Classic API Resources Documentation

R23 API documentation includes a section concerning to the Classic API resources resulting by parsing the files located in {C4D Install Folder}/resource/modules/*.
The new content is located in Classic Resource overview .

The section enables browsing the Cinema 4D resources to find a particular ID for a given parameter or possible values for a Cycle parameter.

Scene Node

Scene Nodes is a technology preview of Cinema 4D future.
Due to the scope of the project, an API to directly access the provided functionalities is not yet available.
As a temporary fallback, it's possible to request and create a Classic API representation of the Scene Nodes output adopting the code below:

// Export Scene Nodes data BaseObject * scenenodesRoot = nullptr ; BaseSceneHook * scenenodes = doc->FindSceneHook( Int32 ( SCENENODES_IDS::SCENEHOOK_ID )); if (scenenodes == nullptr ) return maxon::UnexpectedError( MAXON_SOURCE_LOCATION );

// Request reference to Neutron objects before scene hook execution is done. scenenodes-> 消息 ( Int32 ( SCENENODES_IDS::MSGUPDATE_LEGACYOBJ_ID ), &scenenodesRoot); if (scenenodesRoot == nullptr ) return maxon::UnexpectedError( MAXON_SOURCE_LOCATION );

// Do anything with the sceneNodeRoot object. It's similar than BaseDocument::GetFirstObject(), but for the Scene Node Root.

For the time being, Scene Nodes Classic API representation only output PolygonObject , Null, LineObject and InstanceObject in Multi-Instances mode.
材质 applied via any 材质 node, will result in the creation of a TextureTag . Vertex Map will result in the creating of a VertexMapTag .
Dirty bit for these Classic API objects should be reliable. They also have unique hashes:

• Each Null in the hierarchy sets up the BaseObject::GetUniqueIP value to be a hash, but because that's only 32 bit, a collision is likely to occur for 2**16 clones (birthday paradox).
  The UInt64 PERSISTENT_HASH_LOW(SCENENODES_IDS::PERSISTENT_HASH_LOW_ID) is available in the data container to reduce the chances of collision.
• Multi-Instances (only available for Scene Node-created multi-instance) get a 128-bit hash for each instance that can be query by InstanceObject::GetInstancePersistentHashes .

It's worth to mention the activeobject.cpp example has been adapted to display Scene Nodes Classic API representation (see Project Hooks->Scene Nodes-> "CLASSIC_REPRESENTATION" within the plugin).

Execution Priorities

The EXECUTIONPRIORITY_SCENENODE has been added and it establishes a priority level higher than EXECUTIONPRIORITY_GENERATOR.

Array

A new maxon::Array template interface has been introduced. This new Array support COW (Copy-On-Write) reference and it allows to wrap any existing array-like implementation ( maxon::BaseArray , maxon::BlockArray ).

Scene Nodes uses this interface to access arrays (some PORT_BUNDLE have been replaced from BaseArray to Array).
However, rest assured the use of maxon::BaseArray , maxon::BlockArray is supported by Scene Nodes and conversion to the maxon::Array is granted using the maxon::ArrayFactory .

矩阵

The maxon::SqMat2, maxon::SqMat3 and maxon::SqMat4 structs have been renamed in maxon::SqrMat2 , maxon::SqrMat3 and maxon::SqrMat4 . This renaming does not affect the class member variables named "sqmat".

Limit<>::MAX/Limit<>::MIN

The maxon::Limit<>::MAX and maxon::Limit<>::MIN constants have been added for types in which they were missing and maxon::Limit<>::Max() and maxon::Limit<>::Min() have been replaced by the former two for types in which they were existing.

HashCode

Most of MAXON API elements such as maxon::MAXON_DATATYPE or Interface have now a GetHashCode method used to perform efficient comparison.
In R23 the implementation must return a maxon::HashInt and while, at the current time, a Uint64 is used, this may change to 128bits in the future without breaking compatibility.

The new DefaultHash class has a Combine function which allows combining HashInt values.

maxon::HashInt GetHashCode() const { maxon::DefaultHash hash; for ( const DescLevel & d : _subids) { hash. Combine ( maxon::DefaultCompare::GetHashCode (d.id)); } return hash;

// return maxon::DefaultHash::EMPTY_HASH in case of error. }