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Precise Physics is a PhysX Painter tool that places one object per click or spacing interval at the cursor position, raises it above the surface by a fixed offset, then drops it using physics simulation. Unlike Brush Physics, which scatters many objects across a brush area using the Scatter system, Precise Physics places exactly one object per interaction with no scatter distribution — you control the exact placement point.
New to Precise Physics? Follow the step-by-step Precise Physics — Getting Started tutorial first.

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Supported resource types

Precise Physics supports:

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How it works

  1. You click or drag in the scene view. The tool casts a ray downward at the cursor position.
  2. A random prototype is selected from the active group based on Success weights.
  3. The prototype is instantiated at the ray hit point offset upward by Position Offset Y.
  4. Physics simulation starts immediately in acceleration mode. The object falls, collides with the terrain and other colliders, and is frozen when physics settles.
  5. The Physics Effects force is applied to the spawned rigidbody at spawn time.
  6. The scene view shows a small sphere handle above the hit point to indicate where the object will spawn.

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Tool-level settings

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Precise Physics Tool Settings

  • Spacing — the minimum cursor travel distance (in world units) before a new placement fires while dragging. Default: 5. Minimum: 0.5. Lower values place objects more densely when you drag; higher values space them further apart.
  • Position Offset Y — how far above the surface hit point the object is spawned before falling. Default: 30. Adjust this based on the size of your objects and how much fall height you want.

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Physics Effects

Controls the initial impulse applied to each spawned object. See Physics Effects Settings for all fields.

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Prototype-level settings

Each prototype in the group has:
  • Success — controls the probability that a given prototype is selected.
  • Physics Transform Settings — transform components applied before the object enters physics simulation.

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When to use Precise Physics

Precise Physics is best when you want to:
  • place a single object at a deliberate point and let physics determine its final resting pose;
  • add individual props one at a time in a targeted location;
  • use physics settling for exact placements rather than broad scatter strokes.

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Notes

  • The tool belongs to the PhysX Painter family.
  • No Scatter system is involved — one object is placed per interaction.
  • The physics simulator uses acceleration physics mode and ObjectTimeDisablePhysicsMode.
  • Undo is registered after mouse release.
  • The scene view marker is a colored sphere handle offset above the cursor hit point by the current Position Offset Y value.