Mechanics note 01 · rigid-body observation

Weight, friction, and a quiet fall.

A small stability bench for inspecting what a real collision solver does. Five deterministic loads meet a fixed support world; the page records the solver clock beside the rendered bodies.

Bench note SB—01 collision / balance
fixed Δt · 60 Hz

Observation / live stage

Let the bodies answer.

The viewport is a visual instrument only. Exact positions, units, and runtime state stay in the notebook and the table below.

Rapier stability bench · 3D stageseed 1608
Static evidence path Interactive runtime loading. If WebGL or WASM is unavailable, the body-state table remains the authoritative view. No animation is required to read the conditions below.
A fixed floor catches a deterministic stack. The blocks move only when Rapier advances the world. Camera, color, and grid are staging; the physical state is read from the table.

Readout / static parity

The table is the receipt.

Rows begin with the authored state and update from Rapier body transforms. A blocked renderer never removes this evidence.

Body state · metres in world coordinates
BodyRolePosition (x / y / z)State
floorfixed supportx 0.00 · y −1.20 · z 0.00 mfixed
backstopfixed guidex 0.00 · y 1.20 · z −1.75 mfixed
left guidefixed guidex −3.45 · y −0.45 · z 0.00 mfixed
right guidefixed guidex 3.45 · y −0.45 · z 0.00 mfixed
A / basedynamic loadx −0.60 · y 0.15 · z 0.00 mauthored
B / loaddynamic loadx 0.35 · y 0.85 · z 0.00 mauthored
C / loaddynamic loadx −0.30 · y 1.55 · z 0.00 mauthored
D / loaddynamic loadx 0.25 · y 2.25 · z 0.00 mauthored
E / topdynamic loadx −0.10 · y 2.95 · z 0.00 mauthored