vtkBoxWidget2 shows a bounding box outline, the face of the box can be picked and moved to scale the object inside the bounding box. After rotating, translating, and scaling, we can ensure the inside item change shape and position with the box widget. It sounds so good that user can Read more…
The article shows a few kinds of widgets which are used to measure the distance between two points, angle between two rays, and the bidimensional length of an object. Distance Measure The Distance On 2D Model We need vtkDistanceWidget, vtkDistanceRepresentation2D and vtkPointHandleRepresentation2D to help us to calculate the distance between Read more…
We want to put points on the three-dimensional model sometimes, it’s better if these control points can be moved around the item and project generates a new interpolation line dynamically. VTK provides a tool for us to do it easily. The following content shows two scenarios about point placer, both Read more…
The article shows how to create a simple vtk render window project. We need cmake and the visualization toolkit installed. This example uses C plus plus programming language to create and show a cone in the 3D world. CMakeLists.txt cmake_minimum_required(VERSION 2.8) project(mytest) find_package( VTK REQUIRED ) include( ${VTK_USE_FILE} ) add_executable(${PROJECT_NAME} Read more…
The filter vtkWarpScalar can help us to move the point along point normal by the scalar amount times the scale factor. We can change the size of the original model with it as long as there are normals in data. The following example has two renderers, the left renderer shows Read more…
We can use VTK observer-command mechanism to listen to slider value changing event and override our responding method void Execute(vtkObject *caller, unsigned long, void*) to change target item’s size. It’s easy to implement with the subclass of vtkCommand and vtkSliderWidget. The following example shows how to do it. I add Read more…
AddInputConnection is a public interface provided by vtkAlgorithm. We can use it to combine multiple input sources to get a final 3D model with some special algorithm class. The following example has two VTK algorithm classes which show us the multiple source connections. int main() { vtkSmartPointer<vtkSphereSource> sphereSource = vtkSmartPointer<vtkSphereSource>::New(); Read more…
vtkInteractorEventRecorder can be used to record VTK events in a single file and replay it by pass these events to vtkRenderWindowInteractor. Record The following code shows how to use it to save all interactive information into a file. We rotate the cone and switch its surface status between wireframe and Read more…
vtkAbstractWidget has its mechanism to handle interactive events. Here is a simple demo indicates the differences between the responses of widget and vtkInteractorStyleTrackballCamera. Example Code: int main() { vtkSmartPointer<vtkConeSource> cone = vtkSmartPointer<vtkConeSource>::New(); cone->Update(); vtkSmartPointer<vtkPolyDataMapper> coneMapper = vtkSmartPointer<vtkPolyDataMapper>::New(); coneMapper->SetInputData( cone->GetOutput() ); coneMapper->Update(); vtkSmartPointer<vtkActor> coneActor = vtkSmartPointer<vtkActor>::New(); coneActor->SetMapper( coneMapper ); vtkSmartPointer<vtkPointHandleRepresentation3D> handleRep Read more…