canvas-website/src/hooks/usePinnedToView.ts

339 lines
12 KiB
TypeScript

import { useEffect, useRef } from 'react'
import { Editor, TLShapeId, getIndexAbove } from 'tldraw'
export interface PinnedViewOptions {
/**
* The position to pin the shape at.
* - 'current': Keep at current screen position (default)
* - 'top-center': Pin to top center of viewport
* - 'bottom-center': Pin to bottom center of viewport
* - 'center': Pin to center of viewport
*/
position?: 'current' | 'top-center' | 'bottom-center' | 'center'
/**
* Offset from the edge (for top-center, bottom-center positions)
*/
offsetY?: number
offsetX?: number
}
/**
* Hook to manage shapes pinned to the viewport.
* When a shape is pinned, it stays in the same screen position as the camera
* moves and zooms. The shape scales normally with zoom.
*
* Uses store.listen for immediate synchronous updates when the camera changes,
* ensuring zero visual lag between camera movement and shape repositioning.
*/
export function usePinnedToView(
editor: Editor | null,
shapeId: string | undefined,
isPinned: boolean,
options: PinnedViewOptions = {}
) {
const { position = 'current', offsetY = 0, offsetX = 0 } = options
const pinnedScreenPositionRef = useRef<{ x: number; y: number } | null>(null)
const originalCoordinatesRef = useRef<{ x: number; y: number } | null>(null)
const wasPinnedRef = useRef<boolean>(false)
const isUpdatingRef = useRef<boolean>(false)
const driftAnimationRef = useRef<number | null>(null)
useEffect(() => {
if (!editor || !shapeId) {
return
}
const shape = editor.getShape(shapeId as TLShapeId)
if (!shape) return
// Helper to clear all pin-related state
const clearPinState = () => {
pinnedScreenPositionRef.current = null
originalCoordinatesRef.current = null
isUpdatingRef.current = false
if (driftAnimationRef.current) {
cancelAnimationFrame(driftAnimationRef.current)
driftAnimationRef.current = null
}
}
// Helper to clean shape meta of any pin-related properties
const cleanShapeMeta = (currentShape: any) => {
const meta = currentShape.meta || {}
// Remove all pin-related meta properties
const { originalX, originalY, pinnedAtZoom, ...cleanMeta } = meta as any
// Only update if there were pin properties to remove
if ('originalX' in meta || 'originalY' in meta || 'pinnedAtZoom' in meta) {
try {
editor.updateShape({
id: shapeId as TLShapeId,
type: currentShape.type,
meta: cleanMeta,
})
} catch (e) {
// Ignore errors during cleanup
}
}
return cleanMeta
}
// If just became pinned (transition from false to true)
if (isPinned && !wasPinnedRef.current) {
// Clear any leftover state from previous pin sessions
clearPinState()
// Store the original coordinates - these will be restored when unpinned
originalCoordinatesRef.current = { x: shape.x, y: shape.y }
// Store original position in meta for unpinning (clean any old meta first)
const cleanMeta = cleanShapeMeta(shape)
editor.updateShape({
id: shapeId as TLShapeId,
type: shape.type,
meta: {
...cleanMeta,
originalX: shape.x,
originalY: shape.y,
},
})
// Calculate screen position based on position option
let screenPoint: { x: number; y: number }
const viewport = editor.getViewportScreenBounds()
const currentCamera = editor.getCamera()
const shapeWidth = (shape.props as any).w || 0
const shapeHeight = (shape.props as any).h || 0
if (position === 'top-center') {
screenPoint = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + offsetY,
}
} else if (position === 'bottom-center') {
screenPoint = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + viewport.h - (shapeHeight * currentCamera.z) - offsetY,
}
} else if (position === 'center') {
screenPoint = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + (viewport.h / 2) - (shapeHeight * currentCamera.z / 2) + offsetY,
}
} else {
// Default: use current position - shape stays exactly where it is
const pagePoint = { x: shape.x, y: shape.y }
screenPoint = editor.pageToScreen(pagePoint)
}
pinnedScreenPositionRef.current = { x: screenPoint.x, y: screenPoint.y }
// Bring the shape to the front
try {
const allShapes = editor.getCurrentPageShapes()
let highestIndex = shape.index
for (const s of allShapes) {
if (s.id !== shape.id && s.index > highestIndex) {
highestIndex = s.index
}
}
if (highestIndex > shape.index) {
const newIndex = getIndexAbove(highestIndex)
editor.updateShape({
id: shapeId as TLShapeId,
type: shape.type,
index: newIndex,
})
}
} catch (error) {
console.error('Error bringing pinned shape to front:', error)
}
}
// If just became unpinned, animate back to original coordinates
if (!isPinned && wasPinnedRef.current) {
// Cancel any ongoing animations
if (driftAnimationRef.current) {
cancelAnimationFrame(driftAnimationRef.current)
driftAnimationRef.current = null
}
