added possibility to register custom symbols for JKQTPPlotSymbol()

doc/dox/whatsnew.dox

@@ -44,6 +44,7 @@ Changes, compared to  \ref page_whatsnew_V4_0_0 "v4.0.0" include:
     <li>NEW: made it's delay a global static variable that can be set and red with JKQTPlotter::setGlobalResizeDelay() and JKQTPlotter::getGlobalResizeDelay()</li>
     <li>NEW: Using JKQTMathText::useGuiFonts() for FONT rendering by default</li>
     <li>NEW: added the option to draw a character from a font as symbol (<code>JKQTPCharacterSymbol+QChar('C').unicode()</code> and <code>JKQTPFilledCharacterSymbol+QChar('C').unicode()</code>)</li>
+    <li>NEW: added the option to register a custom symbol using JKQTPRegisterCustomGraphSymbol() </li>
   </ul></li>
   
   <li>JKQTMathText:<ul>

lib/jkqtcommon/jkqtpdrawingtools.cpp

@@ -93,6 +93,7 @@ QString JKQTPGraphSymbols2String(JKQTPGraphSymbols pos) {
         case JKQTPSymbolCount: JKQTPGraphSymbols2String(JKQTPMaxSymbolID);
         case JKQTPCharacterSymbol:
         case JKQTPFilledCharacterSymbol:
+        case JKQTPFirstCustomSymbol:
             break;
     }
     if (pos>=JKQTPCharacterSymbol && pos<=JKQTPCharacterSymbol+0xFFFF) {
@@ -105,6 +106,10 @@ QString JKQTPGraphSymbols2String(JKQTPGraphSymbols pos) {
         while (s.size()<4) s="0"+s;
         return "symbol_filled_char"+s;
     }
+    if (pos>=JKQTPFirstCustomSymbol) {
+        QString s=QString::number(pos-JKQTPFirstCustomSymbol);
+        return "symbol_custom"+s;
+    }
     return "";
 }
 
@@ -177,6 +182,7 @@ QString JKQTPGraphSymbols2NameString(JKQTPGraphSymbols pos) {
         case JKQTPSymbolCount: JKQTPGraphSymbols2NameString(JKQTPMaxSymbolID);
         case JKQTPCharacterSymbol:
         case JKQTPFilledCharacterSymbol:
+        case JKQTPFirstCustomSymbol:
             break;
     }
     if (pos>=JKQTPCharacterSymbol && pos<=JKQTPCharacterSymbol+0xFFFF) {
@@ -185,6 +191,9 @@ QString JKQTPGraphSymbols2NameString(JKQTPGraphSymbols pos) {
     if (pos>=JKQTPFilledCharacterSymbol && pos<=JKQTPFilledCharacterSymbol+0xFFFF) {
         return QObject::tr("filled character")+" '"+QChar(static_cast<uint16_t>(pos-JKQTPFilledCharacterSymbol))+"'";
     }
+    if (pos>=JKQTPFirstCustomSymbol) {
+        return QObject::tr("custom symbol %1").arg(static_cast<uint64_t>(pos-JKQTPFirstCustomSymbol));
+    }
     return "";
 }
 JKQTPGraphSymbols String2JKQTPGraphSymbols(const QString& pos)  {
@@ -279,6 +288,9 @@ JKQTPGraphSymbols String2JKQTPGraphSymbols(const QString& pos)  {
     if (posT.startsWith("symbol_filled_char")) {
         return JKQTPFilledCharacterSymbol+posT.mid(18).toUInt(nullptr,16);
     }
+    if (posT.startsWith("symbol_custom")) {
+        return JKQTPFirstCustomSymbol+posT.mid(13).toUInt();
+    }
     return JKQTPNoSymbol;
 }
 
@@ -538,3 +550,18 @@ QList<QPolygonF> JKQTPSimplifyPolyLines(const QList<QPolygonF> &lines_in, double
     }
     return l;
 }
+
+
+QVector<JKQTPCustomGraphSymbolFunctor> JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore=QVector<JKQTPCustomGraphSymbolFunctor>();
+
+JKQTPGraphSymbols JKQTPRegisterCustomGraphSymbol(JKQTPCustomGraphSymbolFunctor&& f)
+{
+    JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore.emplace_back(std::move(f));
+    return JKQTPFirstCustomSymbol+(JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore.size()-1);
+}
+
+JKQTPGraphSymbols JKQTPRegisterCustomGraphSymbol(const JKQTPCustomGraphSymbolFunctor& f)
+{
+    JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore.emplace_back(f);
+    return JKQTPFirstCustomSymbol+(JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore.size()-1);
+}

