Move the pinch stuff in its own file in order to use for editors

src/display/touch_manager.js

@@ -0,0 +1,192 @@
+/* Copyright 2024 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { shadow } from "../shared/util.js";
+
+class TouchManager {
+  #container;
+
+  #isPinching = false;
+
+  #isPinchingStopped = null;
+
+  #isPinchingDisabled;
+
+  #onPinching;
+
+  #onPinchEnd;
+
+  #signal;
+
+  #touchInfo = null;
+
+  #touchManagerAC;
+
+  #touchMoveAC = null;
+
+  constructor({
+    container,
+    isPinchingDisabled = null,
+    isPinchingStopped = null,
+    onPinching = null,
+    onPinchEnd = null,
+    signal,
+  }) {
+    this.#container = container;
+    this.#isPinchingStopped = isPinchingStopped;
+    this.#isPinchingDisabled = isPinchingDisabled;
+    this.#onPinching = onPinching;
+    this.#onPinchEnd = onPinchEnd;
+    this.#touchManagerAC = new AbortController();
+    this.#signal = AbortSignal.any([signal, this.#touchManagerAC.signal]);
+
+    container.addEventListener("touchstart", this.#onTouchStart.bind(this), {
+      passive: false,
+      signal: this.#signal,
+    });
+  }
+
+  get MIN_TOUCH_DISTANCE_TO_PINCH() {
+    // The 35 is coming from:
+    //  https://searchfox.org/mozilla-central/source/gfx/layers/apz/src/GestureEventListener.cpp#36
+    //
+    // The properties TouchEvent::screenX/Y are in screen CSS pixels:
+    //  https://developer.mozilla.org/en-US/docs/Web/API/Touch/screenX#examples
+    // MIN_TOUCH_DISTANCE_TO_PINCH is in CSS pixels.
+    return shadow(
+      this,
+      "MIN_TOUCH_DISTANCE_TO_PINCH",
+      35 / (window.devicePixelRatio || 1)
+    );
+  }
+
+  #onTouchStart(evt) {
+    if (this.#isPinchingDisabled?.() || evt.touches.length < 2) {
+      return;
+    }
+
+    if (!this.#touchMoveAC) {
+      this.#touchMoveAC = new AbortController();
+      const signal = AbortSignal.any([this.#signal, this.#touchMoveAC.signal]);
+      const container = this.#container;
+      const opt = { signal, passive: false };
+      container.addEventListener(
+        "touchmove",
+        this.#onTouchMove.bind(this),
+        opt
+      );
+      container.addEventListener("touchend", this.#onTouchEnd.bind(this), opt);
+      container.addEventListener(
+        "touchcancel",
+        this.#onTouchEnd.bind(this),
+        opt
+      );
+    }
+
+    evt.preventDefault();
+
+    if (evt.touches.length !== 2 || this.#isPinchingStopped?.()) {
+      this.#touchInfo = null;
+      return;
+    }
+
+    let [touch0, touch1] = evt.touches;
+    if (touch0.identifier > touch1.identifier) {
+      [touch0, touch1] = [touch1, touch0];
+    }
+    this.#touchInfo = {
+      touch0X: touch0.screenX,
+      touch0Y: touch0.screenY,
+      touch1X: touch1.screenX,
+      touch1Y: touch1.screenY,
+    };
+  }
+
+  #onTouchMove(evt) {
+    if (!this.#touchInfo || evt.touches.length !== 2) {
+      return;
+    }
+
+    let [touch0, touch1] = evt.touches;
+    if (touch0.identifier > touch1.identifier) {
+      [touch0, touch1] = [touch1, touch0];
+    }
+    const { screenX: screen0X, screenY: screen0Y } = touch0;
+    const { screenX: screen1X, screenY: screen1Y } = touch1;
+    const touchInfo = this.#touchInfo;
+    const {
+      touch0X: pTouch0X,
+      touch0Y: pTouch0Y,
+      touch1X: pTouch1X,
+      touch1Y: pTouch1Y,
+    } = touchInfo;
+
+    const prevGapX = pTouch1X - pTouch0X;
+    const prevGapY = pTouch1Y - pTouch0Y;
+    const currGapX = screen1X - screen0X;
+    const currGapY = screen1Y - screen0Y;
+
+    const distance = Math.hypot(currGapX, currGapY) || 1;
+    const pDistance = Math.hypot(prevGapX, prevGapY) || 1;
+    if (
+      !this.#isPinching &&
+      Math.abs(pDistance - distance) <= TouchManager.MIN_TOUCH_DISTANCE_TO_PINCH
+    ) {
+      return;
+    }
+
+    touchInfo.touch0X = screen0X;
+    touchInfo.touch0Y = screen0Y;
+    touchInfo.touch1X = screen1X;
+    touchInfo.touch1Y = screen1Y;
+
+    evt.preventDefault();
+
+    if (!this.#isPinching) {
+      // Start pinching.
+      this.#isPinching = true;
+
+      // We return here else the first pinch is a bit too much
+      return;
+    }
+
+    const origin = [(screen0X + screen1X) / 2, (screen0Y + screen1Y) / 2];
+    this.#onPinching?.(origin, pDistance, distance);
+  }
+
+  #onTouchEnd(evt) {
+    this.#touchMoveAC.abort();
+    this.#touchMoveAC = null;
+
+    if (!this.#touchInfo) {
+      return;
+    }
+
+    if (this.#isPinching) {
+      this.#onPinchEnd?.();
+      this.#isPinching = false;
+    }
+
+    evt.preventDefault();
+    this.#touchInfo = null;
+  }
+
+  destroy() {
+    this.#touchManagerAC?.abort();
+    this.#touchManagerAC = null;
+  }
+}
+
+export { TouchManager };

