forcetouch events support

This enables Apple forcetouch DOM events. It requires the preference dom.forcetouch.enabled.

The DOM events are described here:
- https://developer.apple.com/library/mac/documentation/AppleApplications/Conceptual/SafariJSProgTopics/RespondingtoForceTouchEventsfromJavaScript.html

The Cocoa mechanism is documented here:
- https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSEvent_Class/#//apple_ref/doc/uid/20000016-SW274

components/compositing/compositor.rs

@@ -37,7 +37,7 @@ use profile_traits::mem::{self, ReportKind, Reporter, ReporterRequest};
 use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{MouseMoveEvent, MouseButtonEvent, TouchEvent};
 use script_traits::{AnimationState, ConstellationControlMsg, LayoutControlMsg};
-use script_traits::{MouseButton, MouseEventType, TouchEventType, TouchId};
+use script_traits::{MouseButton, MouseEventType, TouchpadPressurePhase, TouchEventType, TouchId};
 use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::collections::{HashMap, HashSet};
 use std::fs::File;
@@ -50,8 +50,8 @@ use time::{precise_time_ns, precise_time_s};
 use touch::{TouchHandler, TouchAction};
 use url::Url;
 use util::geometry::{PagePx, ScreenPx, ViewportPx};
-use util::opts;
 use util::print_tree::PrintTree;
+use util::{opts, prefs};
 use webrender;
 use webrender_traits::{self, ScrollEventPhase};
 use windowing::{self, MouseWindowEvent, WindowEvent, WindowMethods, WindowNavigateMsg};
@@ -1225,6 +1225,10 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.on_navigation_window_event(direction);
             }
 
+            WindowEvent::TouchpadPressure(cursor, pressure, stage) => {
+                self.on_touchpad_pressure_event(cursor, pressure, stage);
+            }
+
             WindowEvent::KeyEvent(key, state, modifiers) => {
                 self.on_key_event(key, state, modifiers);
             }
@@ -1701,6 +1705,16 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         self.constellation_chan.send(ConstellationMsg::Navigate(None, direction)).unwrap()
     }
 
+    fn on_touchpad_pressure_event(&self, cursor: TypedPoint2D<DevicePixel, f32>, pressure: f32,
+                                  phase: TouchpadPressurePhase) {
+        if prefs::get_pref("dom.forcetouch.enabled").as_boolean().unwrap() {
+            match self.find_topmost_layer_at_point(cursor / self.scene.scale) {
+                Some(result) => result.layer.send_touchpad_pressure_event(self, result.point, pressure, phase),
+                None => {},
+            }
+        }
+    }
+
     fn on_key_event(&self, key: Key, state: KeyState, modifiers: KeyModifiers) {
         self.constellation_chan.send(ConstellationMsg::KeyEvent(key, state, modifiers)).unwrap()
     }

components/compositing/compositor_layer.rs

@@ -14,9 +14,10 @@ use layers::geometry::LayerPixel;
 use layers::layers::{Layer, LayerBufferSet};
 use msg::constellation_msg::PipelineId;
 use script_traits::CompositorEvent;
-use script_traits::CompositorEvent::{MouseButtonEvent, MouseMoveEvent};
+use script_traits::CompositorEvent::{MouseButtonEvent, MouseMoveEvent, TouchpadPressureEvent};
 use script_traits::ConstellationControlMsg;
 use script_traits::MouseEventType;
+use script_traits::TouchpadPressurePhase;
 use std::rc::Rc;
 use windowing::{MouseWindowEvent, WindowMethods};
 
@@ -139,6 +140,13 @@ pub trait CompositorLayer {
                           event: CompositorEvent)
                           where Window: WindowMethods;
 
+    fn send_touchpad_pressure_event<Window>(&self,
+                                            compositor: &IOCompositor<Window>,
+                                            cursor: TypedPoint2D<LayerPixel, f32>,
+                                            pressure: f32,
+                                            phase: TouchpadPressurePhase)
+                                            where Window: WindowMethods;
+
     fn clamp_scroll_offset_and_scroll_layer(&self,
                                             new_offset: TypedPoint2D<LayerPixel, f32>)
                                             -> ScrollEventResult;
@@ -399,6 +407,18 @@ impl CompositorLayer for Layer<CompositorData> {
         }
     }
 