lib/jkqtcommon/jkqtpdrawingtools.h

@@ -38,6 +38,7 @@
 #include <cmath>
 #include <utility>
 #include <QDebug>
+#include <QVector>
 #include <QGuiApplication>
 #include "jkqtcommon/jkqtpmathtools.h"
 #include "jkqtcommon/jkqtpcodestructuring.h"
@@ -46,6 +47,31 @@ class JKQTPEnhancedPainter; // forward
 
 
 
+/** \brief functor used to draw a custom JKQTPGraphSymbols
+ * \ingroup jkqtptools_drawing
+ *
+ * Draw the symbol with these properties:
+ *   - center at (0,0)
+ *   - width 1, i.e. x=-0.5...0.5
+ *   - height 1, i.e. y=-0.5...0.5
+ *   - you can assume that a proper pen and brush is set with the correct properties
+ *   - scaling to the final size is donw by JKQTPPlotSymbol()
+ *   - drawing is protected by surronding \c p.save(); and \c p.restore(); in JKQTPPlotSymbol()
+ * .
+ *
+ * As an example, the following code-snippet:
+ * \code
+ *   [](QPainter& p) {
+ *     p.drawEllipse(QPointF(-0.2, -0.2), 0.3, 0.3);
+ *     p.setBrush(Qt::NoBrush);
+ *     p.drawEllipse(QPointF(0.2, -0.2), 0.3, 0.3);
+ *     p.drawEllipse(QPointF(0, 0.2), 0.3, 0.3);
+ *   };
+ * \endcode
+ * generates this symbol: \image html symbols/symbol_custom.png
+ */
+typedef std::function<void(QPainter& p)> JKQTPCustomGraphSymbolFunctor;
+
 /*! \brief tool class with static values used by JKQTPlotter/JKQTBasePlotter
    \ingroup jkqtptools_drawing
    */
@@ -53,6 +79,11 @@ struct JKQTPlotterDrawingTools {
     /** \brief smallest linewidth any line in JKQTPlotter/JKQTBasePlotter may have
      */
     static JKQTCOMMON_LIB_EXPORT const double ABS_MIN_LINEWIDTH;
+    /** \brief stores all custom JKQTPGraphSymbols registered using JKQTPRegisterCustomGraphSymbol
+     * \ingroup jkqtptools_drawing
+     * \internal
+     */
+    static JKQTCOMMON_LIB_EXPORT QVector<JKQTPCustomGraphSymbolFunctor> JKQTPCustomGraphSymbolStore;
 };
 
 
@@ -145,6 +176,8 @@ enum JKQTPGraphSymbols: uint64_t {
                                                                             \image html symbols/symbol_filled_char_at.png "generated by JKQTPFilledCharacterSymbol+QChar('@').unicode()"
                                                                             \image html symbols/symbol_filled_char_club.png "generated by JKQTPFilledCharacterSymbol+QChar(0x2663).unicode()"
                                                                            */
+    JKQTPFirstCustomSymbol=JKQTPFilledCharacterSymbol+0xFFFF+0xF, /*!< \brief draw a completely custom symbol, defined by supplying a functor to JKQTPRegisterCustomGraphSymbol()
+                                                                              \image html symbols/symbol_custom.png "generated by <code>[](QPainter& p) { p.drawEllipse(QPointF(-0.2, -0.2), 0.3, 0.3); p.setBrush(Qt::NoBrush); p.drawEllipse(QPointF(0.2, -0.2), 0.3, 0.3); p.drawEllipse(QPointF(0, 0.2), 0.3, 0.3); };</code>"  */
 };
 
 inline JKQTPGraphSymbols operator+(JKQTPGraphSymbols a, uint8_t b) {
@@ -179,6 +212,25 @@ inline JKQTPGraphSymbols operator+(JKQTPGraphSymbols a, int64_t b) {
     return static_cast<JKQTPGraphSymbols>(static_cast<uint64_t>(a)+b);
 }
 
