A 3D Slicer module introducing a new displayable manager architecture for layered rendering and interaction handling.
SlicerLayerDisplayableManager is an experimental module designed to simplify the integration of new display pipelines in 3D Slicer. It introduces a flexible and extensible framework for managing layered rendering, interaction forwarding, and camera synchronization across multiple pipelines.
This module aims to address common limitations in existing displayable managers by offering a more modular and injectable design.
- Factorize pipeline creation and teardown
- Enable layered rendering and interaction forwarding
- Maintain focus continuity across pipelines
- Synchronize cameras across views and layers
- Centralize render request handling
The current displayable manager (DM) architecture in 3D Slicer presents several structural and usability limitations:
- Redundant logic: Each DM reimplements pipeline instantiation and renderer setup independently.
- Custom camera sync: Camera synchronization strategies are manually implemented per DM, leading to inconsistent behavior.
- Complexity growth: DMs tend to accumulate unrelated logic over time, making them harder to maintain and extend.
- Focus handling: Focus decisions are based on proximity to interaction only, without consideration for layer priority.
- Factory instantiation: DMs are created using string-based factories, preventing injection of shared dependencies or services.
The module introduces a new architecture to improve development quality and scalability for visualization widgets:
- Centralized pipeline management: Pipelines are automatically created and deleted by the displayable manager.
- Dependency injection: Lambda and callback-based creators allow find pipeline creation control and injection of shared logic at pipeline creation.
- Modular camera synchronization: A dedicated synchronizer handles camera updates across views and layers for pipelines following the main camera.
- Layer-aware interaction: Pipelines declare their render layer with arbitrary values, enabling prioritized focus and interaction handling without handling the finer grained VTK logic.
- Python integration: A Python abstract class enables rapid development and integration of pipelines.
These changes simplify the development of new widgets, reduce boilerplate, and improve maintainability of existing visualization components.
- Pipeline registration via factory and creator API
- Lambda and callback support for dependency injection
- Customizable observer update pattern
- First-class Python abstract pipeline class
WARNING : Experimental Module
API may change or break between versions. Under review by the 3D Slicer community for potential core integration.
| Class | Description |
|---|---|
| vtkMRMLLayerDMPipelineI | Interface for display pipelines. Handles interaction, rendering, camera, and observer logic. |
| vtkMRMLLayerDisplayableManager | Main displayable manager. Initializes pipeline manager and delegates scene updates. |
| vtkMRMLLayerDMCameraSynchronizer | Synchronizes default camera with renderer or slice node state. |
| vtkMRMLLayerDMLayerManager | Manages renderer layers based on pipeline layer/camera pairs. |
| vtkMRMLLayerDMPipelineCreatorI | Interface for pipeline creation. Supports custom instantiation logic. |
| vtkMRMLLayerDMPipelineCallbackCreator | Callback-based implementation of pipeline creator. |
| vtkMRMLLayerDMPipelineScriptedCreator | Python lambda-based pipeline creator. |
| vtkMRMLLayerDMPipelineFactory | Singleton factory for pipeline instantiation and registration. |
| vtkMRMLLayerDMPipelineManager | Manages pipeline lifecycle, layer manager, and camera sync. |
| vtkMRMLLayerDMScriptedPipelineBridge | Python bridge for virtual method delegation. |
| vtkMRMLLayerDMScriptedPipeline | Python abstract class for scripted pipelines. |
New() -> vtkMRMLLayerDMPipelineI*
CanProcessInteractionEvent(vtkMRMLInteractionEventData* eventData, double& distance2) -> bool
GetCamera() const -> vtkCamera*
GetMouseCursor() const -> int
GetRenderOrder() const -> unsigned int
GetWidgetState() const -> int
LoseFocus(vtkMRMLInteractionEventData* eventData) -> void
OnDefaultCameraModified(vtkCamera* camera) -> void
OnRendererAdded(vtkRenderer* renderer) -> void
OnRendererRemoved(vtkRenderer* renderer) -> void
ProcessInteractionEvent(vtkMRMLInteractionEventData* eventData) -> bool
SetDisplayNode(vtkMRMLNode* displayNode) -> void
SetPipelineManager(vtkMRMLLayerDMPipelineManager* pipelineManager) -> void
SetScene(vtkMRMLScene* scene) -> void
SetViewNode(vtkMRMLAbstractViewNode* viewNode) -> void
UpdatePipeline() -> void
BlockResetDisplay(bool isBlocked) -> bool
GetDisplayNode() const -> vtkMRMLNode*
GetNodePipeline(vtkMRMLNode* node) const -> vtkMRMLLayerDMPipelineI*
GetRenderer() const -> vtkRenderer*
GetScene() const -> vtkMRMLScene*
GetViewNode() const -> vtkMRMLAbstractViewNode*
UpdateObserver(vtkObject* prevObj, vtkObject* obj, const std::vector<unsigned long>& events) const -> bool
UpdateObserver(vtkObject* prevObj, vtkObject* obj, unsigned long event) const -> bool
ResetDisplay() -> void
RequestRender() const -> void
SetRenderer(vtkRenderer* renderer) -> void
vtkMRMLLayerDMPipelineI()
~vtkMRMLLayerDMPipelineI()
OnUpdate(vtkObject* obj, unsigned long eventId, void* callData) -> void- Python pipelines can be created using
from LayerDMLib.vtkMRMLLayerDMScriptedPipeline import vtkMRMLLayerDMScriptedPipeline - Scripted creators allow dynamic injection of pipeline logic
- Ideal for prototyping and rapid development
This module is under active development and experimentation. Contributions and feedback from the 3D Slicer community are welcome to refine its design and promote future integration into the core.
To use this module:
- Register your pipeline using the factory API
- Implement your pipeline logic via
vtkMRMLLayerDMPipelineIor its Python counterpart - Inject your creator using callback or scripted creator
- Let the displayable manager handle the rest