feat: partition main canvas vertically (#6759)

Co-authored-by: Marcel Mraz <marcel.mraz@adacta-fintech.com>
Co-authored-by: dwelle <luzar.david@gmail.com>

src/components/canvases/InteractiveCanvas.tsx

@@ -0,0 +1,222 @@
+import React, { useEffect, useRef } from "react";
+import { renderInteractiveScene } from "../../renderer/renderScene";
+import {
+  isRenderThrottlingEnabled,
+  isShallowEqual,
+  sceneCoordsToViewportCoords,
+} from "../../utils";
+import { CURSOR_TYPE } from "../../constants";
+import { t } from "../../i18n";
+import type { DOMAttributes } from "react";
+import type { AppState, InteractiveCanvasAppState } from "../../types";
+import type {
+  InteractiveCanvasRenderConfig,
+  RenderInteractiveSceneCallback,
+} from "../../scene/types";
+import type { NonDeletedExcalidrawElement } from "../../element/types";
+
+type InteractiveCanvasProps = {
+  canvas: HTMLCanvasElement | null;
+  elements: readonly NonDeletedExcalidrawElement[];
+  visibleElements: readonly NonDeletedExcalidrawElement[];
+  selectedElements: readonly NonDeletedExcalidrawElement[];
+  versionNonce: number | undefined;
+  selectionNonce: number | undefined;
+  scale: number;
+  appState: InteractiveCanvasAppState;
+  renderInteractiveSceneCallback: (
+    data: RenderInteractiveSceneCallback,
+  ) => void;
+  handleCanvasRef: (canvas: HTMLCanvasElement | null) => void;
+  onContextMenu: Exclude<
+    DOMAttributes<HTMLCanvasElement | HTMLDivElement>["onContextMenu"],
+    undefined
+  >;
+  onPointerMove: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onPointerMove"],
+    undefined
+  >;
+  onPointerUp: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onPointerUp"],
+    undefined
+  >;
+  onPointerCancel: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onPointerCancel"],
+    undefined
+  >;
+  onTouchMove: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onTouchMove"],
+    undefined
+  >;
+  onPointerDown: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onPointerDown"],
+    undefined
+  >;
+  onDoubleClick: Exclude<
+    DOMAttributes<HTMLCanvasElement>["onDoubleClick"],
+    undefined
+  >;
+};
+
+const InteractiveCanvas = (props: InteractiveCanvasProps) => {
+  const isComponentMounted = useRef(false);
+
+  useEffect(() => {
+    if (!isComponentMounted.current) {
+      isComponentMounted.current = true;
+      return;
+    }
+
+    const cursorButton: {
+      [id: string]: string | undefined;
+    } = {};
+    const pointerViewportCoords: InteractiveCanvasRenderConfig["remotePointerViewportCoords"] =
+      {};
+    const remoteSelectedElementIds: InteractiveCanvasRenderConfig["remoteSelectedElementIds"] =
+      {};
+    const pointerUsernames: { [id: string]: string } = {};
+    const pointerUserStates: { [id: string]: string } = {};
+
+    props.appState.collaborators.forEach((user, socketId) => {
+      if (user.selectedElementIds) {
+        for (const id of Object.keys(user.selectedElementIds)) {
+          if (!(id in remoteSelectedElementIds)) {
+            remoteSelectedElementIds[id] = [];
+          }
+          remoteSelectedElementIds[id].push(socketId);
+        }
+      }
+      if (!user.pointer) {
+        return;
+      }
+      if (user.username) {
+        pointerUsernames[socketId] = user.username;
+      }
+      if (user.userState) {
+        pointerUserStates[socketId] = user.userState;
+      }
+      pointerViewportCoords[socketId] = sceneCoordsToViewportCoords(
+        {
+          sceneX: user.pointer.x,
+          sceneY: user.pointer.y,
+        },
+        props.appState,
+      );
+      cursorButton[socketId] = user.button;
+    });
+
+    const selectionColor = getComputedStyle(
+      document.querySelector(".excalidraw")!,
+    ).getPropertyValue("--color-selection");
+
+    renderInteractiveScene(
+      {
+        canvas: props.canvas,
+        elements: props.elements,
+        visibleElements: props.visibleElements,
