# Motion pass

> Read every cut of the draft at full size, fix what reads flat, and write one row for each cut in the brief.

Canonical: https://vawe.dev/docs/motion-pass

At the end of this page the draft has no flat cut, and the three motion checks are clean or waived with a reason. The brief has a filled “Motion pass”. This is stage 7 of the <Term id="loop">loop</Term>.

You need a full draft from [Draft](https://vawe.dev/docs/draft). The strip verbs read the last full draft, so a range draft does not count.

## Steps

<Steps>
  <Step>
    ### Read the motion checks

    The draft prints these. Each one is clean, or the page declares a <Term id="waiver">waiver</Term> with a reason that names a world or a second and a measured number.

    | Check             | The rule                                                                                                                                              |
    | ----------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- |
    | `overshoot-share` | 21 to 61 percent of the arrivals that move overshoot. About 1 in 3 lands with a spring (`EASE.pop`). Type, UI and counts do not overshoot by default. |
    | `live-hold`       | No span over 0.5 s outside a declared hold where no part of the frame moves by itself. A camera drift does not count.                                 |
    | `constant-camera` | The camera moves for 60 percent of the film or less. It holds still by default.                                                                       |
    | `seam-variety`    | Each moving seam changes axis or direction from the one before. A hard cut is exempt.                                                                 |
  </Step>

  <Step>
    ### Strip every cut

    ```bash
    bin/vawe strip films/hello/page.html --cuts
    ```

    This writes one strip for each <Term id="world">world</Term> change, centred on the <Term id="cut">cut</Term>. Read each grid at full size. Look at how the outgoing part and the incoming part overlap.
  </Step>

  <Step>
    ### Look closer at the spectacle second

    ```bash
    bin/vawe strip films/hello/page.html --at 2.75 --onion
    bin/vawe strip films/hello/page.html --at 2.75 --velocity
    ```

    `--onion` blends several frames of one move into one image: the newest is the strongest, and older frames are fainter. It shows the spacing, the path and the overshoot. `--velocity` graphs the speed and scale of the elements that move most, with the start, peak, settle and overshoot of each. `--sel` picks elements by a CSS selector. `--velocity` reads a page only.
  </Step>

  <Step>
    ### Check each cut against the principles

    For each cut, check these points: anticipation on the hero, follow-through and overlap, eased spacing, and arcs on travelling elements. Also check secondary action, exits faster than entrances, and holds alive through element motion. The camera stays still unless it is the spectacle. The sources are `taste/craft/motion-craft.md` and `core/motion/README.md`.
  </Step>

  <Step>
    ### Fix what reads flat

    Edit the page. Render only the seconds you changed.

    ```bash
    bin/vawe dev films/hello/page.html --from 2 --to 4
    bin/vawe strip films/hello/page.html --at 2.75
    ```
  </Step>

  <Step>
    ### Write one row for each cut

    In `brief.md`, fill the “Motion pass” section with one row for each cut: each principle you checked, what read flat and what you fixed. The `next:` line asks for this while the section is empty.
  </Step>
</Steps>

## What you see

Each `strip` run prints the path of an image. A grid also gives the seconds when the move starts, peaks and settles. `--onion` writes to `out/onion/<film>` and `--velocity` writes a PNG to `out/velocity`.

<Figure src="loop/strip-cut.webp" alt="A grid of frames through the cut at 1.53 s of colour-sting." caption="vawe strip --cuts: the frames through one cut, with its motion numbers." width="1566" height="882" />

<Figure src="loop/onion.webp" alt="Six frames of one move blended into one image, older frames fainter." caption="vawe strip --onion: the path, spacing and overshoot of one move." width="960" height="608" />

<Figure src="loop/velocity.webp" alt="A graph of speed and scale over time for the moving element at the cut." caption="vawe strip --velocity: start, peak and settle of each moving element." width="1200" height="760" />

## What good looks like

* The hold is not frozen. One part moves in every hold (a line typing, a counter, a glint), not the camera.
* A hero arrival overshoots. Most others land on a soft stop.
* Two moving seams in a row do not go the same way.
* Every row of “Motion pass” names a cut and a fix. The example is the last section of `films/examples/colour-sting/brief.md`.

## Common mistakes

| What you see                               | Why                                                            | What to do                                                                     |
| ------------------------------------------ | -------------------------------------------------------------- | ------------------------------------------------------------------------------ |
| `strip --cuts` finds no cuts               | The page has no `data-world` elements, or no full draft exists | Add the elements, then run `bin/vawe dev`                                      |
| A camera drift in every hold               | You tried to fix `live-hold` with the camera                   | Give the hold an element motion instead, and keep the camera for the spectacle |
| `ship` warns that the Motion pass is empty | The section still has its placeholder row                      | Write the rows; the warning is advice and does not stop the render             |

## What to read next

  <Card title="Critique and fix" href="/docs/critique">
    Stages 8 and 9: a fresh session looks at the draft.
  </Card>

  <Card title="Motion" href="/docs/motion">
    Eases, springs and the moves.
  </Card>

{/* sources (vawe d8481cc61):
  stage order and rows: AGENTS.md loop table row 7; harness/live/stage-say.mjs (SAY.motion, SAY.motionRows)
  strip, --onion, --velocity flags: bin/vawe strip --help
  rules: taste/rules/overshoot.md, taste/rules/live-hold.md, taste/rules/constant-camera.md, taste/rules/seam-variety.md
  principles list: harness/live/stage-say.mjs (SAY.motion)
  Motion pass section and ship warning: harness/lib/board.mjs (motionFilled, shipWarnings)
  strip reads the last full draft: bin/vawe strip --help
  */}