// Get original coordinates from meta
const currentShape = editor.getShape(shapeId as TLShapeId)
if (currentShape) {
const originalX = (currentShape.meta as any)?.originalX ?? originalCoordinatesRef.current?.x ?? currentShape.x
const originalY = (currentShape.meta as any)?.originalY ?? originalCoordinatesRef.current?.y ?? currentShape.y
const startX = currentShape.x
const startY = currentShape.y
const targetX = originalX
const targetY = originalY
// Calculate distance
const distance = Math.sqrt(
Math.pow(targetX - startX, 2) + Math.pow(targetY - startY, 2)
)
// Immediately clear refs so next pin session starts fresh
pinnedScreenPositionRef.current = null
originalCoordinatesRef.current = null
if (distance > 1) {
// Animation parameters
const duration = 600 // 600ms for a calm drift
const startTime = performance.now()
const easeOutCubic = (t: number): number => 1 - Math.pow(1 - t, 3)
const animateDrift = (currentTime: number) => {
const elapsed = currentTime - startTime
const progress = Math.min(elapsed / duration, 1)
const easedProgress = easeOutCubic(progress)
const currentX = startX + (targetX - startX) * easedProgress
const currentY = startY + (targetY - startY) * easedProgress
try {
editor.updateShape({
id: shapeId as TLShapeId,
type: currentShape.type,
x: currentX,
y: currentY,
})
} catch (error) {
console.error('Error during drift animation:', error)
driftAnimationRef.current = null
return
}
if (progress < 1) {
driftAnimationRef.current = requestAnimationFrame(animateDrift)
} else {
// Animation complete - clear pinned meta data
cleanShapeMeta(currentShape)
driftAnimationRef.current = null
}
}
driftAnimationRef.current = requestAnimationFrame(animateDrift)
} else {
// Distance is too small, just set directly and clear meta
try {
editor.updateShape({
id: shapeId as TLShapeId,
type: currentShape.type,
x: targetX,
y: targetY,
})
cleanShapeMeta(currentShape)
} catch (error) {
console.error('Error restoring original coordinates:', error)
}
}
} else {
// Shape doesn't exist, just clear refs
pinnedScreenPositionRef.current = null
originalCoordinatesRef.current = null
}
}
wasPinnedRef.current = isPinned
if (!isPinned) {
return
}
// Function to update pinned position - called synchronously on camera changes
const updatePinnedPosition = () => {
if (isUpdatingRef.current || !editor || !shapeId) {
return
}
const currentShape = editor.getShape(shapeId as TLShapeId)
if (!currentShape) {
return
}
// Get the target screen position
let pinnedScreenPos: { x: number; y: number }
if (position !== 'current') {
const viewport = editor.getViewportScreenBounds()
const currentCamera = editor.getCamera()
const shapeWidth = (currentShape.props as any).w || 0
const shapeHeight = (currentShape.props as any).h || 0
if (position === 'top-center') {
pinnedScreenPos = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + offsetY,
}
} else if (position === 'bottom-center') {
pinnedScreenPos = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + viewport.h - (shapeHeight * currentCamera.z) - offsetY,
}
} else if (position === 'center') {
pinnedScreenPos = {
x: viewport.x + (viewport.w / 2) - (shapeWidth * currentCamera.z / 2) + offsetX,
y: viewport.y + (viewport.h / 2) - (shapeHeight * currentCamera.z / 2) + offsetY,
}
} else {
pinnedScreenPos = pinnedScreenPositionRef.current!
}
} else {
if (!pinnedScreenPositionRef.current) {
return
}
pinnedScreenPos = pinnedScreenPositionRef.current
}
try {
// Convert screen position back to page coordinates
const newPagePoint = editor.screenToPage(pinnedScreenPos)
// Always update - no threshold, for maximum responsiveness
isUpdatingRef.current = true
editor.updateShape({
id: shapeId as TLShapeId,
type: currentShape.type,
x: newPagePoint.x,
y: newPagePoint.y,
})
isUpdatingRef.current = false
} catch (error) {
console.error('Error updating pinned shape position:', error)
isUpdatingRef.current = false
}
}
// Use store.listen to react immediately to camera changes
// This is more immediate than 'tick' as it fires synchronously when the store changes
const unsubscribe = editor.store.listen(
(entry) => {
// Only react to camera changes
const hasCamera = Object.entries(entry.changes.updated).some(
([, [, record]]) => record.typeName === 'camera'
)
if (hasCamera && !isUpdatingRef.current) {
updatePinnedPosition()
}
},
{ source: 'all', scope: 'document' }
)
// Don't call updatePinnedPosition immediately - the shape is already at
// the correct position since we just captured its current screen position
// Only start listening for camera changes
return () => {
if (driftAnimationRef.current) {
cancelAnimationFrame(driftAnimationRef.current)
driftAnimationRef.current = null
}
unsubscribe()
}
}, [editor, shapeId, isPinned, position, offsetX, offsetY])
}