+    fn send_touchpad_pressure_event<Window>(&self,
+                                            compositor: &IOCompositor<Window>,
+                                            cursor: TypedPoint2D<LayerPixel, f32>,
+                                            pressure: f32,
+                                            phase: TouchpadPressurePhase)
+                                            where Window: WindowMethods {
+        if let Some(pipeline) = compositor.pipeline(self.pipeline_id()) {
+            let message = TouchpadPressureEvent(cursor.to_untyped(), pressure, phase);
+            let _ = pipeline.script_chan.send(ConstellationControlMsg::SendEvent(pipeline.id.clone(), message));
+        }
+    }
+
     fn scroll_layer_and_all_child_layers(&self, new_offset: TypedPoint2D<LayerPixel, f32>)
                                          -> bool {
         let mut result = false;

components/compositing/windowing.rs

@@ -13,7 +13,7 @@ use layers::geometry::DevicePixel;
 use layers::platform::surface::NativeDisplay;
 use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use net_traits::net_error_list::NetError;
-use script_traits::{MouseButton, TouchEventType, TouchId};
+use script_traits::{MouseButton, TouchpadPressurePhase, TouchEventType, TouchId};
 use std::fmt::{Debug, Error, Formatter};
 use style_traits::cursor::Cursor;
 use url::Url;
@@ -50,6 +50,8 @@ pub enum WindowEvent {
     InitializeCompositing,
     /// Sent when the window is resized.
     Resize(TypedSize2D<DevicePixel, u32>),
+    /// Touchpad Pressure
+    TouchpadPressure(TypedPoint2D<DevicePixel, f32>, f32, TouchpadPressurePhase),
     /// Sent when you want to override the viewport.
     Viewport(TypedPoint2D<DevicePixel, u32>, TypedSize2D<DevicePixel, u32>),
     /// Sent when a new URL is to be loaded.
@@ -84,6 +86,7 @@ impl Debug for WindowEvent {
             WindowEvent::Refresh => write!(f, "Refresh"),
             WindowEvent::InitializeCompositing => write!(f, "InitializeCompositing"),
             WindowEvent::Resize(..) => write!(f, "Resize"),
+            WindowEvent::TouchpadPressure(..) => write!(f, "TouchpadPressure"),
             WindowEvent::Viewport(..) => write!(f, "Viewport"),
             WindowEvent::KeyEvent(..) => write!(f, "Key"),
             WindowEvent::LoadUrl(..) => write!(f, "LoadUrl"),

components/script/dom/bindings/trace.rs

@@ -64,7 +64,7 @@ use net_traits::storage_thread::StorageType;
 use profile_traits::mem::ProfilerChan as MemProfilerChan;
 use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_thread::ScriptChan;
-use script_traits::{LayoutMsg, ScriptMsg, TimerEventId, TimerSource, UntrustedNodeAddress};
+use script_traits::{LayoutMsg, ScriptMsg, TimerEventId, TimerSource, TouchpadPressurePhase, UntrustedNodeAddress};
 use serde::{Deserialize, Serialize};
 use smallvec::SmallVec;
 use std::boxed::FnBox;
@@ -319,6 +319,7 @@ no_jsmanaged_fields!(AttrIdentifier);
 no_jsmanaged_fields!(AttrValue);
 no_jsmanaged_fields!(ElementSnapshot);
 no_jsmanaged_fields!(HttpsState);
+no_jsmanaged_fields!(TouchpadPressurePhase);
 
 impl JSTraceable for ConstellationChan<ScriptMsg> {
     #[inline]

components/script/dom/document.rs

@@ -41,6 +41,7 @@ use dom::element::{Element, ElementCreator};
 use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
 use dom::focusevent::FocusEvent;
+use dom::forcetouchevent::ForceTouchEvent;
 use dom::htmlanchorelement::HTMLAnchorElement;
 use dom::htmlappletelement::HTMLAppletElement;
 use dom::htmlareaelement::HTMLAreaElement;
@@ -97,7 +98,7 @@ use script_thread::{MainThreadScriptChan, MainThreadScriptMsg, Runnable, ScriptC
 use script_traits::UntrustedNodeAddress;
 use script_traits::{AnimationState, MouseButton, MouseEventType, MozBrowserEvent};
 use script_traits::{ScriptMsg as ConstellationMsg, ScriptToCompositorMsg};
-use script_traits::{TouchEventType, TouchId};
+use script_traits::{TouchpadPressurePhase, TouchEventType, TouchId};
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::boxed::FnBox;
@@ -218,6 +219,7 @@ pub struct Document {
     css_errors_store: DOMRefCell<Vec<CSSError>>,
     /// https://html.spec.whatwg.org/multipage/#concept-document-https-state
     https_state: Cell<HttpsState>,
+    touchpad_pressure_phase: Cell<TouchpadPressurePhase>,
 }
 
 #[derive(JSTraceable, HeapSizeOf)]
@@ -732,6 +734,70 @@ impl Document {
                            ReflowReason::MouseEvent);
     }
 