+/** \brief register a JKQTPCustomGraphSymbolFunctor that draws a custom symbol.Returns an ID that allows to access the symbol!
+ * \ingroup jkqtptools_drawing
+ *
+ * The functor is stored in the global/static store JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore, i.e. these are available throughout the runtime of the program
+ *
+ * \see JKQTPCustomGraphSymbolFunctor for an example
+ */
+JKQTCOMMON_LIB_EXPORT JKQTPGraphSymbols JKQTPRegisterCustomGraphSymbol(JKQTPCustomGraphSymbolFunctor&&);
+
+/** \brief register a JKQTPCustomGraphSymbolFunctor that draws a custom symbol.Returns an ID that allows to access the symbol!
+ * \ingroup jkqtptools_drawing
+ *
+ * The functor is stored in the global/static store JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore, i.e. these are available throughout the runtime of the program
+ *
+ * \see JKQTPCustomGraphSymbolFunctor for an example
+ */
+JKQTCOMMON_LIB_EXPORT JKQTPGraphSymbols JKQTPRegisterCustomGraphSymbol(const JKQTPCustomGraphSymbolFunctor&);
+
+
 /** \brief converts a JKQTPGraphSymbols variable into a identifier string
  * \ingroup jkqtptools_drawing
  */
@@ -193,6 +245,40 @@ JKQTCOMMON_LIB_EXPORT QString JKQTPGraphSymbols2NameString(JKQTPGraphSymbols pos
  */
 JKQTCOMMON_LIB_EXPORT JKQTPGraphSymbols String2JKQTPGraphSymbols(const QString& pos);
 
+/*! \brief plot the specified symbol at pixel position x,y
+   \ingroup jkqtptools_drawing
+
+    \tparam TPainter Type of \a painter: A class like JKQTPEnhancedPainter or <a href="http://doc.qt.io/qt-5/qpainter.html">QPainter</a>
+    \param painter the <a href="http://doc.qt.io/qt-5/qpainter.html">QPainter</a> to draw to
+    \param x x-coordinate of the symbol center
+    \param y y-coordinate of the symbol center
+    \param symbol type of the symbol to plot, see JKQTPGraphSymbols
+    \param size size (width/height) of the symbol around (\a x , \a y)
+    \param symbolLineWidth width of the lines used to draw the symbol
+    \param color color of the symbol lines
+    \param fillColor color of the symbol filling
+    \param symbolFont font used to draw symbols like \c JKQTPCharacterSymbol+QChar('@').unicode()
+
+ */
+template <class TPainter>
+inline void JKQTPPlotSymbol(TPainter& painter, double x, double y, JKQTPGraphSymbols symbol, double size, double symbolLineWidth, QColor color, QColor fillColor, QFont symbolFont);
+
+/*! \brief plot the specified symbol at pixel position x,y
+   \ingroup jkqtptools_drawing
+
+    \param paintDevice the paint device to draw on
+    \param x x-coordinate of the symbol center
+    \param y y-coordinate of the symbol center
+    \param symbol type of the symbol to plot, see JKQTPGraphSymbols
+    \param size size (width/height) of the symbol around (\a x , \a y)
+    \param symbolLineWidth width of the lines used to draw the symbol
+    \param color color of the symbol lines
+    \param fillColor color of the symbol filling
+    \param symbolFont font used to draw symbols like \c JKQTPCharacterSymbol+QChar('@').unicode()
+
+ */
+JKQTCOMMON_LIB_EXPORT void JKQTPPlotSymbol(QPaintDevice& paintDevice, double x, double y, JKQTPGraphSymbols symbol, double size, double symbolLineWidth, QColor color, QColor fillColor, const QFont &symbolFont);
+
 
 
 
@@ -286,40 +372,6 @@ inline void JKQTPPlotDecoratedLine(TPainter& painter, const QLineF& l, JKQTPLine
 /** \brief calculates the tail decorator size from the line width \a line_width, using decoratorSizeFactor and a non-linear scaling function that levels off towards small \a line_width and increases sub-linearly for large ones, so the arrow heads to not grow too much */
 JKQTCOMMON_LIB_EXPORT double JKQTPLineDecoratorStyleCalcDecoratorSize(double line_width, double decoratorSizeFactor);
 
