Optimised re-renders with sortable tiles

src/components/map/MapTiles.js

@@ -4,6 +4,7 @@ import MapTile from "./MapTile";
 import MapTileGroup from "./MapTileGroup";
 
 import SortableTiles from "../tile/SortableTiles";
+import SortableTilesDragOverlay from "../tile/SortableTilesDragOverlay";
 
 import { getGroupItems } from "../../helpers/group";
 
@@ -57,7 +58,12 @@ function MapTiles({ mapsById, onMapEdit, onMapSelect, subgroup }) {
     }
   }
 
-  return <SortableTiles renderTile={renderTile} subgroup={subgroup} />;
+  return (
+    <>
+      <SortableTiles renderTile={renderTile} subgroup={subgroup} />
+      <SortableTilesDragOverlay renderTile={renderTile} subgroup={subgroup} />
+    </>
+  );
 }
 
 export default MapTiles;

src/components/tile/SortableTiles.js

@@ -1,26 +1,24 @@
 import React from "react";
-import { createPortal } from "react-dom";
-import { DragOverlay } from "@dnd-kit/core";
 import { SortableContext } from "@dnd-kit/sortable";
-import { animated, useSpring, config } from "react-spring";
-import { Badge } from "theme-ui";
 
 import { moveGroupsInto } from "../../helpers/group";
 import { keyBy } from "../../helpers/shared";
-import Vector2 from "../../helpers/Vector2";
 
 import SortableTile from "./SortableTile";
 
 import {
-  useTileDrag,
+  useTileDragId,
+  useTileDragCursor,
+  useTileOverGroupId,
   BASE_SORTABLE_ID,
   GROUP_SORTABLE_ID,
-  GROUP_ID_PREFIX,
 } from "../../contexts/TileDragContext";
 import { useGroup } from "../../contexts/GroupContext";
 
 function SortableTiles({ renderTile, subgroup }) {
-  const { dragId, overId, dragCursor } = useTileDrag();
+  const dragId = useTileDragId();
+  const dragCursor = useTileDragCursor();
+  const overGroupId = useTileOverGroupId();
   const {
     groups,
     selectedGroupIds: allSelectedIds,
@@ -46,15 +44,6 @@ function SortableTiles({ renderTile, subgroup }) {
   const disableSorting = (openGroupId && !subgroup) || filter;
   const disableGrouping = subgroup || disableSorting || filter;
 
-  const dragBounce = useSpring({
-    transform: !!dragId ? "scale(0.9)" : "scale(1)",
-    config: config.wobbly,
-    position: "relative",
-  });
-
-  const overGroupId =
-    overId && overId.startsWith(GROUP_ID_PREFIX) && overId.slice(9);
-
   function renderSortableGroup(group, selectedGroups) {
     if (overGroupId === group.id && dragId && group.id !== dragId) {
       // If dragging over a group render a preview of that group
@@ -68,57 +57,6 @@ function SortableTiles({ renderTile, subgroup }) {
     return renderTile(group);
   }
 
-  function renderDragOverlays() {
-    let selectedIndices = selectedGroupIds.map((groupId) =>
-      activeGroups.findIndex((group) => group.id === groupId)
-    );
-    const activeIndex = activeGroups.findIndex((group) => group.id === dragId);
-    // Sort so the draging tile is the first element
-    selectedIndices = selectedIndices.sort((a, b) =>
-      a === activeIndex ? -1 : b === activeIndex ? 1 : 0
-    );
-
-    selectedIndices = selectedIndices.slice(0, 5);
-
-    let coords = selectedIndices.map(
-      (_, index) => new Vector2(5 * index, 5 * index)
-    );
-
-    // Reverse so the first element is rendered on top
-    selectedIndices = selectedIndices.reverse();
-    coords = coords.reverse();
-
-    const selectedGroups = selectedIndices.map((index) => activeGroups[index]);
-
-    return selectedGroups.map((group, index) => (
-      <DragOverlay dropAnimation={null} key={group.id}>
-        <div
-          style={{
-            transform: `translate(${coords[index].x}%, ${coords[index].y}%)`,
-            cursor: dragCursor,
-          }}
-        >
-          <animated.div style={dragBounce}>
-            {renderTile(group)}
-            {index === selectedIndices.length - 1 &&
-              selectedGroupIds.length > 1 && (
-                <Badge
-                  sx={{
-                    position: "absolute",
-                    top: 0,
-                    right: 0,
-                    transform: "translate(25%, -25%)",
-                  }}
-                >
-                  {selectedGroupIds.length}
-                </Badge>
-              )}
-          </animated.div>
-        </div>
-      </DragOverlay>
-    ));
-  }
-
   function renderTiles() {
     const groupsByIds = keyBy(activeGroups, "id");
     const selectedGroupIdsSet = new Set(selectedGroupIds);
@@ -156,7 +94,6 @@ function SortableTiles({ renderTile, subgroup }) {
   return (
     <SortableContext items={activeGroups} id={sortableId}>
       {renderTiles()}
-      {createPortal(dragId && renderDragOverlays(), document.body)}
     </SortableContext>
   );
 }

