Auto merge of #9811 - paulrouget:forceTouch, r=mbrubeck

forcetouch events

https://developer.apple.com/library/mac/documentation/AppleApplications/Conceptual/SafariJSProgTopics/RespondingtoForceTouchEventsfromJavaScript.html

Not sure how we want to land that yet. Maybe reproduce the webkit events (as in this PR), or as touch/mousemouse events.

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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"),