refactor: Change zoom pane into viewport

* split zoom pane into smaller components as viewport
* rename UseZoomPanHelper Type to Viewport

package/src/composables/useZoomPanHelper.ts

@@ -2,13 +2,13 @@ import { zoomIdentity } from 'd3-zoom'
 import useVueFlow from './useVueFlow'
 import useWindow from './useWindow'
 import { getRectOfNodes, pointToRendererPoint, getTransformForBounds } from '~/utils'
-import { GraphNode, Store, UseZoomPanHelper, D3Selection } from '~/types'
+import { GraphNode, Store, Viewport, D3Selection } from '~/types'
 
 const DEFAULT_PADDING = 0.1
 
 const transition = (selection: D3Selection, ms = 0) => selection.transition().duration(ms)
 
-export default (store: Store = useVueFlow().store): UseZoomPanHelper => ({
+export default (store: Store = useVueFlow().store): Viewport => ({
   zoomIn: (options) => store.d3Selection && store.d3Zoom?.scaleBy(transition(store.d3Selection, options?.duration), 1.2),
   zoomOut: (options) => store.d3Selection && store.d3Zoom?.scaleBy(transition(store.d3Selection, options?.duration), 1 / 1.2),
   zoomTo: (zoomLevel, options) =>

package/src/container/TransformationPane/TransformationPane.vue → package/src/container/Viewport/Transform.vue

@@ -33,7 +33,7 @@ const transform = computed(() => `translate(${store.transform[0]}px,${store.tran
 </script>
 <script lang="ts">
 export default {
-  name: 'TransformationPane',
+  name: 'Transform',
 }
 </script>
 <template>

package/src/container/Viewport/Viewport.vue

@@ -0,0 +1,53 @@
+<script lang="ts" setup>
+import { zoom } from 'd3-zoom'
+import { select } from 'd3-selection'
+import { useVueFlow } from '../../composables'
+import SelectionPane from '../SelectionPane/SelectionPane.vue'
+import Zoom from './Zoom.vue'
+import Transform from './Transform.vue'
+
+const { id, store } = useVueFlow()
+const zoomPaneEl = templateRef<HTMLDivElement>('viewport', null)
+
+const { width, height } = useElementBounding(zoomPaneEl)
+
+useResizeObserver(zoomPaneEl, () => {
+  store.dimensions.width = width.value
+  store.dimensions.height = height.value
+})
+
+const d3Zoom = ref()
+const d3Selection = ref()
+const d3ZoomHandler = ref()
+onMounted(() => {
+  d3Zoom.value = zoom<HTMLDivElement, any>().scaleExtent([store.minZoom, store.maxZoom]).translateExtent(store.translateExtent)
+  d3Selection.value = select(zoomPaneEl.value).call(d3Zoom.value)
+  d3ZoomHandler.value = d3Selection.value.on('wheel.zoom')
+
+  store.setState({
+    d3Zoom: d3Zoom.value,
+    d3Selection: d3Selection.value,
+    d3ZoomHandler: d3ZoomHandler.value,
+  })
+})
+</script>
+<script lang="ts">
+export default {
+  name: 'Viewport',
+}
+</script>
+<template>
+  <div ref="viewport" class="vue-flow__viewport vue-flow__container">
+    <Zoom
+      v-if="d3Zoom && d3Selection && d3ZoomHandler"
+      :d3-zoom="d3Zoom"
+      :d3-selection="d3Selection"
+      :d3-zoom-handler="d3ZoomHandler"
+    >
+      <Transform>
+        <slot />
+      </Transform>
+    </Zoom>
+    <SelectionPane :key="`selection-pane-${id}`" />
+  </div>
+</template>