src/components/tile/SortableTilesDragOverlay.js

@@ -0,0 +1,93 @@
+import React from "react";
+import { createPortal } from "react-dom";
+import { DragOverlay } from "@dnd-kit/core";
+import { animated, useSpring, config } from "react-spring";
+import { Badge } from "theme-ui";
+
+import Vector2 from "../../helpers/Vector2";
+
+import { useTileDragId } from "../../contexts/TileDragContext";
+import { useGroup } from "../../contexts/GroupContext";
+
+function SortableTilesDragOverlay({ renderTile, subgroup }) {
+  const dragId = useTileDragId();
+  const {
+    groups,
+    selectedGroupIds: allSelectedIds,
+    filter,
+    openGroupId,
+    openGroupItems,
+    filteredGroupItems,
+  } = useGroup();
+
+  const activeGroups = subgroup
+    ? openGroupItems
+    : filter
+    ? filteredGroupItems
+    : groups;
+
+  // Only populate selected groups if needed
+  let selectedGroupIds = [];
+  if ((subgroup && openGroupId) || (!subgroup && !openGroupId)) {
+    selectedGroupIds = allSelectedIds;
+  }
+  const dragBounce = useSpring({
+    transform: !!dragId ? "scale(0.9)" : "scale(1)",
+    config: config.wobbly,
+    position: "relative",
+  });
+
+  function renderDragOverlays() {
+    let selectedIndices = selectedGroupIds.map((groupId) =>
+      activeGroups.findIndex((group) => group.id === groupId)
+    );
+    const activeIndex = activeGroups.findIndex((group) => group.id === dragId);
+    // Sort so the draging tile is the first element
+    selectedIndices = selectedIndices.sort((a, b) =>
+      a === activeIndex ? -1 : b === activeIndex ? 1 : 0
+    );
+
+    selectedIndices = selectedIndices.slice(0, 5);
+
+    let coords = selectedIndices.map(
+      (_, index) => new Vector2(5 * index, 5 * index)
+    );
+
+    // Reverse so the first element is rendered on top
+    selectedIndices = selectedIndices.reverse();
+    coords = coords.reverse();
+
+    const selectedGroups = selectedIndices.map((index) => activeGroups[index]);
+
+    return selectedGroups.map((group, index) => (
+      <DragOverlay dropAnimation={null} key={group.id}>
+        <div
+          style={{
+            transform: `translate(${coords[index].x}%, ${coords[index].y}%)`,
+          }}
+        >
+          <animated.div style={dragBounce}>
+            {renderTile(group)}
+            {index === selectedIndices.length - 1 &&
+              selectedGroupIds.length > 1 && (
+                <Badge
+                  sx={{
+                    position: "absolute",
+                    top: 0,
+                    right: 0,
+                    transform: "translate(25%, -25%)",
+                  }}
+                >
+                  {selectedGroupIds.length}
+                </Badge>
+              )}
+          </animated.div>
+        </div>
+      </DragOverlay>
+    ));
+  }
+
+  return createPortal(dragId && renderDragOverlays(), document.body);
+}
+
+export default SortableTilesDragOverlay;

src/components/tile/Tile.js

@@ -16,17 +16,14 @@ function Tile({
   children,
 }) {
   const [ref, inView] = useInView({ triggerOnce: true });
-
   return (
-    <Flex
+    <Box
       sx={{
         position: "relative",
         width: "100%",
         height: "0",
         paddingTop: "100%",
         borderRadius: "4px",
-        justifyContent: "center",
-        alignItems: "center",
         overflow: "hidden",
         userSelect: "none",
       }}
@@ -128,7 +125,7 @@ function Tile({
           )}
         </>
       )}
-    </Flex>
+    </Box>
   );
 }
 

src/components/token/TokenTiles.js

@@ -5,6 +5,7 @@ import TokenTileGroup from "./TokenTileGroup";
 import TokenHiddenBadge from "./TokenHiddenBadge";
 
 import SortableTiles from "../tile/SortableTiles";
+import SortableTilesDragOverlay from "../tile/SortableTilesDragOverlay";
 
 import { getGroupItems } from "../../helpers/group";
 
@@ -61,7 +62,12 @@ function TokenTiles({ tokensById, onTokenEdit, subgroup }) {
     }
   }
 
