Add support for touch based zoom gesture on Windows. This change also handles the WM_POINTERDOWN

and WM_POINTERUP messages to scroll the page if we touch the scrollbar.

BUG=none
TEST=Touch based zoom should work on Windows.
Review URL: http://codereview.chromium.org/8399009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@108232 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_widget_host_view_win.cc

@@ -32,6 +32,7 @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/common/content_switches.h"
+#include "content/public/common/page_zoom.h"
 #include "skia/ext/skia_utils_win.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCompositionUnderline.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
@@ -201,8 +202,43 @@ LRESULT CALLBACK PluginWrapperWindowProc(HWND window, unsigned int message,
   return ::DefWindowProc(window, message, wparam, lparam);
 }
 
-bool DecodeScrollGesture(WPARAM wParam,
-                         LPARAM lParam,
+bool DecodeZoomGesture(HWND hwnd, const GESTUREINFO& gi,
+                       content::PageZoom* zoom,
+                       POINT* zoom_center) {
+  static long start = 0;
+  static POINT zoom_first;
+
+  if (gi.dwFlags == GF_BEGIN) {
+    start = gi.ullArguments;
+    zoom_first.x = gi.ptsLocation.x;
+    zoom_first.y = gi.ptsLocation.y;
+    ScreenToClient(hwnd, &zoom_first);
+    return false;
+  }
+
+  if (gi.dwFlags == GF_END)
+    return false;
+
+  POINT zoom_second = {0};
+  zoom_second.x = gi.ptsLocation.x;
+  zoom_second.y = gi.ptsLocation.y;
+  ScreenToClient(hwnd, &zoom_second);
+
+  zoom_center->x = (zoom_first.x + zoom_second.x) / 2;
+  zoom_center->y = (zoom_first.y + zoom_second.y) / 2;
+
+  double zoom_factor =
+      static_cast<double>(gi.ullArguments)/static_cast<double>(start);
+
+  *zoom = zoom_factor >= 1 ? content::PAGE_ZOOM_IN :
+              content::PAGE_ZOOM_OUT;
+
+  start = gi.ullArguments;
+  zoom_first = zoom_second;
+  return true;
+}
+
+bool DecodeScrollGesture(const GESTUREINFO& gi,
                          POINT* start,
                          POINT* delta){
   // Windows gestures are streams of messages with begin/end messages that
@@ -211,16 +247,6 @@ bool DecodeScrollGesture(WPARAM wParam,
   static POINT last_pt;
   static POINT start_pt;
 
-  GESTUREINFO gi = {sizeof(GESTUREINFO)};
-  HGESTUREINFO gi_handle = reinterpret_cast<HGESTUREINFO>(lParam);
-  if (!::GetGestureInfo(gi_handle, &gi)) {
-    DWORD error = GetLastError();
-    NOTREACHED() << "Unable to get gesture info. Error : " << error;
-  }
-
-  if (gi.dwID != GID_PAN)
-    return false;
-
   if (gi.dwFlags == GF_BEGIN) {
     delta->x = 0;
     delta->y = 0;
@@ -233,32 +259,31 @@ bool DecodeScrollGesture(WPARAM wParam,
   last_pt.x = gi.ptsLocation.x;
   last_pt.y = gi.ptsLocation.y;
   *start = start_pt;
-  ::CloseGestureInfoHandle(gi_handle);
   return true;
 }
 
 WebKit::WebMouseWheelEvent MakeFakeScrollWheelEvent(HWND hwnd,
                                                     POINT start,
                                                     POINT delta) {
-  WebKit::WebMouseWheelEvent result;
-  result.type = WebInputEvent::MouseWheel;
-  result.timeStampSeconds = ::GetMessageTime() / 1000.0;
-  result.button = WebMouseEvent::ButtonNone;
-  result.globalX = start.x;
-  result.globalY = start.y;
-  // Map to window coordinates.
-  POINT clientPoint = { result.globalX, result.globalY };
-  MapWindowPoints(0, hwnd, &clientPoint, 1);
-  result.x = clientPoint.x;
-  result.y = clientPoint.y;
-  result.windowX = result.x;
-  result.windowY = result.y;
-  // Note that we support diagonal scrolling.
-  result.deltaX = static_cast<float>(delta.x);
-  result.wheelTicksX = WHEEL_DELTA;
-  result.deltaY = static_cast<float>(delta.y);
-  result.wheelTicksY = WHEEL_DELTA;
-  return result;
+    WebKit::WebMouseWheelEvent result;
+    result.type = WebInputEvent::MouseWheel;
+    result.timeStampSeconds = ::GetMessageTime() / 1000.0;
+    result.button = WebMouseEvent::ButtonNone;
+    result.globalX = start.x;
+    result.globalY = start.y;
+    // Map to window coordinates.
+    POINT client_point = { result.globalX, result.globalY };
+    MapWindowPoints(0, hwnd, &client_point, 1);
+    result.x = client_point.x;
+    result.y = client_point.y;
+    result.windowX = result.x;
+    result.windowY = result.y;
+    // Note that we support diagonal scrolling.
+    result.deltaX = static_cast<float>(delta.x);
+    result.wheelTicksX = WHEEL_DELTA;
+    result.deltaY = static_cast<float>(delta.y);
+    result.wheelTicksY = WHEEL_DELTA;
+    return result;
 }
 
