Adding screenshot output to vtkchartwidget

radixwidgets/vtkchartwidget.cc

@@ -4,6 +4,9 @@ VTK_MODULE_INIT(vtkRenderingOpenGL2)
 VTK_MODULE_INIT(vtkInteractionStyle)
 VTK_MODULE_INIT(vtkRenderingFreeType)
 
+#include <vtkPNGWriter.h>
+#include <vtkWindowToImageFilter.h>
+
 #include "radixwidgets/vtkchartwidget.hh"
 
 namespace radix
@@ -33,4 +36,19 @@ vtkSmartPointer<vtkContextView> VTKChartWidget::contextView()
   return mContextView;
 }
 
+void VTKChartWidget::savePNG(QString outputFile)
+{
+  // Save the current view as a PNG file
+  vtkSmartPointer<vtkWindowToImageFilter> filter =
+      vtkSmartPointer<vtkWindowToImageFilter>::New();
+  filter->SetInput(mContextView->GetRenderWindow());
+  filter->ReadFrontBufferOff();
+  filter->Update();
+
+  vtkSmartPointer<vtkPNGWriter> writer = vtkSmartPointer<vtkPNGWriter>::New();
+  writer->SetFileName(outputFile.toStdString().c_str());
+  writer->SetInputConnection(filter->GetOutputPort());
+  writer->Write();
+}
+
 }  // namespace radix

radixwidgets/vtkchartwidget.hh

@@ -10,6 +10,8 @@
 #include <vtkRenderer.h>
 #include <vtkSmartPointer.h>
 
+#include <QString>
+
 #include "radixcore/visibility.hh"
 
 namespace radix
@@ -32,6 +34,10 @@ class RADIX_PUBLIC VTKChartWidget : public QVTKOpenGLWidget
   // Default values
   static double mDefaultBackground[3];
 
+ public slots:
+  // Save the current chart image as a PNG
+  void savePNG(QString outputFile);
+
  signals:
 
 };  // class VTKChartWidget