Overview

The CRhinoGetObject class is used for selecting Rhino objects. When active, CRhinoGetObject object will allow the user to select objects either by picking them or by dragging a crossing window. But, using the SDK, it is possible to write your own object picking class or function. The heart of such a tool is the CRhinoPickContext which defines the rules for the picking. Once the rules have been defined, you can use CRhinoDoc::PickObjects to do the work.

Example

The following example code demonstrates how to drag a window to select objects.

  CRhinoCommand::result CCommandTest::RunCommand( const CRhinoCommandContext& context )
  {
    CRhinoGetPoint gp;
    gp.SetCommandPrompt( L"Drag a window to select objects" );
    gp.SetGetPointCursor( RhinoApp().m_default_cursor );
    gp.ConstrainToTargetPlane();
    CRhinoGet::result res = gp.Get2dRectangle( 0, 0, FALSE, PS_DOT );
    if( res != CRhinoGet::rect2d )
      return failure;


    CRect pick_rect = gp.Rectangle2d();
    CRhinoView* view = gp.View();


    CRhinoPickContext pick_context;
    pick_context.m_go = 0;
    pick_context.m_view = view;
    pick_context.m_pick_style = CRhinoPickContext::window_pick;
    pick_context.m_bPickGroups = true;
    switch( view->Viewport().DisplayMode() )
    {
      case ON::shaded_display:
      case ON::renderpreview_display:
        pick_context.m_pick_mode = CRhinoPickContext::shaded_pick;
        break;
    }


    CRhinoObjRefArray pick_list;
    int pick_count = 0;
    if( view->Viewport().GetPickXform(pick_rect, pick_context.m_pick_region.m_xform) )
    {
      pick_context.UpdateClippingPlanes();
      POINT screen_point = pick_rect.BottomRight();
      view->ActiveViewport().VP().GetFrustumLine( screen_point.x, screen_point.y, pick_context.m_pick_line );
      int i, pick_count = context.m_doc.PickObjects( pick_context, pick_list );
      for( i = 0; i < pick_count; i++ )
      {
        const CRhinoObject* obj = pick_list[i].Object();
        if( obj && obj->IsSelectable() )
          obj->Select( true );
      }
      if( pick_count )
        context.m_doc.Redraw();
    }


    return success;
  }