrt(x/3.0)
+    const auto columnXY=ds->addLinearGridColumns(NX, 0, 6, NY, -3, 3,"x","y");
+    const auto columnDX=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return sin(y)*sqrt(x/3.0); });
+    const auto columnDY=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return cos(x)*sqrt(x/3.0); });
+    // now we also calulate a column that encodes some other information that can be color-coded
+    const auto columnC=ds->addCalculatedColumnFromColumn(columnXY.first, columnXY.second, [](double x,double y) { return sqrt(fabs(y)); });
+
+
+    // 3. create JKQTPVectorFieldGraph to display the data:
+    JKQTPParametrizedVectorFieldGraph* graph1=new JKQTPParametrizedVectorFieldGraph(&plot);
+    graph1->setXYColumns(columnXY);
+    graph1->setDxColumn(columnDX);
+    graph1->setDyColumn(columnDY);
+    graph1->setColorColumn(columnC);
+    graph1->setTitle(QObject::tr("$\\vec{f}(x,y)=\\bigl[\\sin(y)\\cdot\\sqrt{x/3}, \\cos(x)\\cdot\\sqrt{x/3}\\bigr]^\\mathrm{T}$"));
+
+    // 4. add the graphs to the plot, so it is actually displayed
+    plot.addGraph(graph1);
+
+    // 5. scale the plot so the graph is contained
+    plot.getPlotter()->setAxisAspectRatio(1);
+    plot.getPlotter()->setAspectRatio(1);
+    plot.getPlotter()->setMaintainAxisAspectRatio(true);
+    plot.getPlotter()->setMaintainAspectRatio(true);
+    plot.zoomToFit();
+
+
+    // show plotter and make it a decent size
+    plot.setWindowTitle("JKQTPVectorFieldGraph example");
+    plot.show();
+    plot.resize(400/plot.devicePixelRatioF(),430/plot.devicePixelRatioF());
+
+
+
+    app.addExportStepFunctor([&](){
+        graph1->setVectorColorMode(JKQTPParametrizedVectorFieldGraph::ColorFromMagnitude);
+        plot.redrawPlot();
+    });
+
+    app.addExportStepFunctor([&](){
+        graph1->setVectorColorMode(JKQTPParametrizedVectorFieldGraph::ColorFromAngle);
+        plot.redrawPlot();
+    });
+
+    app.addExportStepFunctor([&](){
+        graph1->setVectorColorMode(JKQTPParametrizedVectorFieldGraph::DefaultColor);
+        plot.redrawPlot();
+    });
+
+
+    return app.exec();
+}

examples/vectorfield/README.md

@@ -1,5 +1,5 @@
 # Example (JKQTPlotter): Vector Field Plot Example {#JKQTPlotterVectorFieldExample}
-This project (see [`vectorfield`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/vectorfield) demonstrates the use of JKQTPXYvectorfield to add labels to the datapoints of a graph. 
+This project (see [`vectorfield`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/vectorfield) demonstrates the use of JKQTPVectorFieldGraph to visualize a vector field. 
 
 The source code of the main application is (see [`vectorfield.cpp`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/vectorfield/vectorfield.cpp).
 

examples/vectorfield/vectorfield.cpp

@@ -73,7 +73,7 @@ int main(int argc, char* argv[])
     });
     app.addExportStepFunctor([&](){
         graph1->setAnchorPoint(JKQTPVectorFieldGraph::AnchorMid);
-            plot.redrawPlot();
+        plot.redrawPlot();
     });
 
     app.addExportStepFunctor([&](){

lib/jkqtplotter/graphs/jkqtpbarchartbase.h

@@ -123,9 +123,9 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPBarGraphBase: public JKQTPXYBaselineGraph, pub
         /** \brief class constructor */
         JKQTPBarGraphBase(JKQTPlotter* parent);
 
-        /** \brief plots a key marker inside the specified rectangle \a rect */
+        /** \copydoc JKQTPXYBaselineGraph::drawKeyMarker() */
         virtual void drawKeyMarker(JKQTPEnhancedPainter& painter, const QRectF& rect) override;
-        /** \brief returns the color to be used for the key label */
+        /** \copydoc JKQTPXYBaselineGraph::getKeyLabelColor() */
         virtual QColor getKeyLabelColor() const override;
 
 

lib/jkqtplotter/graphs/jkqtpboxplot.h

@@ -111,7 +111,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPBoxplotVerticalGraph: public JKQTPBoxplotGraph
 
         /** \brief plots the graph to the plotter object specified as parent */
         virtual void draw(JKQTPEnhancedPainter& painter) override;
-        /** \brief plots a key marker inside the specified rectangle \a rect */
+        /** \copydoc JKQTPBoxplotGraphBase::drawKeyMarker() */
         virtual void drawKeyMarker(JKQTPEnhancedPainter& painter, const QRectF& rect) override;
 
         /** \copydoc JKQTPPlotElement::getXMinMax() */

lib/jkqtplotter/graphs/jkqtpscatter.cpp

@@ -270,6 +270,7 @@ JKQTPXYParametrizedScatterGraph::JKQTPXYParametrizedScatterGraph(JKQTBasePlotter
     symbolFillDerivationMode=JKQTPColorDerivationMode::JKQTPFFCMLighterColor;
     if (parent) {
         symbolFillDerivationMode=parent->getCurrentPlotterStyle().graphsStyle.defaultGraphStyle.fillColorDerivationMode;
+        palette=parent->getCurrentPlotterStyle().graphsStyle.defaultPalette;
     }
 
     clearSizeColumnFunctor();