src/pdf.js

@@ -72,6 +72,7 @@ import { DrawLayer } from "./display/draw_layer.js";
 import { GlobalWorkerOptions } from "./display/worker_options.js";
 import { HighlightOutliner } from "./display/editor/drawers/highlight.js";
 import { TextLayer } from "./display/text_layer.js";
+import { TouchManager } from "./display/touch_manager.js";
 import { XfaLayer } from "./display/xfa_layer.js";
 
 /* eslint-disable-next-line no-unused-vars */
@@ -127,6 +128,7 @@ export {
   shadow,
   stopEvent,
   TextLayer,
+  TouchManager,
   UnexpectedResponseException,
   Util,
   VerbosityLevel,

test/unit/pdf_spec.js

@@ -63,6 +63,7 @@ import { DOMSVGFactory } from "../../src/display/svg_factory.js";
 import { DrawLayer } from "../../src/display/draw_layer.js";
 import { GlobalWorkerOptions } from "../../src/display/worker_options.js";
 import { TextLayer } from "../../src/display/text_layer.js";
+import { TouchManager } from "../../src/display/touch_manager.js";
 import { XfaLayer } from "../../src/display/xfa_layer.js";
 
 const expectedAPI = Object.freeze({
@@ -105,6 +106,7 @@ const expectedAPI = Object.freeze({
   shadow,
   stopEvent,
   TextLayer,
+  TouchManager,
   UnexpectedResponseException,
   Util,
   VerbosityLevel,

web/app.js

@@ -54,6 +54,7 @@ import {
   PDFWorker,
   shadow,
   stopEvent,
+  TouchManager,
   UnexpectedResponseException,
   version,
 } from "pdfjs-lib";
@@ -94,14 +95,6 @@ import { ViewHistory } from "./view_history.js";
 
