Add files from zip

playground/vectorfield/main.cpp

@@ -0,0 +1,120 @@
+/*****************************************************************************
+ * Qwt Examples - Copyright (C) 2002 Uwe Rathmann
+ * This file may be used under the terms of the 3-clause BSD License
+ *****************************************************************************/
+
+#include <QwtPlot>
+#include <QwtVectorFieldSample>
+#include <QwtPlotVectorField>
+#include <QwtVectorFieldArrow>
+#include <QwtPlotGrid>
+#include <QwtLegend>
+#include <QwtColorMap>
+
+#include <QApplication>
+#include <QPen>
+
+namespace
+{
+    class VectorField : public QwtPlotVectorField
+    {
+      public:
+        VectorField()
+            : QwtPlotVectorField( "Vector Field" )
+        {
+            setRenderHint( QwtPlotItem::RenderAntialiased, true );
+            setLegendIconSize( QSize( 20, 10 ) );
+
+            setMagnitudeScaleFactor( 1.0 );
+
+#if 0
+            // test solid arrow
+            setSymbol( new QwtVectorFieldArrow() );
+            setPen( Qt::NoPen );
+            setBrush( Qt::black );
+            setMagnitudeScaleFactor( 2 );
+#endif
+
+#if 1
+            // test color map
+            QwtLinearColorMap* cm = new QwtLinearColorMap();
+            cm->setColorInterval( Qt::yellow, Qt::blue );
+            cm->addColorStop( 0.5, Qt::red );
+            setColorMap( cm );
+            setMagnitudeMode( MagnitudeAsColor, true );
+#endif
+
+#if 1
+            setIndicatorOrigin( QwtPlotVectorField::OriginHead );
+#else
+            setIndicatorOrigin( QwtPlotVectorField::OriginTail );
+#endif
+
+#if 0
+            setRasterSize( QSizeF( 20, 20 ) );
+#endif
+            setSamples( samples() );
+        }
+
+      private:
+        QVector< QwtVectorFieldSample > samples() const
+        {
+            const int dim = 10;
+
+            QVector< QwtVectorFieldSample > samples;
+
+            for ( int x = -dim; x < dim; x++ )
+            {
+                for ( int y = -dim; y < dim; y++ )
+                {
+                    samples += QwtVectorFieldSample( x, y, y, -x );
+                }
+            }
+
+            return samples;
+        }
+    };
+
+    class Plot : public QwtPlot
+    {
+      public:
+        Plot()
+        {
+            setTitle( "Vector Field" );
+            setCanvasBackground( Qt::white );
+
+            insertLegend( new QwtLegend() );
+
+            QwtPlotGrid* grid = new QwtPlotGrid();
+            grid->attach( this );
+
+            VectorField* fieldItem = new VectorField();
+            fieldItem->attach( this );
+
+            const QRectF r = fieldItem->boundingRect();
+
+#if 1
+            setAxisScale( QwtAxis::XBottom, r.left() - 1.0, r.right() + 1.0 );
+#else
+            setAxisScale( QwtAxis::XBottom, r.right() + 1.0, r.left() - 1.0 );
+#endif
+
+#if 1
+            setAxisScale( QwtAxis::YLeft, r.top() - 1.0, r.bottom() + 1.0 );
+#else
+            setAxisScale( QwtAxis::YLeft, r.bottom() + 1.0, r.top() - 1.0 );
+#endif
+        }
+    };
+}
+
+int main( int argc, char* argv[] )
+{
+    QApplication app( argc, argv );
+
+    Plot plot;
+    plot.resize( 600, 400 );
+    plot.show();
+
+    return app.exec();
+}