-/*! \brief plot the specified symbol at pixel position x,y
-   \ingroup jkqtptools_drawing
-
-    \tparam TPainter Type of \a painter: A class like JKQTPEnhancedPainter or <a href="http://doc.qt.io/qt-5/qpainter.html">QPainter</a>
-    \param painter the <a href="http://doc.qt.io/qt-5/qpainter.html">QPainter</a> to draw to
-    \param x x-coordinate of the symbol center
-    \param y y-coordinate of the symbol center
-    \param symbol type of the symbol to plot, see JKQTPGraphSymbols
-    \param size size (width/height) of the symbol around (\a x , \a y)
-    \param symbolLineWidth width of the lines used to draw the symbol
-    \param color color of the symbol lines
-    \param fillColor color of the symbol filling
-    \param symbolFont font used to draw symbols like \c JKQTPCharacterSymbol+QChar('@').unicode()
-
- */
-template <class TPainter>
-inline void JKQTPPlotSymbol(TPainter& painter, double x, double y, JKQTPGraphSymbols symbol, double size, double symbolLineWidth, QColor color, QColor fillColor, QFont symbolFont);
-
-/*! \brief plot the specified symbol at pixel position x,y
-   \ingroup jkqtptools_drawing
-
-    \param paintDevice the paint device to draw on
-    \param x x-coordinate of the symbol center
-    \param y y-coordinate of the symbol center
-    \param symbol type of the symbol to plot, see JKQTPGraphSymbols
-    \param size size (width/height) of the symbol around (\a x , \a y)
-    \param symbolLineWidth width of the lines used to draw the symbol
-    \param color color of the symbol lines
-    \param fillColor color of the symbol filling
-    \param symbolFont font used to draw symbols like \c JKQTPCharacterSymbol+QChar('@').unicode()
-
- */
-JKQTCOMMON_LIB_EXPORT void JKQTPPlotSymbol(QPaintDevice& paintDevice, double x, double y, JKQTPGraphSymbols symbol, double size, double symbolLineWidth, QColor color, QColor fillColor, const QFont &symbolFont);
-
 
 
 
@@ -873,6 +925,7 @@ inline void JKQTPPlotSymbol(TPainter& painter, double x, double y, JKQTPGraphSym
         case JKQTPSymbolCount:
         case JKQTPCharacterSymbol:
         case JKQTPFilledCharacterSymbol:
+        case JKQTPFirstCustomSymbol:
             break;
     }
     if (symbol>=JKQTPCharacterSymbol && symbol<=JKQTPCharacterSymbol+0xFFFF) {
@@ -913,6 +966,17 @@ inline void JKQTPPlotSymbol(TPainter& painter, double x, double y, JKQTPGraphSym
         path.addText(0,0,symbolFont, ch),
         painter.drawPath(path);
     }
+    if (symbol>=JKQTPFirstCustomSymbol) {
+        const int idx(static_cast<int>(symbol-JKQTPFirstCustomSymbol));
+        if (idx>=0 && idx<JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore.size()) {
+            painter.setPen(p);
+            painter.translate(QPointF(x,y));
+            painter.scale(symbolSize,symbolSize);
+            painter.setBrush(b);
+            painter.setPen(pDescaled);
+            JKQTPlotterDrawingTools::JKQTPCustomGraphSymbolStore[idx].operator()(painter);
+        }
+    }
 }
 
 template <class TPainter>

tools/jkqtplotter_doc_imagegenerator/jkqtplotter_doc_imagegenerator.cpp

@@ -105,6 +105,18 @@ int main(int argc, char* argv[])
         p.setPen(QPen(QColor("green"),0.5));
         //p.drawRect(2,2,iconsize-4,iconsize-4);
         stopPaintingAndSave(img, p, outputDir.absoluteFilePath("symbol_filled_char_club.png"));
+
+        JKQTPCustomGraphSymbolFunctor f=[](QPainter& p) {
+            p.drawEllipse(QPointF(-0.2, -0.2), 0.3, 0.3);
+            p.setBrush(Qt::NoBrush);
+            p.drawEllipse(QPointF(0.2, -0.2), 0.3, 0.3);
+            p.drawEllipse(QPointF(0, 0.2), 0.3, 0.3);
+        };
+        JKQTPGraphSymbols customs=JKQTPRegisterCustomGraphSymbol(f);
+        startPainting(img, p, iconsize, backgroundColor);
+        JKQTPPlotSymbol(p, iconsize/2,iconsize/2,customs,iconsize-4,2,QColor("blue"), QColor("salmon").lighter(120),QGuiApplication::font().family());
+        p.setPen(QPen(QColor("green"),0.5));
+        stopPaintingAndSave(img, p, outputDir.absoluteFilePath("symbol_custom.png"));
     }
 
     if (listlinedecorators) {