Testing and visual QA

The differential harness that decides whether a change to the engine broke a picture, and the instrument that shows what the beat estimator was thinking. Both run on the same offscreen render path the shot CLI uses; this page is the contributor’s half of it.

Nothing here is needed to write a preset. What a preset author reaches for is Headless capture and video.

Sections

• The core/tests/ harness
• The habit for a new scene
• —downbeat-log: the estimator’s terms, one row per beat