Weight Painting Studio

The WEIGHTS tab (and in-viewport Weight Painting Studio, hotkey R) provides interactive 3D vertex weight painting directly inside the Unreal Engine level editor viewport.

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1. Paint Targets

Dynamic Wind Studio supports dual deformation paint layers:

• Target 1: Skin (Bone):
  • Paints standard vertex skinning weights assigned to the currently selected skeletal bone.
  • Controls how strongly each vertex deforms when joints rotate under wind forces.
• Target 2: Wind Pin:
  • Defines the global wind anchoring mask across the model:
    • 0.0 (Black): Completely pinned / anchored to the world (e.g., tree roots, banner wall mounts, cable posts).
    • 1.0 (White): Fully unconstrained, dynamic movement.
    • Values between 0.0 and 1.0 create smooth stiffness transitions along trunk and branch lengths.

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2. Brush Operations & Controls

• Brush Modes:
  • Add: Incrementally increases weight values up to 1.0.
  • Subtract: Reduces weight values down to 0.0.
  • Smooth: Blurs and averages weight transitions across neighboring vertices to eliminate hard creases.
  • Set: Instantly paints an absolute weight value defined by the Value slider.
• Brush Settings:
  • Paint Strength: Controls the opacity and speed of weight application per stroke.
  • Brush Radius: 3D spherical radius of the brush in world units.
  • Only Paint Inside Selected Part: When checked, strokes will never bleed or spill onto adjacent parts (e.g., painting leaves without accidentally touching the trunk).

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3. Quick Weight Actions

• Apply to Selection: Instantly assigns the current paint value to all currently selected triangles.
• Smooth Weights: Runs a global Laplacian smoothing pass across the active target layer.
• Clear Target: Clears all painted weights on the active layer back to default.
• Clear All Paint: Reverts mesh skinning to procedural studio-generated weights.

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Next: 04. Wind Dynamics & Solvers Workflow →