package/src/container/Viewport/Zoom.vue

@@ -0,0 +1,152 @@
+<script lang="ts" setup>
+import { D3ZoomEvent, zoomIdentity, ZoomTransform } from 'd3-zoom'
+import { pointer } from 'd3-selection'
+import { useKeyPress, useVueFlow } from '../../composables'
+import { D3Selection, D3Zoom, D3ZoomHandler, FlowTransform, PanOnScrollMode } from '../../types'
+import { clamp, clampPosition } from '../../utils'
+
+interface Props {
+  d3Zoom: D3Zoom
+  d3Selection: D3Selection
+  d3ZoomHandler: D3ZoomHandler
+}
+
+const props = defineProps<Props>()
+
+const { store } = useVueFlow()
+
+const viewChanged = (prevTransform: FlowTransform, eventTransform: ZoomTransform): boolean =>
+  (prevTransform.x !== eventTransform.x && !isNaN(eventTransform.x)) ||
+  (prevTransform.y !== eventTransform.y && !isNaN(eventTransform.y)) ||
+  (prevTransform.zoom !== eventTransform.k && !isNaN(eventTransform.k))
+
+const eventToFlowTransform = (eventTransform: ZoomTransform): FlowTransform => ({
+  x: eventTransform.x,
+  y: eventTransform.y,
+  zoom: eventTransform.k,
+})
+
+const isWrappedWithClass = (event: Event, className: string | undefined) => (event.target as Element).closest(`.${className}`)
+
+const clampedZoom = clamp(store.defaultZoom, store.minZoom, store.maxZoom)
+const transform = ref({
+  ...clampPosition({ x: store.defaultPosition[0], y: store.defaultPosition[1] }, store.translateExtent),
+  zoom: clampedZoom,
+})
+
+const updatedTransform = zoomIdentity.translate(transform.value.x, transform.value.y).scale(transform.value.zoom)
+props.d3Zoom.transform(props.d3Selection, updatedTransform)
+
+store.transform = [updatedTransform.x, updatedTransform.y, updatedTransform.k]
+
+const selectionKeyPressed = useKeyPress(store.selectionKeyCode, (keyPress) => {
+  if (keyPress) {
+    props.d3Zoom.on('zoom', null)
+  } else {
+    props.d3Zoom.on('zoom', (event: D3ZoomEvent<HTMLDivElement, any>) => {
+      store.setState({ transform: [event.transform.x, event.transform.y, event.transform.k] })
+      const flowTransform = eventToFlowTransform(event.transform)
+      store.hooks.move.trigger({ event, flowTransform })
+    })
+  }
+})
+
+const zoomKeyPressed = useKeyPress(store.zoomActivationKeyCode)
+
+props.d3Zoom.on('start', (event: D3ZoomEvent<HTMLDivElement, any>) => {
+  const flowTransform = eventToFlowTransform(event.transform)
+  transform.value = flowTransform
+  store.hooks.moveStart.trigger({ event, flowTransform })
+})
+
+props.d3Zoom.on('end', (event: D3ZoomEvent<HTMLDivElement, any>) => {
+  if (viewChanged(transform.value, event.transform)) {
+    const flowTransform = eventToFlowTransform(event.transform)
+    transform.value = flowTransform
+    store.hooks.moveEnd.trigger({ event, flowTransform })
+  }
+})
+
+props.d3Selection
+  ?.on('wheel', (event: WheelEvent) => {
+    if (store.panOnScroll && !zoomKeyPressed.value) {
+      if (isWrappedWithClass(event, store.noWheelClassName)) return
+      event.preventDefault()
+      event.stopImmediatePropagation()
+
+      const currentZoom = props.d3Selection?.property('__zoom').k || 1
+
+      if (event.ctrlKey && store.zoomOnPinch) {
+        const point = pointer(event)
+        // taken from https://github.com/d3/d3-zoom/blob/master/src/zoom.js
+        const pinchDelta = -event.deltaY * (event.deltaMode === 1 ? 0.05 : event.deltaMode ? 1 : 0.002) * 10
+        const zoom = currentZoom * Math.pow(2, pinchDelta)
+        if (props.d3Selection) props.d3Zoom.scaleTo(props.d3Selection, zoom, point)
+
+        return
+      }
+
+      // increase scroll speed in firefox
