Uploaded August 2026 | Updated September 2026, 2 weeks ago
Unlock the full power of polygon editing in Blackmagic Fusion – without a single click on a UI slider.
In this tutorial, I walk you through two essential scripts I built for manipulating polylines and masks directly from the node’s comment field. Whether you’re a motion designer, compositor, or VFX artist, these tools will save you hours of tedious keyframe editing.
What you’ll learn:
- Reverse Polygon – Flip the direction of any polyline or mask path (open or closed) while keeping every keyframe intact. Perfect for reversing animation flows or fixing orientation issues.
- Divide Polygon – Subdivide every Bézier segment at its exact midpoint (t=0.5) using the De Casteljau algorithm. Add more control points without altering the curve shape – ideal for fine‑tuning or preparing a path for further deformation.
⚡ Key Features (both scripts)
✅ Works on static & animated polygons – all keyframes are processed automatically.
✅ Full support for closed & open paths – handles the first/last point correctly.
✅ Preserves tangents (handles) – left/right handles are swapped or recomputed so the curve stays perfectly smooth.
✅ No GUI, no clutter – just write parameters in the node’s comment field and run the script.
✅ Multi‑keyframe safe – changes are applied consistently across your entire animation.
✅ Free & Fusion‑native – runs in the free version of Fusion without any third‑party plugins.
🧠 Why these scripts are game‑changers
- For Reverse:
Inverting a polygon normally breaks keyframes or tangents. Our script maintains the exact same point indices – only the values are swapped, so your animation stays rock‑solid.
- For Divide:
Instead of guessing where to add points, the script uses De Casteljau’s subdivision to place a new point exactly on the curve, with handles inherited from the original segment. The result: more control, zero distortion.
🔗 Links & Resources
📁 Get the scripts here : elineau.gumroad.com/l/esluk
👨💻 Who is this for?
- Fusion users tired of manual point‑by‑point editing
- Anyone working with animated masks, motion paths, or vector shapes
- Scripters who want a clean, modular foundation for their own polygon tools
💬 Let’s connect
Drop a comment below if you’d like to see more polygon tools (Center, Straighten, Rounded, Barrel, Regularize…) or if you have a specific challenge in mind. I read every comment!
👍 Like if you found this useful
🔔 Subscribe for more Fusion scripting deep‑dives
📤 Share with your compositing buddies
#Fusion #DaVinciResolve #VFX #MotionDesign #Scripting #Polygon #Compositing #BlackmagicDesign #Lua #Procedural
Unlock the full power of polygon editing in Blackmagic Fusion – without a single click on a UI slider.
In this tutorial, I walk you through two essential scripts I built for manipulating polylines and masks directly from the node’s comment field. Whether you’re a motion designer, compositor, or VFX artist, these tools will save you hours of tedious keyframe editing.
What you’ll learn:
- Reverse Polygon – Flip the direction of any polyline or mask path (open or closed) while keeping every keyframe intact. Perfect for reversing animation flows or fixing orientation issues.
- Divide Polygon – Subdivide every Bézier segment at its exact midpoint (t=0.5) using the De Casteljau algorithm. Add more control points without altering the curve shape – ideal for fine‑tuning or preparing a path for further deformation.
⚡ Key Features (both scripts)
✅ Works on static & animated polygons – all keyframes are processed automatically.
✅ Full support for closed & open paths – handles the first/last point correctly.
✅ Preserves tangents (handles) – left/right handles are swapped or recomputed so the curve stays perfectly smooth.
✅ No GUI, no clutter – just write parameters in the node’s comment field and run the script.
✅ Multi‑keyframe safe – changes are applied consistently across your entire animation.
✅ Free & Fusion‑native – runs in the free version of Fusion without any third‑party plugins.
🧠 Why these scripts are game‑changers
- For Reverse:
Inverting a polygon normally breaks keyframes or tangents. Our script maintains the exact same point indices – only the values are swapped, so your animation stays rock‑solid.
- For Divide:
Instead of guessing where to add points, the script uses De Casteljau’s subdivision to place a new point exactly on the curve, with handles inherited from the original segment. The result: more control, zero distortion.
🔗 Links & Resources
📁 Get the scripts here : elineau.gumroad.com/l/esluk
👨💻 Who is this for?
- Fusion users tired of manual point‑by‑point editing
- Anyone working with animated masks, motion paths, or vector shapes
- Scripters who want a clean, modular foundation for their own polygon tools
💬 Let’s connect
Drop a comment below if you’d like to see more polygon tools (Center, Straighten, Rounded, Barrel, Regularize…) or if you have a specific challenge in mind. I read every comment!
👍 Like if you found this useful
🔔 Subscribe for more Fusion scripting deep‑dives
📤 Share with your compositing buddies
#Fusion #DaVinciResolve #VFX #MotionDesign #Scripting #Polygon #Compositing #BlackmagicDesign #Lua #Procedural
