Added new functionalities to viz module

- load OBJ file
- set offscreen rendering
- set roll angle of the camera
- get Mat screenshot of the current scene
- remove all lights from the scene
- add a custom light in the scene
- modify the size of the WImage3D widget
- added ambient property for the widget

Changed Vec3d in cv::viz::Color

Renamed method getMatScreenshotin getScreenshot

Modified showWidget

Fixed on viz::Color and reverted fix on vtkProp3D

Removed cameraRoll method

Merged load mesh method (for ply and obj file)

Fixed doc

Fixed cv::viz::WImage3D::setSize for vtk5.8

Fixed enum for cv::viz::Mesh::load

modules/viz/src/precomp.hpp

@@ -130,6 +130,7 @@
 #include <vtkElevationFilter.h>
 #include <vtkColorTransferFunction.h>
 #include <vtkStreamingDemandDrivenPipeline.h>
+#include <vtkLight.h>
 #include "vtkCallbackCommand.h"
 
 #if !defined(_WIN32) || defined(__CYGWIN__)

modules/viz/src/shapes.cpp

@@ -728,6 +728,24 @@ void cv::viz::WImage3D::setImage(InputArray image)
     actor->SetTexture(texture);
 }
 
+void cv::viz::WImage3D::setSize(const cv::Size& size)
+{
+    vtkSmartPointer<vtkActor> actor = vtkActor::SafeDownCast(WidgetAccessor::getProp(*this));
+    vtkSmartPointer<vtkPolyDataMapper> mapper = vtkPolyDataMapper::SafeDownCast(actor->GetMapper());
+    vtkSmartPointer<vtkTextureMapToPlane> textured_plane;
+    vtkSmartPointer<vtkPlaneSource> plane;
+    #if VTK_MAJOR_VERSION <= 5
+        textured_plane = vtkTextureMapToPlane::SafeDownCast(mapper->GetInputConnection(0,0)->GetProducer());
+        plane = vtkPlaneSource::SafeDownCast(textured_plane->GetInputConnection(0,0)->GetProducer());
+    #else
+        textured_plane = vtkTextureMapToPlane::SafeDownCast(mapper->GetInputAlgorithm());
+        plane = vtkPlaneSource::SafeDownCast(textured_plane->GetInputAlgorithm());
+    #endif
+    plane->SetOrigin(-0.5 * size.width, -0.5 * size.height, 0.0);
+    plane->SetPoint1( 0.5 * size.width, -0.5 * size.height, 0.0);
+    plane->SetPoint2(-0.5 * size.width,  0.5 * size.height, 0.0);
+}
+
 template<> cv::viz::WImage3D cv::viz::Widget::cast<cv::viz::WImage3D>()
 {
     Widget3D widget = this->cast<Widget3D>();

modules/viz/src/types.cpp

@@ -57,11 +57,35 @@ cv::viz::MouseEvent::MouseEvent(const Type& _type, const MouseButton& _button, c
 ////////////////////////////////////////////////////////////////////
 /// cv::viz::Mesh3d
 
-cv::viz::Mesh cv::viz::Mesh::load(const String& file)
+cv::viz::Mesh cv::viz::Mesh::load(const String& file, int type)
 {
-    vtkSmartPointer<vtkPLYReader> reader = vtkSmartPointer<vtkPLYReader>::New();
-    reader->SetFileName(file.c_str());
-    reader->Update();
+    vtkSmartPointer<vtkPolyDataAlgorithm> reader = vtkSmartPointer<vtkPolyDataAlgorithm>::New();
+    switch (type) {
+      case LOAD_AUTO:
+      {
+        CV_Assert(!"cv::viz::Mesh::LOAD_AUTO: Not implemented yet");
+        break;
+      }
+      case LOAD_PLY:
+      {
+        vtkSmartPointer<vtkPLYReader> ply_reader = vtkSmartPointer<vtkPLYReader>::New();
+        ply_reader->SetFileName(file.c_str());
+        ply_reader->Update();
+        reader = ply_reader;
+        break;
+      }
+      case LOAD_OBJ:
+      {
+        vtkSmartPointer<vtkOBJReader> obj_reader = vtkSmartPointer<vtkOBJReader>::New();
+        obj_reader->SetFileName(file.c_str());
+        obj_reader->Update();
+        reader = obj_reader;
+        break;
+      }
+      default:
+        CV_Assert(!"cv::viz::Mesh::load: Unknown file type");
+        break;
+    }
 