-  return <SortableTiles renderTile={renderTile} subgroup={subgroup} />;
+  return (
+    <>
+      <SortableTiles renderTile={renderTile} subgroup={subgroup} />
+      <SortableTilesDragOverlay renderTile={renderTile} subgroup={subgroup} />
+    </>
+  );
 }
 
 export default TokenTiles;

src/contexts/TileDragContext.js

@@ -1,4 +1,4 @@
-import React, { useState, useContext } from "react";
+import React, { useState, useContext, useEffect } from "react";
 import {
   MouseSensor,
   TouchSensor,
@@ -16,7 +16,9 @@ import { moveGroupsInto, moveGroups, ungroup } from "../helpers/group";
 
 import usePreventSelect from "../hooks/usePreventSelect";
 
-const TileDragContext = React.createContext();
+const TileDragIdContext = React.createContext();
+const TileOverGroupIdContext = React.createContext();
+const TileDragCursorContext = React.createContext();
 
 export const BASE_SORTABLE_ID = "__base__";
 export const GROUP_SORTABLE_ID = "__group__";
@@ -61,7 +63,7 @@ export function TileDragProvider({
   } = useGroup();
 
   const mouseSensor = useSensor(MouseSensor, {
-    activationConstraint: { distance: 5 },
+    activationConstraint: { distance: 3 },
   });
   const touchSensor = useSensor(TouchSensor, {
     activationConstraint: { delay: 250, tolerance: 5 },
@@ -70,16 +72,23 @@ export function TileDragProvider({
 
   const sensors = useSensors(mouseSensor, touchSensor, keyboardSensor);
 
-  const [dragId, setDragId] = useState();
-  const [overId, setOverId] = useState();
+  const [dragId, setDragId] = useState(null);
+  const [overId, setOverId] = useState(null);
   const [dragCursor, setDragCursor] = useState("pointer");
 
   const [preventSelect, resumeSelect] = usePreventSelect();
 
+  const [overGroupId, setOverGroupId] = useState(null);
+  useEffect(() => {
+    setOverGroupId(
+      (overId && overId.startsWith(GROUP_ID_PREFIX) && overId.slice(9)) || null
+    );
+  }, [overId]);
+
   function handleDragStart(event) {
     const { active, over } = event;
     setDragId(active.id);
-    setOverId(over?.id);
+    setOverId(over?.id || null);
     if (!selectedGroupIds.includes(active.id)) {
       onGroupSelect(active.id);
     }
@@ -93,7 +102,7 @@ export function TileDragProvider({
   function handleDragOver(event) {
     const { over } = event;
 
-    setOverId(over?.id);
+    setOverId(over?.id || null);
     if (over) {
       if (
         over.id.startsWith(UNGROUP_ID) ||
@@ -111,8 +120,8 @@ export function TileDragProvider({
   function handleDragEnd(event) {
     const { active, over, overlayNodeClientRect } = event;
 
-    setDragId();
-    setOverId();
+    setDragId(null);
+    setOverId(null);
     setDragCursor("pointer");
     if (active && over && active.id !== over.id) {
       let selectedIndices = selectedGroupIds.map((groupId) =>
@@ -165,8 +174,8 @@ export function TileDragProvider({
   }
 
   function handleDragCancel(event) {
-    setDragId();
-    setOverId();
+    setDragId(null);
+    setOverId(null);
     setDragCursor("pointer");
 
     resumeSelect();
@@ -210,8 +219,6 @@ export function TileDragProvider({
     return closestCenter(otherRects, rect);
   }
 
-  const value = { dragId, overId, dragCursor };
-
   return (
     <DragContext
       onDragStart={handleDragStart}
@@ -221,19 +228,37 @@ export function TileDragProvider({
       sensors={sensors}
       collisionDetection={customCollisionDetection}
     >
-      <TileDragContext.Provider value={value}>
-        {children}
-      </TileDragContext.Provider>
+      <TileDragIdContext.Provider value={dragId}>
+        <TileOverGroupIdContext.Provider value={overGroupId}>
+          <TileDragCursorContext.Provider value={dragCursor}>
+            {children}
+          </TileDragCursorContext.Provider>
+        </TileOverGroupIdContext.Provider>
+      </TileDragIdContext.Provider>
     </DragContext>
   );
 }
 
-export function useTileDrag() {
-  const context = useContext(TileDragContext);
+export function useTileDragId() {
+  const context = useContext(TileDragIdContext);
   if (context === undefined) {
     throw new Error("useTileDrag must be used within a TileDragProvider");
   }
   return context;
 }
 
-export default TileDragContext;
+export function useTileOverGroupId() {
+  const context = useContext(TileOverGroupIdContext);
+  if (context === undefined) {
+    throw new Error("useTileDrag must be used within a TileDragProvider");
+  }
+  return context;
+}
+
+export function useTileDragCursor() {
+  const context = useContext(TileDragCursorContext);
+  if (context === undefined) {
+    throw new Error("useTileDrag must be used within a TileDragProvider");
+  }
+  return context;
+}