 const FORCE_PAGES_LOADED_TIMEOUT = 10000; // ms
 
-// The 35 is coming from:
-//  https://searchfox.org/mozilla-central/source/gfx/layers/apz/src/GestureEventListener.cpp#36
-//
-// The properties TouchEvent::screenX/Y are in screen CSS pixels:
-//  https://developer.mozilla.org/en-US/docs/Web/API/Touch/screenX#examples
-// MIN_TOUCH_DISTANCE_TO_PINCH is in CSS pixels.
-const MIN_TOUCH_DISTANCE_TO_PINCH = 35 / (window.devicePixelRatio || 1);
-
 const ViewOnLoad = {
   UNKNOWN: -1,
   PREVIOUS: 0, // Default value.
@@ -182,14 +175,13 @@ const PDFViewerApplication = {
   _saveInProgress: false,
   _wheelUnusedTicks: 0,
   _wheelUnusedFactor: 1,
+  _touchManager: null,
   _touchUnusedTicks: 0,
   _touchUnusedFactor: 1,
   _PDFBug: null,
   _hasAnnotationEditors: false,
   _title: document.title,
   _printAnnotationStoragePromise: null,
-  _touchInfo: null,
-  _isPinching: false,
   _isCtrlKeyDown: false,
   _caretBrowsing: null,
   _isScrolling: false,
@@ -825,6 +817,29 @@ const PDFViewerApplication = {
     this.pdfViewer.currentScaleValue = DEFAULT_SCALE_VALUE;
   },
 
+  touchPinchCallback(origin, prevDistance, distance) {
+    if (this.supportsPinchToZoom) {
+      const newScaleFactor = this._accumulateFactor(
+        this.pdfViewer.currentScale,
+        distance / prevDistance,
+        "_touchUnusedFactor"
+      );
+      this.updateZoom(null, newScaleFactor, origin);
+    } else {
+      const PIXELS_PER_LINE_SCALE = 30;
+      const ticks = this._accumulateTicks(
+        (distance - prevDistance) / PIXELS_PER_LINE_SCALE,
+        "_touchUnusedTicks"
+      );
+      this.updateZoom(ticks, null, origin);
+    }
+  },
+
+  touchPinchEndCallback() {
+    this._touchUnusedTicks = 0;
+    this._touchUnusedFactor = 1;
+  },
+
   get pagesCount() {
     return this.pdfDocument ? this.pdfDocument.numPages : 0;
   },
@@ -2029,6 +2044,15 @@ const PDFViewerApplication = {
       _windowAbortController: { signal },
     } = this;
 
+    this._touchManager = new TouchManager({
+      container: window,
+      isPinchingDisabled: () => this.pdfViewer.isInPresentationMode,
+      isPinchingStopped: () => this.overlayManager?.active,
+      onPinching: this.touchPinchCallback.bind(this),
+      onPinchEnd: this.touchPinchEndCallback.bind(this),
+      signal,
+    });
+
     function addWindowResolutionChange(evt = null) {
       if (evt) {
         pdfViewer.refresh();
@@ -2047,18 +2071,6 @@ const PDFViewerApplication = {
       passive: false,
       signal,
     });
-    window.addEventListener("touchstart", onTouchStart.bind(this), {
-      passive: false,
-      signal,
-    });
-    window.addEventListener("touchmove", onTouchMove.bind(this), {
-      passive: false,
-      signal,
-    });
-    window.addEventListener("touchend", onTouchEnd.bind(this), {
-      passive: false,
-      signal,
-    });
     window.addEventListener("click", onClick.bind(this), { signal });
     window.addEventListener("keydown", onKeyDown.bind(this), { signal });
     window.addEventListener("keyup", onKeyUp.bind(this), { signal });
@@ -2157,6 +2169,7 @@ const PDFViewerApplication = {
   unbindWindowEvents() {
     this._windowAbortController?.abort();
     this._windowAbortController = null;
+    this._touchManager = null;
   },
 