     vtkSmartPointer<vtkPolyData> polydata = reader->GetOutput();
     CV_Assert("File does not exist or file format is not supported." && polydata);

modules/viz/src/viz3d.cpp

@@ -100,6 +100,10 @@ void cv::viz::Viz3d::release()
 
 void cv::viz::Viz3d::spin() { impl_->spin(); }
 void cv::viz::Viz3d::spinOnce(int time, bool force_redraw) { impl_->spinOnce(time, force_redraw); }
+void cv::viz::Viz3d::setOffScreenRendering() { impl_->setOffScreenRendering(); }
+void cv::viz::Viz3d::removeAllLights() { impl_->removeAllLights(); }
+void cv::viz::Viz3d::addLight(Vec3d position, Vec3d focalPoint, Color color, Color diffuseColor, Color ambientColor, Color specularColor)
+{  impl_->addLight(position, focalPoint, color, diffuseColor, ambientColor, specularColor);  }
 bool cv::viz::Viz3d::wasStopped() const { return impl_->wasStopped(); }
 void cv::viz::Viz3d::close() { impl_->close(); }
 
@@ -134,6 +138,7 @@ void cv::viz::Viz3d::converTo3DRay(const Point3d &window_coord, Point3d &origin,
 cv::Size cv::viz::Viz3d::getWindowSize() const { return impl_->getWindowSize(); }
 void cv::viz::Viz3d::setWindowSize(const Size &window_size) { impl_->setWindowSize(window_size); }
 cv::String cv::viz::Viz3d::getWindowName() const { return impl_->getWindowName(); }
+cv::Mat cv::viz::Viz3d::getScreenshot() const { return impl_->getScreenshot(); }
 void cv::viz::Viz3d::saveScreenshot(const String &file) { impl_->saveScreenshot(file); }
 void cv::viz::Viz3d::setWindowPosition(const Point& window_position) { impl_->setWindowPosition(window_position); }
 void cv::viz::Viz3d::setFullScreen(bool mode) { impl_->setFullScreen(mode); }

modules/viz/src/vizimpl.cpp

@@ -68,6 +68,8 @@ cv::viz::Viz3d::VizImpl::VizImpl(const String &name) : spin_once_state_(false),
     exit_callback_ = vtkSmartPointer<ExitCallback>::New();
     exit_callback_->viz = this;
 
+    offScreenMode_ = false;
+
     setBackgroundMeshLab();
 }
 
@@ -187,6 +189,38 @@ void cv::viz::Viz3d::VizImpl::spinOnce(int time, bool force_redraw)
     local->DestroyTimer(timer_callback_->timer_id);
 }
 
+/////////////////////////////////////////////////////////////////////////////////////////////
+void cv::viz::Viz3d::VizImpl::setOffScreenRendering()
+{
+    window_->SetOffScreenRendering(1);
+    offScreenMode_ = true;
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////////
+void cv::viz::Viz3d::VizImpl::removeAllLights()
+{
+    renderer_->RemoveAllLights();
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////////
+void cv::viz::Viz3d::VizImpl::addLight(Vec3d position, Vec3d focalPoint, Color color, Color diffuseColor, Color ambientColor, Color specularColor)
+{
+    Color color_  = vtkcolor(color);
+    Color diffuseColor_ = vtkcolor(diffuseColor);
+    Color ambientColor_ = vtkcolor(ambientColor);
+    Color specularColor_ = vtkcolor(specularColor);
+
+    vtkSmartPointer<vtkLight> light = vtkSmartPointer<vtkLight>::New();
+    light->SetPosition(position.val);
+    light->SetFocalPoint(focalPoint.val);
+    light->SetColor(color_.val);
+    light->SetDiffuseColor(diffuseColor_.val);
+    light->SetAmbientColor(ambientColor_.val);
+    light->SetSpecularColor(specularColor_.val);
+
+    renderer_->AddLight(light);
+}
+
 /////////////////////////////////////////////////////////////////////////////////////////////
 void cv::viz::Viz3d::VizImpl::showWidget(const String &id, const Widget &widget, const Affine3d &pose)
 {
@@ -293,6 +327,39 @@ cv::Affine3d cv::viz::Viz3d::VizImpl::getWidgetPose(const String &id) const
 /////////////////////////////////////////////////////////////////////////////////////////////
 void cv::viz::Viz3d::VizImpl::saveScreenshot(const String &file) { style_->saveScreenshot(file.c_str()); }
 
