Geometry Nodes: Direct Bézier Handle Access for Grease Pencil
The problem
Geometry Nodes cannot directly edit Bézier handles on Grease Pencil strokes. Users must convert Grease Pencil → Curves → edit → convert back.
This workflow is:
- unnecessarily heavy
- destructive in edge cases (fills, topology, stroke nuance)
- unsuitable for procedural or real-time setups
This proposal requests direct access to Grease Pencil Bézier handle data in Geometry Nodes , removing the need for conversion.
More details
Without conversion, deformations (e.g. skew/shear) produce wobbly lines , because handles are not updated with control points.
Grease Pencil strokes can be Bézier-based, but in Geometry Nodes:
- handle data is not exposed
- curve handle nodes do not operate on GP
- conversion is the only workaround
Example:
A simple skew/shear system in Geometry Nodes
What's expected:
- offset points
- adjust handles to preserve curve shape
Again; what's requirement:
Grease Pencil
→ Grease Pencil to Curves
→ Realize Instances
→ Set Handle Positions
→ Curves to Grease Pencil
Issues:
- fill breakage in dense regions
- topology inconsistencies
- unnecessary performance cost
- overcomplicated node setups
Example artifact:
Note the missing collar fill, if I were to un-hide this other layers would lose their fill effect.
Avoiding conversion would remove the issue entirely.
This limitation blocks otherwise practical deformation workflows (e.g. skewing for animation).
Proposal
Allow Geometry Nodes to read and write Bézier handle data directly on Grease Pencil strokes .
Expose via either:
-
extending existing handle nodes to support Grease Pencil or
-
GP-specific nodes:
- Set Grease Pencil Handle Positions
- Set Grease Pencil Handle Type
Benefits
Non-destructive
- stable fills
- preserved stroke structure
- no reconstruction artifacts
Performance
- no instance realization
- no conversion overhead
Procedural animation
Enables GN-driven:
- skew / shear
- secondary motion
- rig-style deformation
Pipeline consistency
Supports workflows where:
- Grease Pencil is the primary format
- Geometry Nodes adds procedural control
- Skew/Shear Transformations are animated.
Expected Behavior
-
Operate directly on Grease Pencil stroke data
-
Affect Bézier curves only
-
Respect:
- layer selection
- frame/drawing context
-
Integrate with existing field system
Implementation Overview (high level)
-
Access writable Grease Pencil drawings during GN evaluation
-
Retrieve stroke data as curves (already internal)
-
Modify Bézier handle attributes (position/type)
-
Tag:
- position updates
- topology updates (if needed)
-
Respect shared drawing data (copy-on-write)
No user-facing data changes required.
So in short:
Grease Pencil already stores compatible curve data, and Geometry Nodes already edits Bézier handles.
This removes the gap between them.
Result:
- simpler node graphs
- better performance
- more reliable deformation
- stronger procedural 2D workflows
Further discussion on Blender artists including a copy of the blend file for testing:
blenderartists.org/t/skewing-shearing-gp-using-geo-nodes-bezier-handles-not-editable/1635115
-S
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