feat(Align): add component, demo, docs

docs/.vitepress/config.ts

@@ -158,6 +158,7 @@ export default defineConfig({
           { text: 'Precipitation', link: '/guide/staging/precipitation' },
           { text: 'Sparkles', link: '/guide/staging/sparkles' },
           { text: 'Ocean', link: '/guide/staging/ocean' },
+          { text: 'Align', link: '/guide/staging/align' },
           { text: 'SoftShadows', link: '/guide/staging/soft-shadows' },
           { text: 'Grid', link: '/guide/staging/grid' },
         ],

docs/.vitepress/theme/components/AlignDemo.vue

@@ -0,0 +1,20 @@
+<script setup lang="ts">
+import { Align, OrbitControls } from '@tresjs/cientos'
+import { TresCanvas } from '@tresjs/core'
+</script>
+
+<template>
+  <TresCanvas clear-color="#222">
+    <TresPerspectiveCamera />
+    <OrbitControls />
+
+    <TresAxesHelper :scale="2" />
+
+    <Align top right back>
+      <TresMesh>
+        <TresBoxGeometry />
+        <TresMeshNormalMaterial />
+      </TresMesh>
+    </Align>
+  </TresCanvas>
+</template>

docs/component-list/components.ts

@@ -108,6 +108,7 @@ export default [
       { text: 'Sparkles', link: '/guide/staging/sparkles' },
       { text: 'Ocean', link: '/guide/staging/ocean' },
       { text: 'Fit', link: '/guide/staging/fit' },
+      { text: 'Align', link: '/guide/staging/align' },
       { text: 'SoftShadows', link: '/guide/staging/soft-shadows' },
       { text: 'Grid', link: '/guide/staging/grid' },
     ],

docs/guide/staging/align.md

@@ -0,0 +1,51 @@
+# Align
+
+<DocsDemo>
+  <AlignDemo />
+</DocsDemo>
+
+Calculates a bounding box around its children and aligns them as a group within their parent. The component measures its contents and realigns on every frame unless `cacheKey` is set.
+
+## Usage
+
+<<< @/.vitepress/theme/components/AlignDemo.vue
+
+## Props
+
+All props are optional.
+
+| Prop         | Description                         |
+| ------------ | ----------------------------------- |
+| `top`        | If `true`, aligns bounding box bottom to `0` on the y-axis |
+| `bottom`     | If `true`, aligns bounding box top to `0` on the y-axis. |
+| `left`       | If `true`, aligns bounding box right to `0` on the x-axis. |
+| `right`      | If `true`, aligns bounding box left to `0` on the x-axis. |
+| `front`      | If `true`, aligns bounding box back to `0` on the z-axis. |
+| `back`       | If `true`, aligns bounding box front to `0` on the z-axis. |
+| `disable`    | If `true`, disables alignment on all axes. |
+| `disableX`   | If `true`, disables alignment on the x-axis. |
+| `disableY`   | If `true`, disables alignment on the y-axis. |
+| `disableZ`   | If `true`, disables alignment on the z-axis. |
+| `precise`    | See [Box3.setFromObject](https://threejs.org/docs/index.html?q=box3#api/en/math/Box3.setFromObject). |
+| `onAlign`    | Callback that fires when updating, after measurement. |
+| `cacheKey`   | If set, component will only update when `cacheKey`'s value changes. If unset, component will update every frame. |
+
+## `OnAlignCallbackProps`
+
+```ts
+export interface OnAlignCallbackProps {
+  /** The next parent above <Align /> */
+  parent: Object3D
+  /** The outmost container group of the <Align /> component */
+  container: Object3D
+  width: number
+  height: number
+  depth: number
+  boundingBox: Box3
+  boundingSphere: Sphere
+  center: Vector3
+  verticalAlignment: number
+  horizontalAlignment: number
+  depthAlignment: number
+}
+```

