touchui: support XInput2 MT

views/events/event_x.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "views/events/event.h"
 
 #include <gdk/gdk.h>
 #include <gdk/gdkx.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xlib.h>
@@ skipping 59 matching lines @@
   for (int i = 0; i < 8 * xievent->buttons.mask_len; i++) {
     if (XIMaskIsSet(xievent->buttons.mask, i)) {
       buttonflags |= GetEventFlagsForButton(i);
     }
   }
 
   return buttonflags;
 }
 
 ui::EventType GetTouchEventType(XEvent* xev) {
+#if defined(USE_XI2_MT)
+  XIEvent* event = static_cast<XIEvent*>(xev->xcookie.data);
+  switch(event->evtype) {
+    case XI_TouchBegin:
+      return ui::ET_TOUCH_PRESSED;
+    case XI_TouchUpdate:
+      return ui::ET_TOUCH_MOVED;
+    case XI_TouchEnd:
+      return ui::ET_TOUCH_RELEASED;
+  }
+
+  return ui::ET_UNKNOWN;
+#else
   XGenericEventCookie* cookie = &xev->xcookie;
   DCHECK_EQ(cookie->evtype, XI_Motion);
 
   // Note: We will not generate a _STATIONARY event here. It will be created,
   // when necessary, by a RWHVV.
   // TODO(sad): When should _CANCELLED be generated?
 
   TouchFactory* factory = TouchFactory::GetInstance();
   float slot;
   if (!factory->ExtractTouchParam(*xev, TouchFactory::TP_SLOT_ID, &slot))
     return ui::ET_UNKNOWN;
 
   if (!factory->IsSlotUsed(slot)) {
     // This is a new touch point.
     return ui::ET_TOUCH_PRESSED;
   }
 
   float tracking;
   if (!factory->ExtractTouchParam(*xev, TouchFactory::TP_TRACKING_ID,
         &tracking))
     return ui::ET_UNKNOWN;
 
   if (tracking == 0l) {
     // The touch point has been released.
     return ui::ET_TOUCH_RELEASED;
   }
 
   return ui::ET_TOUCH_MOVED;
+#endif  // defined(USE_XI2_MT)
 }
 
 int GetTouchIDFromXEvent(XEvent* xev) {
-  float slot = 0;
+  float id = 0;
+#if defined(USE_XI2_MT)
+  // TODO(ningxin.hu@gmail.com): Make the id always start from 0 for a new
+  // touch-sequence when TRACKING_ID is used to extract the touch id.
+  TouchFactory::TouchParam tp = TouchFactory::TP_TRACKING_ID;
+#else
+  TouchFactory::TouchParam tp = TouchFactory::TP_SLOT_ID;
+#endif
   if (!TouchFactory::GetInstance()->ExtractTouchParam(
-        *xev, TouchFactory::TP_SLOT_ID, &slot))
-    LOG(ERROR) << "Could not get the slot ID for the event. Using 0.";
-  return slot;
+          *xev, tp, &id))
+    LOG(ERROR) << "Could not get the touch ID for the event. Using 0.";
+  return id;
 }
 
 ui::EventType EventTypeFromNative(NativeEvent2 native_event) {
   switch (native_event->type) {
     case KeyPress:
       return ui::ET_KEY_PRESSED;
     case KeyRelease:
       return ui::ET_KEY_RELEASED;
     case ButtonPress:
       if (native_event->xbutton.button == 4 ||
@@ skipping 270 matching lines @@
       radius_x_(GetTouchParamFromXEvent(native_event_2,
                                         TouchFactory::TP_TOUCH_MAJOR,
                                         2.0) / 2.0),
       radius_y_(GetTouchParamFromXEvent(native_event_2,
                                         TouchFactory::TP_TOUCH_MINOR,
                                         2.0) / 2.0),
       rotation_angle_(GetTouchParamFromXEvent(native_event_2,
                                               TouchFactory::TP_ORIENTATION,
                                               0.0)),
       force_(GetTouchForceFromXEvent(native_event_2)) {
+#if !defined(USE_XI2_MT)
   if (type() == ui::ET_TOUCH_PRESSED || type() == ui::ET_TOUCH_RELEASED) {
     TouchFactory* factory = TouchFactory::GetInstance();
     float slot;
     if (factory->ExtractTouchParam(*native_event_2,
                                    TouchFactory::TP_SLOT_ID, &slot)) {
       factory->SetSlotUsed(slot, type() == ui::ET_TOUCH_PRESSED);
     }
   }
+#endif
 }
 
 }  // namespace views