[feat] new LiveCollaborators behind feature flag (#1219)

In this PR I'm adding new versions of the `LiveCollaborators` and
`Collaborators` components for the ephemeral state work. They are behind
a feature flag for now.

apps/examples/package.json

@@ -44,7 +44,7 @@
 	"dependencies": {
 		"@tldraw/tldraw": "workspace:*",
 		"react-router-dom": "^6.9.0",
-		"signia": "0.1.1",
-		"signia-react": "0.1.1"
+		"signia": "0.1.4",
+		"signia-react": "0.1.4"
 	}
 }

packages/editor/api-report.md

@@ -2650,9 +2650,15 @@ export const useApp: () => App;
 // @public (undocumented)
 export function useContainer(): HTMLDivElement;
 
+// @internal (undocumented)
+export function usePeerIds(): TLUserId[];
+
 // @public (undocumented)
 export function usePrefersReducedMotion(): boolean;
 
+// @internal (undocumented)
+export function usePresence(userId: TLUserId): null | TLInstancePresence;
+
 // @public (undocumented)
 export function useQuickReactor(name: string, reactFn: () => void, deps?: any[]): void;
 

packages/editor/src/index.ts

@@ -171,6 +171,8 @@ export { normalizeWheel } from './lib/hooks/shared'
 export { useApp } from './lib/hooks/useApp'
 export { useContainer } from './lib/hooks/useContainer'
 export type { TLEditorComponents } from './lib/hooks/useEditorComponents'
+export { usePeerIds } from './lib/hooks/usePeerIds'
+export { usePresence } from './lib/hooks/usePresence'
 export { useQuickReactor } from './lib/hooks/useQuickReactor'
 export { useReactor } from './lib/hooks/useReactor'
 export { useUrlState } from './lib/hooks/useUrlState'

packages/editor/src/lib/components/Canvas.tsx

@@ -17,6 +17,7 @@ import { useQuickReactor } from '../hooks/useQuickReactor'
 import { useScreenBounds } from '../hooks/useScreenBounds'
 import { debugFlags } from '../utils/debug-flags'
 import { LiveCollaborators } from './LiveCollaborators'
+import { LiveCollaboratorsNext } from './LiveCollaboratorsNext'
 import { SelectionBg } from './SelectionBg'
 import { SelectionFg } from './SelectionFg'
 import { Shape } from './Shape'
@@ -134,7 +135,11 @@ export const Canvas = track(function Canvas({
 					<HintedShapeIndicator />
 					<SnapLinesWrapper />
 					<HandlesWrapper />
+					{process.env.NEXT_PUBLIC_TLDRAW_NEW_COLLABORATORS ? (
+						<LiveCollaboratorsNext />
+					) : (
 						<LiveCollaborators />
+					)}
 				</g>
 			</svg>
 		</div>

packages/editor/src/lib/components/LiveCollaboratorsNext.tsx

@@ -0,0 +1,84 @@
+import { TLUserId } from '@tldraw/tlschema'
+import { track } from 'signia-react'
+import { useApp } from '../hooks/useApp'
+import { useEditorComponents } from '../hooks/useEditorComponents'
+import { usePeerIds } from '../hooks/usePeerIds'
+import { usePresence } from '../hooks/usePresence'
+
+export const LiveCollaboratorsNext = track(function Collaborators() {
+	const peerIds = usePeerIds()
+	return (
+		<g>
+			{peerIds.map((id) => (
+				<Collaborator key={id} userId={id} />
+			))}
+		</g>
+	)
+})
+
+const Collaborator = track(function Collaborator({ userId }: { userId: TLUserId }) {
+	const app = useApp()
+	const { viewportPageBounds, zoomLevel } = app
+
+	const {
+		CollaboratorBrush,
+		CollaboratorScribble,
+		CollaboratorCursor,
+		CollaboratorHint,
+		CollaboratorShapeIndicator,
+	} = useEditorComponents()
+
+	const latestPresence = usePresence(userId)
+	if (!latestPresence) return null
+
+	// if the collaborator is on another page, ignore them
+	if (latestPresence.currentPageId !== app.currentPageId) return null
+
+	const { brush, scribble, selectedIds, userName, cursor, color } = latestPresence
+
+	// Add a little padding to the top-left of the viewport
+	// so that the cursor doesn't get cut off
+	const isCursorInViewport = !(
+		cursor.x < viewportPageBounds.minX - 12 / zoomLevel ||
+		cursor.y < viewportPageBounds.minY - 16 / zoomLevel ||
+		cursor.x > viewportPageBounds.maxX - 12 / zoomLevel ||
+		cursor.y > viewportPageBounds.maxY - 16 / zoomLevel
+	)
+
+	return (
+		<>
+			{brush && CollaboratorBrush ? (
+				<CollaboratorBrush key={userId + '_brush'} brush={brush} color={color} />
+			) : null}
+			{isCursorInViewport && CollaboratorCursor ? (
+				<CollaboratorCursor
+					key={userId + '_cursor'}
+					point={cursor}
+					color={color}
+					zoom={zoomLevel}
+					nameTag={userName !== 'New User' ? userName : null}
+				/>
+			) : CollaboratorHint ? (
+				<CollaboratorHint
+					key={userId + '_cursor_hint'}
+					point={cursor}
+					color={color}
+					zoom={zoomLevel}
+					viewport={viewportPageBounds}
+				/>
+			) : null}
+			{scribble && CollaboratorScribble ? (
+				<CollaboratorScribble
+					key={userId + '_scribble'}
+					scribble={scribble}
+					color={color}
+					zoom={zoomLevel}
+				/>
+			) : null}
+			{CollaboratorShapeIndicator &&
+				selectedIds.map((shapeId) => (
+					<CollaboratorShapeIndicator key={userId + '_' + shapeId} id={shapeId} color={color} />
+				))}
+		</>
+	)
+})