+        selectedElements: props.selectedElements,
+        scale: window.devicePixelRatio,
+        appState: props.appState,
+        renderConfig: {
+          remotePointerViewportCoords: pointerViewportCoords,
+          remotePointerButton: cursorButton,
+          remoteSelectedElementIds,
+          remotePointerUsernames: pointerUsernames,
+          remotePointerUserStates: pointerUserStates,
+          selectionColor,
+          renderScrollbars: false,
+        },
+        callback: props.renderInteractiveSceneCallback,
+      },
+      isRenderThrottlingEnabled(),
+    );
+  });
+
+  return (
+    <canvas
+      className="excalidraw__canvas interactive"
+      style={{
+        width: props.appState.width,
+        height: props.appState.height,
+        cursor: props.appState.viewModeEnabled
+          ? CURSOR_TYPE.GRAB
+          : CURSOR_TYPE.AUTO,
+      }}
+      width={props.appState.width * props.scale}
+      height={props.appState.height * props.scale}
+      ref={props.handleCanvasRef}
+      onContextMenu={props.onContextMenu}
+      onPointerMove={props.onPointerMove}
+      onPointerUp={props.onPointerUp}
+      onPointerCancel={props.onPointerCancel}
+      onTouchMove={props.onTouchMove}
+      onPointerDown={props.onPointerDown}
+      onDoubleClick={
+        props.appState.viewModeEnabled ? undefined : props.onDoubleClick
+      }
+    >
+      {t("labels.drawingCanvas")}
+    </canvas>
+  );
+};
+
+const getRelevantAppStateProps = (
+  appState: AppState,
+): Omit<InteractiveCanvasAppState, "editingElement"> => ({
+  zoom: appState.zoom,
+  scrollX: appState.scrollX,
+  scrollY: appState.scrollY,
+  width: appState.width,
+  height: appState.height,
+  viewModeEnabled: appState.viewModeEnabled,
+  editingGroupId: appState.editingGroupId,
+  editingLinearElement: appState.editingLinearElement,
+  selectedElementIds: appState.selectedElementIds,
+  frameToHighlight: appState.frameToHighlight,
+  offsetLeft: appState.offsetLeft,
+  offsetTop: appState.offsetTop,
+  theme: appState.theme,
+  pendingImageElementId: appState.pendingImageElementId,
+  selectionElement: appState.selectionElement,
+  selectedGroupIds: appState.selectedGroupIds,
+  selectedLinearElement: appState.selectedLinearElement,
+  multiElement: appState.multiElement,
+  isBindingEnabled: appState.isBindingEnabled,
+  suggestedBindings: appState.suggestedBindings,
+  isRotating: appState.isRotating,
+  elementsToHighlight: appState.elementsToHighlight,
+  openSidebar: appState.openSidebar,
+  showHyperlinkPopup: appState.showHyperlinkPopup,
+  collaborators: appState.collaborators, // Necessary for collab. sessions
+  activeEmbeddable: appState.activeEmbeddable,
+});
+
+const areEqual = (
+  prevProps: InteractiveCanvasProps,
+  nextProps: InteractiveCanvasProps,
+) => {
+  // This could be further optimised if needed, as we don't have to render interactive canvas on each scene mutation
+  if (
+    prevProps.selectionNonce !== nextProps.selectionNonce ||
+    prevProps.versionNonce !== nextProps.versionNonce ||
+    prevProps.scale !== nextProps.scale ||
+    // we need to memoize on element arrays because they may have renewed
+    // even if versionNonce didn't change (e.g. we filter elements out based
+    // on appState)
+    prevProps.elements !== nextProps.elements ||
+    prevProps.visibleElements !== nextProps.visibleElements ||
+    prevProps.selectedElements !== nextProps.selectedElements
+  ) {
+    return false;
+  }
+
+  // Comparing the interactive appState for changes in case of some edge cases
+  return isShallowEqual(
+    // asserting AppState because we're being passed the whole AppState
+    // but resolve to only the InteractiveCanvas-relevant props
+    getRelevantAppStateProps(prevProps.appState as AppState),
+    getRelevantAppStateProps(nextProps.appState as AppState),
+  );
+};
+
+export default React.memo(InteractiveCanvas, areEqual);