Creating a Custom Color Picker

This guide demonstrates how to replace Rhino's color picker using C/C++.

How To

To replace Rhino’s color picking dialog, derive a new class from CRhinoReplaceColorDialog and override the ColorDialog() virtual function. Note, if more that one CRhinoReplaceColorDialog-derived classes exist, then the last CRhinoReplaceColorDialog-derived object created will be displayed.

The following sample code demonstrates how to replace Rhino’s color picking dialog. In this example, we will simply replace it with the Windows standard color picking dialog…

class CMyColorDialog : public CRhinoReplaceColorDialog
  CMyColorDialog() : CRhinoReplaceColorDialog(::AfxGetStaticModuleState()) {};
  virtual ~CMyColorDialog() {};
  bool CMyColorDialog::ColorDialog( HWND hWndParent,
                                    ON_Color& color,
                                    bool bIncludeButtonColors,
                                    const wchar_t* lpsDialogTitle )
    CColorDialog dlg( color, CC_ANYCOLOR|CC_FULLOPEN, CWnd::FromHandle(hWndParent) );
    if( IDOK != dlg.DoModal() )
      return false;
    color = dlg.GetColor();
    return true;

Now, create a new Rhino command and add a pointer to the above class as a public data member. Do not forget to initialize it’s value to NULL in the command classes constructor. For example:

CMyColorDialog* m_pMyColorDialog;
// ...
CTestCommand::CTestCommand() : pMyColorDialog(NULL) {}

Finally, in your new command classes RunCommand() member, install the new color picker. For example:

CRhinoCommand::result CCommandTest::RunCommand( const CRhinoCommandContext& context )
  if( m_pMyColorDialog )
    delete m_pMyColorDialog;
    m_pMyColorDialog = NULL;
    RhinoApp().Print( L"Rhino color dialog restored.\n" );
    m_pMyColorDialog = new CMyColorDialog;
    if( m_pMyColorDialog )
      RhinoApp().Print( L"Rhino color dialog replaced.\n" );
      RhinoApp().Print( L"Error replacing Rhino color dialog.\n" );
  return CRhinoCommand::success;

For more information on the CRhinoReplaceColorDialog class, see it’s declaration in rhinoSdkUtilities.h.