How to use Attributes

Generalities about entity attributes

You can retrieve attributes from many Datakit objects, any class inheriting from Dtk_Entity or Dtk_DocElement being eligible.
This includes various data :

• General : name, color, visibility, layer informations
• Metadata : PDM file properties, generic custom properties (named values)
• Rendering : Surface lighting and texturing information.
• Material : Definition of physical properties of used material (name, density, conductivity, strength...)

Common entities on which attributes can be found are :

• Dtk_Component
• Dtk_Node
• Dtk_Body
• Topological entities such as Dtk_Face, Dtk_Edge, Dtk_Vertex
• Geometrical entities such as Dtk_Surface, Dtk_Curve, etc.
  Those attributes are stored in Dtk_Info of the entity. See Dtk_DocElement::GetInfos() and Dtk_Entity::get_info().
  The sample below allows you to retrieve common graphical attributes from a Dtk_Node.

Sample code

Dtk_NodePtr layerInfoSetNode;
Dtk_LayerInfosSetPtr layerSet = layerInfoSetNode->GetDtk_LayerInfosSetPtr();
Dtk_NodePtr inNode;
 
/* Get Dtk_InfoPtr class */
Dtk_InfoPtr infos = inNode->GetInfos(); 
 
/* Retrieve inNode blanked status  : -1 = undefined, 0 = Visible, 1=Invisible, 2=Construction Geometry */
int NodeBlankedStatus = infos->GetBlankedStatus();
 
/* Retrieve inNode activation status  :  1 = Activated (Shown), 0 = Disable (Not Shown)*/
int ActivationStatus = infos->GetActivationFlag();
 
/* Retrieve inNode name */
Dtk_string name = infos->GetName();
 
/* Retrieve inNode color RGB */
Dtk_RGB color = infos->GetColor();
 
/* Retrieve inNode layer */
int layer = infos->GetLayer();     
 
/* Retrieve inNode layer name */
Dtk_string layerName;
Dtk_LayerInfosSet::Layer out; 
auto error = layerSet.GetLayerByID( layer, out );
if ( error == dtkNoError )
     layerName = out.GetName();
 
/* Retrieve inNode list of layer it appears in */
Dtk_tab<Dtk_Int32> layer = infos->GetlayerList();
 
 
/* Retrieve inNode render information (Lights, texture data) */
Dtk_RenderInfosPtr render = infos->GetRenderInfos();
Dtk_DumpXml_Dtk_RenderInfos(render);

Focus on layers

Calling Dtk_Info::GetLayer() provides a layer identifier, of which the entity belong.
For format allowing an entity to be listed in multiples layers, Dtk_Info::GetlayerList() allow to retrieve the list of layers the entity belong to.
If the said entity appears in only one layer, this call is equivalent to Dtk_Info::GetLayer().

In case the format allows more information relative to layers, such as name assignment or layer filtering, Dtk_LayerInfosSet allows to retrieve those information.
They live in the context of a Dtk_Component.
See Dtk_LayerFilterInfos and Dtk_LayerInfosSet interface and detailed description for more information.

Dtk_LayerInfosSet sample code

/* Set creation */
Dtk_LayerInfosSetPtr in = Dtk_LayerInfosSet::Create();//Creates a layer set.
in->AddLayer( Dtk_LayerInfosSet::Layer( 42, L"42" ) );
in->AddLayer( Dtk_LayerInfosSet::Layer( 50, L"Layer fifty" ) );
in->AddLayer( Dtk_LayerInfosSet::Layer( 1025 ) );
in->SetCurrentLayer( 2 ); //The layer with index 2 becomes the current layer.
 
auto const& createdFilter = in->CreateLayerFilterInfos( L"simple filter", L"A simple filter", DTK_FALSE, DTK_TRUE );//Creates a filter that is the default, where none of the set's layers are selected.
createdFilter->SelectLayer( 1 );
createdFilter->SelectLayer( 2 );
 
/* Browse through layers */
 
for ( Dtk_LayerInfosSet::Layer layer : in.GetLayers() )
{
     Dtk_string LayerName = layer.GetName();
     Dtk_ID LayerID = layer.GetID();
}
 
/* Find a specific layer */
Dtk_LayerInfosSet::Layer layerWithID50;
auto status = in->GetLayerByID( 50, layerWithID50 );//Get layer with ID 50
if( status != dtkNoError )
     std::cout << "Layer 50 not found" << std::endl;
else
     std::cout << layerWithID50.GetName() << std::endl;//prints "Layer fifty"
 
/* Find current layer */
Dtk_Size_t currentIndex = 0;
Dtk_Size_t indexCount = 0;
status = in->GetCurrentLayer( currentIndex );
if( status == dtkNoError )
{
     for ( Dtk_LayerInfosSet::Layer layer :  in.GetLayers() )
     {
          if( indexCount == currentIndex )   
               std::cout << layer.GetID() << std::endl; //prints 1025
          indexCount++;
     }
 
 
}
 
/* Browse through layer filters */
for( Dtk_Size_t i = 0; i < in->GetNumLayerFilters(); ++i )
{
     auto const& filter = in->GetLayerFilterByPos( i );
 
     Dtk_tab<Dtk_Size_t> outIndexes;
     filter->GetSelectedLayers( outIndexes );
     for( Dtk_Size_t j = 0; j < outIndexes.size(); ++j )
     {
          Dtk_string selectedLayerName; Dtk_ID selectedLayerID;
          in->GetLayerName( outIndexes[ j ], selectedLayerName );
          in->GetLayerID( outIndexes[ j ], selectedLayerID );
     }
}
 
/* Find default layer filter */
Dtk_Size_t defaultFilterIndex = 0;
Dtk_string defaultFilterLayerName, defaultFilterLayerDescription;
status = in->GetDefaultLayerFilter( defaultFilterIndex );
if( status == dtkNoError )
{
     auto const& defaultFilter = in->GetLayerFilterByPos( defaultFilterIndex );
     defaultFilter->GetName( defaultFilterLayerName );
     defaultFilter->GetDescription( defaultFilterLayerDescription );
     std::cout << defaultFilterLayerName << " : " << defaultFilterLayerDescription << std::endl;//prints "simple filter : A simple filter"
}