Please refer to the project  "Editor"  which is located in the SeeDraw Samples folder.

 

// Render background object.

fDrawCtrl1.Document.RefreshQuick(false);

// Move the current vertex to other position.

m_object.SetWindowVertex(curnodeIdx, new SeeDraw.sdGeometry.Point2D(e.X, e.Y));

// Redraw the object 

fDrawCtrl1.Document.RenderGraphic.DrawEntity(m_object);

// Update all the entities that Drawn by DrawEntity to the screen.

fDrawCtrl1.Document.UpdateScene();

 

Fast refresh can only be used in the condition that the 

background is a static drawing !!!