FBX node attributes

Creating a node attribute

A FbxNodeAttribute is paired with a FbxNode to define a scene element with a specific position, rotation and scale. Calling FbxNode::GetNodeAttribute() will return NULL if no node attribute was set for that node.

The following code sample (adapted from ExportScene04/main.cxx to fit the diagram above) illustrates how to create a simple spotlight within a scene. Here, FbxLight* light is the node attribute of FbxNode* lightNode. For more information on lights, see ~{ Lights }~.

// Create a spotlight.
FbxNode* CreateLight(FbxScene* pScene, char* pName)
{
    FbxLight* light = FbxLight::Create(pScene,pName);

    light->LightType.Set(FbxLight::eSpot);
    light->CastLight.Set(true);

    FbxNode* lightNode = FbxNode::Create(pScene,pName);

    lightNode->SetNodeAttribute(light);

    return lightNode;
}

Node attributes

The following table presents a set of basic scene elements and their related FbxNodeAttribute subclasses. These node attributes can be paired with a FbxNode using FbxNode::SetNodeAttribute(). Consult the C++ Reference guide for the full class hierarchy.

Scene Element	`FbxNodeAttribute` subclass
Camera	`FbxCamera`, `FbxCameraStereo`
Camera Switcher (custom camera definition in Autodesk MotionBuilder)	`FbxCameraSwitcher`
Light	`FbxLight`
Mesh	`FbxMesh`
Nurb	`FbxNurbs`, `FbxNurbsCurve`, `FbxNurbsSurface`, `FbxTrimNurbsSurface`
Patch / Parametric Surface	`FbxPatch`
Level of Detail Group	`FbxLodGroup`
Marker	`FbxMarker`
Skeleton	`FbxSkeleton`

Note:

Some applications require a null node type in their scene graph. The FbxNull node attribute is used to define such a node type. Observe that an instance of FbxNull is not the same as the NULL value.

Node attribute type

The type (FbxNodeAttribute::EAttributeType) of a FbxNodeAttribute can be obtained by calling FbxNodeAttribute::GetAttributeType(). The EAttributeType is useful for downcasting the node attribute object to its appropriate subclass.

The following code sample (adapted from ImportScene/main.cxx and ImportScene/DisplayLight.cxx) illustrates how to use a switch to display a FbxLight contained in a FbxNode.

//
// Adapted from ImportScene/DisplayLight.cxx ...
// Display the various properties of the FbxLight contained within the FbxNode.
//
void DisplayLight(FbxNode* pNode)
{
    FbxLight* lLight = (FbxLight*) pNode->GetNodeAttribute();

    DisplayString("Light Name: ", (char *) pNode->GetName());
    // ...

    char* lLightTypes[] = { "Point", "Directional", "Spot" };

    DisplayString("    Type: ", lLightTypes[lLight->LightType.Get()]);
    DisplayBool("    Cast Light: ", lLight->CastLight.Get());

    if (!(lLight->FileName.Get().IsEmpty()))
    {
        DisplayString("    Gobo");

        DisplayString("        File Name: \"", lLight->FileName.Get().Buffer(), "\"");
        DisplayBool("        Ground Projection: ", lLight->DrawGroundProjection.Get());
        DisplayBool("        Volumetric Projection: ", lLight->DrawVolumetricLight.Get());
        DisplayBool("        Front Volumetric Projection: ", lLight->DrawFrontFacingVolumetricLight.Get());
    }

    // ...
}

//
// Adapted from ImportScene/main.cxx ...
// Display the contents of a node. Here, we are only interested in
// looking  at the eLight attribute type, which coincides with the
// FbxLight node attribute.
//
void DisplayContent(FbxNode* pNode)
{
    FbxNodeAttribute::EAttributeType lAttributeType;
    int i;

    if(pNode->GetNodeAttribute() == NULL)
    {
        printf("NULL Node Attribute\n\n");
    }
    else
    {
        lAttributeType = (pNode->GetNodeAttribute()->GetAttributeType());

        switch (lAttributeType)
        {
            // ...

        case FbxNodeAttribute::eLight:     
            DisplayLight(pNode);
            break;

            // ...
        }
    }

    // ...

    for(i = 0; i < pNode->GetChildCount(); i++)
    {
        DisplayContent(pNode->GetChild(i));
    }
}