Setup engine options

// Assuming 'resmgr' is the cluster's resource manager, 'window' is a window object, 'viewpoint1'
// and 'viewpoint2' are two viewpoints inserted into 'window'.

// Accessing the 'window' option interface:
RED::IOptions* iwinopt = window->As< RED::IOptions >();
// Modifying a display option:
RC_TEST( iwinopt->SetOptionValue( RED::OPTIONS_SHADOW_MAP_DEPTH, 3, iresmgr->GetState() ) );

// Modifying the same option for 'viewpoint1':
RED::IOptions* iv1opt = viewpoint1->As< RED::IOptions >();
RC_TEST( iv1opt->SetOptionValue(  RED::OPTIONS_SHADOW_MAP_DEPTH, 0, iresmgr->GetState() ) );

For the example above, 'window' has two child viewpoints named 'viewpoint1' and 'viewpoint2'. The RED::OPTIONS_SHADOW_MAP_DEPTH is set to 3 at the window level, and to 0 on 'viewpoint1'. Consequently, 'viewpoint1' will be rendered with a value of 0 for the option, and 'viewpoint2' will be rendered with a value of 3 for the option, due to the inheritance model.