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@threlte/theatre

<Sync>

Use the component <Sync> from the <SheetObject> slot prop to automatically pick up properties from its parent.

<SheetObject>
  {#snippet children({ Sync })}
    <T.MeshBasicMaterial>
      <Sync
        color
        roughness
        rotation
      />
    </T.MeshBasicMaterial>
  {/snippet}
</SheetObject>

Special Properties Note that some properties are treated differently. The rotation prop and

other properties with type THREE.Euler are automatically converted from radians to degrees. Properties like color which have a type of THREE.Color receive a color picker in the studio automatically.

Labeled Prop

To label an auto prop, just provide a string instead of a boolean value.

<script>
  import { T } from '@threlte/core'
  import { SheetObject } from '@threlte/theatre'
</script>

<SheetObject key="cube">
  {#snippet children({ Sync })}
    <T.Mesh>
      <T.BoxGeometry />
      <T.MeshStandardMaterial>
        <!-- labeled prop: rename color to tone in the studio -->
        <Sync color="tone" />
      </T.MeshStandardMaterial>
    </T.Mesh>
  {/snippet}
</SheetObject>

Pierced Prop

Similarly to the pierced props of <T>, the props of the component <Sync> can be anotated in the same fashion.

<script>
  import { T } from '@threlte/core'
  import { SheetObject } from '@threlte/theatre'
</script>

<SheetObject key="cube">
  {#snippet children({ Sync })}
    <T.Mesh>
      <!-- pierced prop: edit only x coord. in the studio -->
      <Sync position.x />
      <T.BoxGeometry />
      <T.MeshStandardMaterial />
    </T.Mesh>
  {/snippet}
</SheetObject>

Transformers

The component <Sync> uses transformers to provide the best possible editing experience in the Theatre.js studio based on the type of the property. Sometimes this is not desireable and you may want to go further. One example is the property intensity on lights. By default, it’s a regular numerical input, but in practice it makes sense to have a range slider that lets you select numbers from 0 to e.g. 10.

To create a transformer that can be reused, you are provided a utility function:

import { createTransformer } from '@threlte/theatre'
import { types } from '@theatre/core'

const intensity = createTransformer({
  transform(value) {
    return types.number(value, {
      range: [0, 10]
    })
  },
  apply(target, path, value) {
    target[path] = value
  }
})

The transform function is used to transform the value of a certain Three.js objects proerty to a property that Theatre.js can use in an ISheetObject. To ensure compatibility with the rest of the package, the return value must be any one of the functions available at Theatre.js’ types.

The apply function is used to apply the value to the target. target is the parent object of the property (usually a Three.js object), path is the name of the property and value is the value to apply.

You may also declare transformers directly in the markup:

<script>
  import { T } from '@threlte/core'
  import { SheetObject } from '@threlte/theatre'
  import { createTransformer, types } from '@threlte/theatre'
</script>

<SheetObject key="light">
  {#snippet children({ Sync })}
    <T.DirectionalLight>
      <Sync
        intensity={{
          transformer: {
            transform(value) {
              // use the initial value and provide a range
              // slider UI that goes from 0 to 2.
              return types.number(value, {
                range: [0, 2]
              })
            },
            apply(target, path, value) {
              // whenever the value changes, apply it back
              // to the target.
              target[path] = value
            }
          }
        }}
      />
    </T.DirectionalLight>
  {/snippet}
</SheetObject>

Built-in components use transformers internally

<Sync> uses transformers to transform arbitrary props that are discovered by a property path to a value that Theatre.js can handle. <Transform> uses transformers to transform the properties position, rotation and scale of a Three.js object to a value that Theatre.js can handle.

Component Signature

Props

name
type
required

type
any
no