packages/editor/src/lib/hooks/usePeerIds.ts

@@ -0,0 +1,25 @@
+import uniq from 'lodash.uniq'
+import { useMemo } from 'react'
+import { useComputed, useValue } from 'signia-react'
+import { useApp } from './useApp'
+
+// TODO: maybe move this to a computed property on the App class?
+/**
+ * @returns The list of peer UserIDs
+ * @internal
+ */
+export function usePeerIds() {
+	const app = useApp()
+	const $presences = useMemo(() => {
+		return app.store.query.records('instance_presence')
+	}, [app])
+
+	const $userIds = useComputed(
+		'userIds',
+		() => uniq($presences.value.map((p) => p.userId)).sort(),
+		{ isEqual: (a, b) => a.join(',') === b.join?.(',') },
+		[$presences]
+	)
+
+	return useValue($userIds)
+}

packages/editor/src/lib/hooks/usePresence.ts

@@ -0,0 +1,31 @@
+import { TLInstancePresence, TLUserId } from '@tldraw/tlschema'
+import { useMemo } from 'react'
+import { useValue } from 'signia-react'
+import { useApp } from './useApp'
+
+// TODO: maybe move this to a computed property on the App class?
+/**
+ * @returns The list of peer UserIDs
+ * @internal
+ */
+export function usePresence(userId: TLUserId): TLInstancePresence | null {
+	const app = useApp()
+
+	const $presences = useMemo(() => {
+		return app.store.query.records('instance_presence', () => ({
+			userId: { eq: userId },
+		}))
+	}, [app, userId])
+
+	const latestPresence = useValue(
+		`latestPresence:${userId}`,
+		() => {
+			return $presences.value
+				.slice()
+				.sort((a, b) => b.lastActivityTimestamp - a.lastActivityTimestamp)[0]
+		},
+		[]
+	)
+
+	return latestPresence ?? null
+}

public-yarn.lock

@@ -9483,8 +9483,8 @@ __metadata:
     react: ^18.2.0
     react-dom: ^18.2.0
     react-router-dom: ^6.9.0
-    signia: 0.1.1
-    signia-react: 0.1.1
+    signia: 0.1.4
+    signia-react: 0.1.4
   languageName: unknown
   linkType: soft
 
@@ -16724,21 +16724,21 @@ __metadata:
   languageName: node
   linkType: hard
 
-"signia-react@npm:0.1.1":
-  version: 0.1.1
-  resolution: "signia-react@npm:0.1.1"
+"signia-react@npm:0.1.4":
+  version: 0.1.4
+  resolution: "signia-react@npm:0.1.4"
   dependencies:
-    signia: 0.1.1
+    signia: 0.1.4
   peerDependencies:
     react: ^18
-  checksum: 134e32dad5f9b4e54f13d00e8ea0ed56d3b80a4fa9dcd469071906ee2501fec7f0dde8097f1c410be27c8dabf0bf81d3d73d76d579da22b3904a14d5005e872a
+  checksum: 7e443c9b94e60cd1eeb3726d048d66ab4ff6b26c14b4ca0fc9542ce2cd5997071b1d7a870481e5d88e7d0442332d65a14239a831b1f987463f4a9ca196d7de45
   languageName: node
   linkType: hard
 
-"signia@npm:0.1.1":
-  version: 0.1.1
-  resolution: "signia@npm:0.1.1"
-  checksum: 0fc961c533266604241543d079edd8a8d28264ec769d28c660a61d88d0c1da4ddbab8a04f89b5ff2c30474adfc36da98db8a22c881364de127d53c8315613b61
+"signia@npm:0.1.4":
+  version: 0.1.4
+  resolution: "signia@npm:0.1.4"
+  checksum: 0daab872c3e335c74a464a3b592cfa0fc5e1e0b65e61eecdf4e0476830791543add8a661b9b33ce9e0f6c3f0f8093ef1965955a64ec510cfcaaf15066bd25e94
   languageName: node
   linkType: hard