+    pub fn handle_touchpad_pressure_event(&self,
+                                          js_runtime: *mut JSRuntime,
+                                          client_point: Point2D<f32>,
+                                          pressure: f32,
+                                          phase_now: TouchpadPressurePhase) {
+
+        let phase_before = self.touchpad_pressure_phase.get();
+        self.touchpad_pressure_phase.set(phase_now);
+
+        if phase_before == TouchpadPressurePhase::BeforeClick &&
+           phase_now == TouchpadPressurePhase::BeforeClick {
+            return;
+        }
+
+        let page_point = Point2D::new(client_point.x + self.window.PageXOffset() as f32,
+                                      client_point.y + self.window.PageYOffset() as f32);
+        let node = match self.window.hit_test_query(page_point, false) {
+            Some(node_address) => node::from_untrusted_node_address(js_runtime, node_address),
+            None => return
+        };
+
+        let el = match node.downcast::<Element>() {
+            Some(el) => Root::from_ref(el),
+            None => {
+                let parent = node.GetParentNode();
+                match parent.and_then(Root::downcast::<Element>) {
+                    Some(parent) => parent,
+                    None => return
+                }
+            },
+        };
+
+        let node = el.upcast::<Node>();
+        let target = node.upcast();
+
+        let force = match phase_now {
+            TouchpadPressurePhase::BeforeClick => pressure,
+            TouchpadPressurePhase::AfterFirstClick => 1. + pressure,
+            TouchpadPressurePhase::AfterSecondClick => 2. + pressure,
+        };
+
+        if phase_now != TouchpadPressurePhase::BeforeClick {
+            self.fire_forcetouch_event("servomouseforcechanged".to_owned(), target, force);
+        }
+
+        if phase_before != TouchpadPressurePhase::AfterSecondClick &&
+           phase_now == TouchpadPressurePhase::AfterSecondClick {
+            self.fire_forcetouch_event("servomouseforcedown".to_owned(), target, force);
+        }
+
+        if phase_before == TouchpadPressurePhase::AfterSecondClick &&
+           phase_now != TouchpadPressurePhase::AfterSecondClick {
+            self.fire_forcetouch_event("servomouseforceup".to_owned(), target, force);
+        }
+    }
+
+    fn fire_forcetouch_event(&self, event_name: String, target: &EventTarget, force: f32) {
+        let force_event = ForceTouchEvent::new(&self.window,
+                                               DOMString::from(event_name),
+                                               force);
+        let event = force_event.upcast::<Event>();
+        event.fire(target);
+    }
+
     pub fn fire_mouse_event(&self, client_point: Point2D<f32>, target: &EventTarget, event_name: String) {
         let client_x = client_point.x.to_i32().unwrap_or(0);
         let client_y = client_point.y.to_i32().unwrap_or(0);
@@ -1593,6 +1659,7 @@ impl Document {
             dom_complete: Cell::new(Default::default()),
             css_errors_store: DOMRefCell::new(vec![]),
             https_state: Cell::new(HttpsState::None),
+            touchpad_pressure_phase: Cell::new(TouchpadPressurePhase::BeforeClick),
         }
     }
 

components/script/dom/forcetouchevent.rs

@@ -0,0 +1,59 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use dom::bindings::codegen::Bindings::ForceTouchEventBinding;
+use dom::bindings::codegen::Bindings::ForceTouchEventBinding::ForceTouchEventMethods;
+use dom::bindings::codegen::Bindings::UIEventBinding::UIEventMethods;
+use dom::bindings::global::GlobalRef;
+use dom::bindings::inheritance::Castable;
+use dom::bindings::js::{Root};
+use dom::bindings::num::Finite;
+use dom::bindings::reflector::reflect_dom_object;
+use dom::uievent::UIEvent;
+use dom::window::Window;
+use util::str::DOMString;
+
+#[dom_struct]
+pub struct ForceTouchEvent {
+    uievent: UIEvent,
+    force: f32,
+}
+
+impl ForceTouchEvent {
+    fn new_inherited(force: f32) -> ForceTouchEvent {
+        ForceTouchEvent {
+            uievent: UIEvent::new_inherited(),
+            force: force,
+        }
+    }
+
+    pub fn new(window: &Window,
+               type_: DOMString,
+               force: f32) -> Root<ForceTouchEvent> {
+        let event = box ForceTouchEvent::new_inherited(force);
+        let ev = reflect_dom_object(event, GlobalRef::Window(window), ForceTouchEventBinding::Wrap);
+        ev.upcast::<UIEvent>().InitUIEvent(type_, true, true, Some(window), 0);
+        ev
+    }
+}
+
+impl<'a> ForceTouchEventMethods for &'a ForceTouchEvent {
+
+    fn ServoForce(&self) -> Finite<f32> {
+        Finite::wrap(self.force)
+    }
+
+    fn SERVO_FORCE_AT_MOUSE_DOWN(&self) -> Finite<f32> {
+        Finite::wrap(1.0)
+    }
+
+    fn SERVO_FORCE_AT_FORCE_MOUSE_DOWN(&self) -> Finite<f32> {
+        Finite::wrap(2.0)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-event-istrusted
+    fn IsTrusted(&self) -> bool {
+        self.uievent.IsTrusted()
+    }
+}