+      // firefox: deltaMode === 1; chrome: deltaMode === 0
+      const deltaNormalize = event.deltaMode === 1 ? 20 : 1
+      const deltaX = store.panOnScrollMode === PanOnScrollMode.Vertical ? 0 : event.deltaX * deltaNormalize
+      const deltaY = store.panOnScrollMode === PanOnScrollMode.Horizontal ? 0 : event.deltaY * deltaNormalize
+
+      if (props.d3Selection && store.panOnScrollSpeed)
+        props.d3Zoom?.translateBy(
+          props.d3Selection,
+          -(deltaX / currentZoom) * store.panOnScrollSpeed,
+          -(deltaY / currentZoom) * store.panOnScrollSpeed,
+        )
+    } else {
+      if (
+        (!store.zoomOnScroll && store.preventScrolling) ||
+        !store.preventScrolling ||
+        isWrappedWithClass(event, store.noWheelClassName)
+      )
+        return null
+      event.preventDefault()
+    }
+  })
+  .on('wheel.zoom', store.panOnScroll || typeof props.d3ZoomHandler === 'undefined' ? null : (props.d3ZoomHandler as any))
+
+props.d3Zoom.filter((event: MouseEvent) => {
+  console.log(event)
+  const zoomScroll = zoomKeyPressed.value || store.zoomOnScroll
+  const pinchZoom = store.zoomOnPinch && event.ctrlKey
+
+  // if all interactions are disabled, we prevent all zoom events
+  if (!store.panOnDrag && !zoomScroll && !store.panOnScroll && !store.zoomOnDoubleClick && !store.zoomOnPinch) return false
+
+  // during a selection we prevent all other interactions
+  if (selectionKeyPressed.value) return false
+
+  // if zoom on double click is disabled, we prevent the double click event
+  if (!store.zoomOnDoubleClick && event.type === 'dblclick') return false
+
+  // if the target element is inside an element with the nowheel class, we prevent zooming
+  if (isWrappedWithClass(event, store.noWheelClassName) && event.type === 'wheel') return false
+
+  // if the target element is inside an element with the nopan class, we prevent panning
+  if (isWrappedWithClass(event, store.noPanClassName) && event.type !== 'wheel') return false
+
+  if (!store.zoomOnPinch && event.ctrlKey && event.type === 'wheel') return false
+
+  // when there is no scroll handling enabled, we prevent all wheel events
+  if (!zoomScroll && !store.panOnScroll && !pinchZoom && event.type === 'wheel') return false
+
+  // if the pane is not movable, we prevent dragging it with mousestart or touchstart
+  if (!store.panOnDrag && (event.type === 'mousedown' || event.type === 'touchstart')) return false
+
+  // default filter for d3-zoom
+  return (!event.ctrlKey || event.type === 'wheel') && !event.button
+})
+</script>
+<script lang="ts">
+export default {
+  name: 'Zoom',
+}
+</script>
+<template>
+  <slot />
+</template>

package/src/container/VueFlow/VueFlow.vue

@@ -1,5 +1,5 @@
 <script lang="ts" setup>
-import ZoomPane from '../ZoomPane/ZoomPane.vue'
+import Viewport from '../Viewport/Viewport.vue'
 import { createHooks, useHooks } from '../../store'
 import { useVueFlow } from '../../composables'
 import type { FlowProps } from '../../types/flow'
@@ -91,7 +91,7 @@ export default {
 </script>
 <template>
   <div class="vue-flow">
-    <ZoomPane :key="`renderer-${id}`">
+    <Viewport :key="`renderer-${id}`">
       <template #nodes>
         <template v-for="nodeName of Object.keys(getNodeTypes)" :key="`node-${nodeName}-${id}`">
           <slot :name="`node-${nodeName}`" />
@@ -106,7 +106,7 @@ export default {
         <slot name="connection-line" />
       </template>
       <slot name="zoom-pane" />
-    </ZoomPane>
+    </Viewport>
     <slot />
   </div>
 </template>