+/////////////////////////////////////////////////////////////////////////////////////////////
+cv::Mat cv::viz::Viz3d::VizImpl::getScreenshot() const
+{
+    vtkSmartPointer<vtkWindowToImageFilter> windowToImageFilter =
+        vtkSmartPointer<vtkWindowToImageFilter>::New();
+    windowToImageFilter->SetInput(window_);
+    windowToImageFilter->ReadFrontBufferOff(); // read from the back buffer
+    windowToImageFilter->Update();
+
+    vtkImageData *resultImage = windowToImageFilter->GetOutput();
+    int * dim  = resultImage->GetDimensions();
+    cv::Mat image(dim[1], dim[0], CV_8UC3);
+
+    Vec3b* dptr = reinterpret_cast<Vec3b*>(resultImage->GetScalarPointer());
+    size_t elem_step = resultImage->GetIncrements()[1]/sizeof(Vec3b);
+
+    for (int y = 0; y < image.rows; ++y)
+    {
+        const Vec3b* drow = dptr + elem_step * y;
+        unsigned char *srow = image.ptr<unsigned char>(image.rows - y - 1);
+        for (int x = 0; x < image.cols; ++x, srow += image.channels())
+        {
+          srow[0] = drow[x][2];
+          srow[1] = drow[x][1];
+          srow[2] = drow[x][0];
+        }
+    }
+
+    resultImage = 0;
+
+    return image;
+}
+
 /////////////////////////////////////////////////////////////////////////////////////////////
 void cv::viz::Viz3d::VizImpl::registerMouseCallback(MouseCallback callback, void* cookie)
 { style_->registerMouseCallback(callback, cookie); }

modules/viz/src/vizimpl.hpp

@@ -62,6 +62,10 @@ public:
 
     void spin();
     void spinOnce(int time = 1, bool force_redraw = false);
+    void setOffScreenRendering();
+
+    void removeAllLights();
+    void addLight(Vec3d position, Vec3d focalPoint, Color color, Color diffuseColor, Color ambientColor, Color specularColor);
 
     void showWidget(const String &id, const Widget &widget, const Affine3d &pose = Affine3d::Identity());
     void removeWidget(const String &id);
@@ -89,6 +93,7 @@ public:
     void convertToWindowCoordinates(const Point3d &pt, Point3d &window_coord);
     void converTo3DRay(const Point3d &window_coord, Point3d &origin, Vec3d &direction);
 
+    Mat getScreenshot() const;
     void saveScreenshot(const String &file);
     void setWindowPosition(const Point& position);
     Size getWindowSize() const;
@@ -131,6 +136,8 @@ private:
     vtkSmartPointer<vtkVizInteractorStyle> style_;
     Ptr<WidgetActorMap> widget_actor_map_;
 
+    bool offScreenMode_;
+
     bool removeActorFromRenderer(vtkSmartPointer<vtkProp> actor);
     void recreateRenderWindow();
 };

modules/viz/src/widget.cpp

@@ -114,6 +114,7 @@ void cv::viz::Widget::setRenderingProperty(int property, double value)
         case OPACITY:             actor->GetProperty()->SetOpacity(value);          break;
         case LINE_WIDTH:          actor->GetProperty()->SetLineWidth(float(value)); break;
         case IMMEDIATE_RENDERING: actor->GetMapper()->SetImmediateModeRendering(int(value)); break;
+        case AMBIENT:             actor->GetProperty()->SetAmbient(float(value)); break;
         case FONT_SIZE:
         {
             vtkTextActor* text_actor = vtkTextActor::SafeDownCast(actor);