components/script/dom/mod.rs

@@ -264,6 +264,7 @@ pub mod file;
 pub mod filelist;
 pub mod filereader;
 pub mod focusevent;
+pub mod forcetouchevent;
 pub mod formdata;
 pub mod htmlanchorelement;
 pub mod htmlappletelement;

components/script/dom/webidls/ForceTouchEvent.webidl

@@ -0,0 +1,35 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// https://developer.apple.com/library/mac/documentation/AppleApplications/Conceptual/SafariJSProgTopics/RespondingtoForceTouchEventsfromJavaScript.html
+
+/**
+ * Events: (copy/paste from apple.com)
+ *
+ *  webkitmouseforcewillbegin: This event occurs immediately before the mousedown event. It allows you to
+ *   prevent the default system behavior, such as displaying a dictionary window when force clicking on a
+ *   word, in order to perform a custom action instead. To prevent the default system behavior, call the
+ *   preventDefault() method on the event.
+ *  webkitmouseforcedown: This event occurs after the mousedown event, once enough force has been applied
+ *   to register as a force click. The user receives haptic feedback representing the force click when this
+ *   event occurs.
+ *  webkitmouseforceup: This event occurs after a webkitmouseforcedown event, once enough force has been
+ *   released to exit the force click operation. The user receives haptic feedback representing the exit
+ *   from force click when this event occurs.
+ *  webkitmouseforcechanged: This event occurs whenever a change in trackpad force is detected between the
+ *   mousedown and mouseup events.
+ *
+ */
+
+
+[Pref="dom.forcetouch.enabled"]
+interface ForceTouchEvent : UIEvent {
+    // Represents the amount of force required to perform a regular click.
+    readonly attribute float SERVO_FORCE_AT_MOUSE_DOWN;
+    // Represents the force required to perform a force click.
+    readonly attribute float SERVO_FORCE_AT_FORCE_MOUSE_DOWN;
+    // force level
+    readonly attribute float servoForce;
+};

components/script/script_thread.rs

@@ -79,7 +79,7 @@ use parse::xml::{self, parse_xml};
 use profile_traits::mem::{self, OpaqueSender, Report, ReportKind, ReportsChan};
 use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{KeyEvent, MouseButtonEvent, MouseMoveEvent, ResizeEvent};
-use script_traits::CompositorEvent::{TouchEvent};
+use script_traits::CompositorEvent::{TouchEvent, TouchpadPressureEvent};
 use script_traits::{CompositorEvent, ConstellationControlMsg, EventResult};
 use script_traits::{InitialScriptState, MouseButton, MouseEventType, MozBrowserEvent, NewLayoutInfo};
 use script_traits::{LayoutMsg, OpaqueScriptLayoutChannel, ScriptMsg as ConstellationMsg};
@@ -1969,6 +1969,12 @@ impl ScriptThread {
                 }
             }
 
+            TouchpadPressureEvent(point, pressure, phase) => {
+                let page = get_page(&self.root_page(), pipeline_id);
+                let document = page.document();
+                document.r().handle_touchpad_pressure_event(self.js_runtime.rt(), point, pressure, phase);
+            }
+
             KeyEvent(key, state, modifiers) => {
                 let page = get_page(&self.root_page(), pipeline_id);
                 let document = page.document();

components/script_traits/lib.rs

@@ -227,10 +227,23 @@ pub enum CompositorEvent {
     MouseMoveEvent(Option<Point2D<f32>>),
     /// A touch event was generated with a touch ID and location.
     TouchEvent(TouchEventType, TouchId, Point2D<f32>),
+    /// Touchpad pressure event
+    TouchpadPressureEvent(Point2D<f32>, f32, TouchpadPressurePhase),
     /// A key was pressed.
     KeyEvent(Key, KeyState, KeyModifiers),
 }
 
+/// Touchpad pressure phase for TouchpadPressureEvent.
+#[derive(Copy, Clone, HeapSizeOf, PartialEq, Deserialize, Serialize)]
+pub enum TouchpadPressurePhase {
+    /// Pressure before a regular click.
+    BeforeClick,
+    /// Pressure after a regular click.
+    AfterFirstClick,
+    /// Pressure after a "forceTouch" click
+    AfterSecondClick,
+}
+
 /// An opaque wrapper around script<->layout channels to avoid leaking message types into
 /// crates that don't need to know about them.
 pub struct OpaqueScriptLayoutChannel(pub (Box<Any + Send>, Box<Any + Send>));