   /**
@@ -2638,107 +2651,6 @@ function onWheel(evt) {
   }
 }
 
-function onTouchStart(evt) {
-  if (this.pdfViewer.isInPresentationMode || evt.touches.length < 2) {
-    return;
-  }
-  evt.preventDefault();
-
-  if (evt.touches.length !== 2 || this.overlayManager.active) {
-    this._touchInfo = null;
-    return;
-  }
-
-  let [touch0, touch1] = evt.touches;
-  if (touch0.identifier > touch1.identifier) {
-    [touch0, touch1] = [touch1, touch0];
-  }
-  this._touchInfo = {
-    touch0X: touch0.screenX,
-    touch0Y: touch0.screenY,
-    touch1X: touch1.screenX,
-    touch1Y: touch1.screenY,
-  };
-}
-
-function onTouchMove(evt) {
-  if (!this._touchInfo || evt.touches.length !== 2) {
-    return;
-  }
-
-  const { pdfViewer, _touchInfo, supportsPinchToZoom } = this;
-  let [touch0, touch1] = evt.touches;
-  if (touch0.identifier > touch1.identifier) {
-    [touch0, touch1] = [touch1, touch0];
-  }
-  const { screenX: screen0X, screenY: screen0Y } = touch0;
-  const { screenX: screen1X, screenY: screen1Y } = touch1;
-  const {
-    touch0X: pTouch0X,
-    touch0Y: pTouch0Y,
-    touch1X: pTouch1X,
-    touch1Y: pTouch1Y,
-  } = _touchInfo;
-
-  const prevGapX = pTouch1X - pTouch0X;
-  const prevGapY = pTouch1Y - pTouch0Y;
-  const currGapX = screen1X - screen0X;
-  const currGapY = screen1Y - screen0Y;
-
-  const distance = Math.hypot(currGapX, currGapY) || 1;
-  const pDistance = Math.hypot(prevGapX, prevGapY) || 1;
-  if (
-    !this._isPinching &&
-    Math.abs(pDistance - distance) <= MIN_TOUCH_DISTANCE_TO_PINCH
-  ) {
-    return;
-  }
-
-  _touchInfo.touch0X = screen0X;
-  _touchInfo.touch0Y = screen0Y;
-  _touchInfo.touch1X = screen1X;
-  _touchInfo.touch1Y = screen1Y;
-
-  evt.preventDefault();
-
-  if (!this._isPinching) {
-    // Start pinching.
-    this._isPinching = true;
-
-    // We return here else the first pinch is a bit too much
-    return;
-  }
-
-  const origin = [(screen0X + screen1X) / 2, (screen0Y + screen1Y) / 2];
-  if (supportsPinchToZoom) {
-    const newScaleFactor = this._accumulateFactor(
-      pdfViewer.currentScale,
-      distance / pDistance,
-      "_touchUnusedFactor"
-    );
-    this.updateZoom(null, newScaleFactor, origin);
-  } else {
-    const PIXELS_PER_LINE_SCALE = 30;
-    const ticks = this._accumulateTicks(
-      (distance - pDistance) / PIXELS_PER_LINE_SCALE,
-      "_touchUnusedTicks"
-    );
-    this.updateZoom(ticks, null, origin);
-  }
-}
-
-function onTouchEnd(evt) {
-  if (!this._touchInfo) {
-    return;
-  }
-
-  evt.preventDefault();
-  this._touchInfo = null;
-  this._touchUnusedTicks = 0;
-  this._touchUnusedFactor = 1;
-  this._isPinching = false;
-}
-
 function closeSecondaryToolbar(evt) {
   if (!this.secondaryToolbar?.isOpen) {
     return;

web/pdfjs.js

@@ -53,6 +53,7 @@ const {
   shadow,
   stopEvent,
   TextLayer,
+  TouchManager,
   UnexpectedResponseException,
   Util,
   VerbosityLevel,
@@ -100,6 +101,7 @@ export {
   shadow,
   stopEvent,
   TextLayer,
+  TouchManager,
   UnexpectedResponseException,
   Util,
   VerbosityLevel,