playground/vue/src/pages/staging/AlignDemo.vue

@@ -0,0 +1,61 @@
+<script setup lang="ts">
+import { Align, OrbitControls } from '@tresjs/cientos'
+import { TresCanvas } from '@tresjs/core'
+import { TresLeches, useControls } from '@tresjs/leches'
+import '@tresjs/leches/styles'
+
+const elapsed = shallowRef(0)
+let intervalId: ReturnType<typeof setInterval>
+onMounted(() => {
+  intervalId = setInterval(() => {
+    elapsed.value += 1000 / 30
+  }, 1000 / 30)
+})
+
+onUnmounted(() => {
+  clearInterval(intervalId)
+})
+
+const ctrl = useControls({
+  top: false,
+  left: false,
+  front: false,
+  bottom: false,
+  right: false,
+  back: false,
+  disable: false,
+  disableX: false,
+  disableY: false,
+  disableZ: false,
+  useCacheKey: false,
+  vIf: true,
+})
+</script>
+
+<template>
+  <TresLeches />
+  <TresCanvas>
+    <TresPerspectiveCamera :position="[0, 0, 5]" />
+    <OrbitControls />
+    <TresAxesHelper :scale="2" :position="[0, 0, 0]" />
+    <Align
+      v-if="ctrl.vIf.value.value"
+      :left="ctrl.left.value.value"
+      :right="ctrl.right.value.value"
+      :top="ctrl.top.value.value"
+      :bottom="ctrl.bottom.value.value"
+      :front="ctrl.front.value.value"
+      :back="ctrl.back.value.value"
+      :disable="ctrl.disable.value.value"
+      :disable-x="ctrl.disableX.value.value"
+      :disable-y="ctrl.disableY.value.value"
+      :disable-z="ctrl.disableZ.value.value"
+      :cache-key="ctrl.useCacheKey.value.value ? (() => Math.floor(elapsed * 0.001)) : undefined"
+    >
+      <TresMesh :position-x="Math.cos(elapsed * 0.001) * 2" :position-y="Math.sin(elapsed * 0.001) * 2" :scale-z="Math.cos(elapsed * 0.001) * 2">
+        <TresBoxGeometry />
+        <TresMeshNormalMaterial />
+      </TresMesh>
+    </Align>
+  </TresCanvas>
+</template>

playground/vue/src/router/routes/staging.ts

@@ -49,6 +49,11 @@ export const stagingRoutes = [
     name: 'Fit',
     component: () => import('../../pages/staging/fit/index.vue'),
   },
+  {
+    path: '/staging/align',
+    name: 'Align',
+    component: () => import('../../pages/staging/AlignDemo.vue'),
+  },
   {
     path: '/staging/soft-shadows',
     name: 'SoftShadows',

src/core/staging/Align.vue

@@ -0,0 +1,142 @@
+<script setup lang="ts">
+import { useLoop } from '@tresjs/core'
+import type { Group, Object3D } from 'three'
+import { Box3, Sphere, Vector3 } from 'three'
+import type { MaybeRefOrGetter } from 'vue'
+import { shallowRef, toValue, watchEffect } from 'vue'
+
+// NOTE: Sources
+// https://github.com/pmndrs/drei/blob/master/src/core/Center.tsx
+
+export interface OnAlignCallbackProps {
+  /** The next parent above <Align /> */
+  parent: Object3D
+  /** The outmost container group of the <Align/> component */
+  container: Object3D
+  width: number
+  height: number
+  depth: number
+  boundingBox: Box3
+  boundingSphere: Sphere
+  center: Vector3
+  verticalAlignment: number
+  horizontalAlignment: number
+  depthAlignment: number
+}
+
+export interface AlignProps {
+  top?: boolean
+  right?: boolean
+  bottom?: boolean
+  left?: boolean
+  front?: boolean
+  back?: boolean
+  /** Disable all axes */
+  disable?: boolean
+  /** Disable x-axis alignment */
+  disableX?: boolean
+  /** Disable y-axis alignment */
+  disableY?: boolean
+  /** Disable z-axis alignment */
+  disableZ?: boolean
+  /** See https://threejs.org/docs/index.html?q=box3#api/en/math/Box3.setFromObject */
+  precise?: boolean
+  /** Callback, fires when updating, after measurement */
+  onAlign?: (props: OnAlignCallbackProps) => void
+  /** Optional cacheKey to keep the component from recalculating on every render */
+  cacheKey?: MaybeRefOrGetter<any>
+}
+
+const props = withDefaults(defineProps<AlignProps>(), {
+  precise: true,
+  cacheKey: undefined,
+})
+
+const ref = shallowRef<Group>()
+const outer = shallowRef<Group>()
+const inner = shallowRef<Group>()
+
+const box3 = new Box3()
+const center = new Vector3()
+const sphere = new Sphere()
+
+function update() {
+  if (!outer.value || !inner.value || !ref.value) { return }
+  outer.value.matrixWorld.identity()
+  box3.setFromObject(inner.value, props.precise)
+  const width = box3.max.x - box3.min.x
+  const height = box3.max.y - box3.min.y
+  const depth = box3.max.z - box3.min.z
+  box3.getCenter(center)
+  box3.getBoundingSphere(sphere)
+  const yAlign = props.top ? height / 2 : props.bottom ? -height / 2 : 0
+  const xAlign = props.left ? -width / 2 : props.right ? width / 2 : 0
+  const zAlign = props.front ? depth / 2 : props.back ? -depth / 2 : 0
+
+  outer.value.position.set(
+    props.disable || props.disableX ? 0 : -center.x + xAlign,
+    props.disable || props.disableY ? 0 : -center.y + yAlign,
+    props.disable || props.disableZ ? 0 : -center.z + zAlign,
+  )
+
+  // Only fire onCentered if the bounding box has changed
+  if (typeof props.onAlign !== 'undefined') {
+    props.onAlign({
+      parent: ref.value.parent!,
+      container: ref.value,
+      width,
+      height,
+      depth,
+      boundingBox: box3,
+      boundingSphere: sphere,
+      center,
+      verticalAlignment: yAlign,
+      horizontalAlignment: xAlign,
+      depthAlignment: zAlign,
+    })
+  }
+}
+
+let off: (() => void) | null = null
+let cacheKey: any = null
+
+// NOTE: `useLoop` requires TresContext, which is only
+// availble in setup. We need a handle in useEffect,
+// so keep a reference.
+const loop = useLoop()
+
+watchEffect(() => {
+  // NOTE: update whenever cachekey changes.
+
+  // NOTE: We might already always be updating, so `off`.
+  off?.()
+  off = null
+
+  // NOTE: Don't update if we resolve to the previous cacheKey value,
+  // unless cacheKey is null or undefined.
+  const nextKey = toValue(props.cacheKey)
+  if (nextKey === cacheKey && cacheKey !== null && cacheKey !== undefined) { return }
+  cacheKey = nextKey
+
+  if (props.cacheKey === null || props.cacheKey === undefined) {
+    off = loop.onBeforeRender(() => {
+      update()
+    }).off
+  }
+  else {
+    update()
+  }
+})
+
+defineExpose({ instance: ref, update })
+</script>
+
+<template>
+  <TresGroup ref="ref">
+    <TresGroup ref="outer">
+      <TresGroup ref="inner">
+        <slot></slot>
+      </TresGroup>
+    </TresGroup>
+  </TresGroup>
+</template>

src/core/staging/index.ts

@@ -1,3 +1,4 @@
+import Align from './Align.vue'
 import Backdrop from './Backdrop.vue'
 import ContactShadows from './ContactShadows.vue'
 import Fit from './Fit.vue'
@@ -13,6 +14,7 @@ import Environment from './useEnvironment/component.vue'
 import Lightformer from './useEnvironment/lightformer/index.vue'
 
 export {
+  Align,
   Backdrop,
   ContactShadows,
   Environment,