 }  // namespace
@@ -286,7 +311,9 @@ RenderWidgetHostViewWin::RenderWidgetHostViewWin(RenderWidgetHost* widget)
       text_input_type_(ui::TEXT_INPUT_TYPE_NONE),
       is_fullscreen_(false),
       ignore_mouse_movement_(true),
-      composition_range_(ui::Range::InvalidRange()) {
+      composition_range_(ui::Range::InvalidRange()),
+      ignore_next_lbutton_message_at_same_location(false),
+      last_pointer_down_location_(0) {
   render_widget_host_->SetView(this);
   registrar_.Add(this,
                  content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
@@ -299,7 +326,8 @@ RenderWidgetHostViewWin::~RenderWidgetHostViewWin() {
 }
 
 void RenderWidgetHostViewWin::CreateWnd(HWND parent) {
-  Create(parent);  // ATL function to create the window.
+  // ATL function to create the window.
+  Create(parent);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -1314,6 +1342,15 @@ LRESULT RenderWidgetHostViewWin::OnMouseEvent(UINT message, WPARAM wparam,
                                               LPARAM lparam, BOOL& handled) {
   handled = TRUE;
 
+  if (ignore_next_lbutton_message_at_same_location &&
+      message == WM_LBUTTONDOWN) {
+    ignore_next_lbutton_message_at_same_location = false;
+    LPARAM last_location = last_pointer_down_location_;
+    last_pointer_down_location_ = 0;
+    if (last_location == lparam)
+      return 0;
+  }
+
   if (message == WM_MOUSELEAVE)
     ignore_mouse_movement_ = true;
 
@@ -1566,18 +1603,38 @@ LRESULT RenderWidgetHostViewWin::OnMouseActivate(UINT message,
 }
 
 LRESULT RenderWidgetHostViewWin::OnGestureEvent(
-    UINT message, WPARAM wparam, LPARAM lparam, BOOL& handled) {
-  // Right now we only decode scroll gestures and we forward to the page
-  // as scroll events.
-  POINT start;
-  POINT delta;
-  if (DecodeScrollGesture(wparam, lparam, &start, &delta)) {
-    handled = TRUE;
-    render_widget_host_->ForwardWheelEvent(
-        MakeFakeScrollWheelEvent(m_hWnd, start, delta));
-  } else {
-    handled = FALSE;
+      UINT message, WPARAM wparam, LPARAM lparam, BOOL& handled) {
+
+  handled = FALSE;
+
+  GESTUREINFO gi = {sizeof(GESTUREINFO)};
+  HGESTUREINFO gi_handle = reinterpret_cast<HGESTUREINFO>(lparam);
+  if (!::GetGestureInfo(gi_handle, &gi)) {
+    DWORD error = GetLastError();
+    NOTREACHED() << "Unable to get gesture info. Error : " << error;
+    return 0;
+  }
+
+  if (gi.dwID == GID_ZOOM) {
+    content::PageZoom zoom = content::PAGE_ZOOM_RESET;
+    POINT zoom_center = {0};
+    if (DecodeZoomGesture(m_hWnd, gi, &zoom, &zoom_center)) {
+      handled = TRUE;
+      Send(new ViewMsg_ZoomFactor(render_widget_host_->routing_id(),
+                                  zoom, zoom_center.x, zoom_center.y));
+    }
+  } else if (gi.dwID == GID_PAN) {
+    // Right now we only decode scroll gestures and we forward to the page
+    // as scroll events.
+    POINT start;
+    POINT delta;
+    if (DecodeScrollGesture(gi, &start, &delta)) {
+      handled = TRUE;
+      render_widget_host_->ForwardWheelEvent(
+          MakeFakeScrollWheelEvent(m_hWnd, start, delta));
+    }
   }
+  ::CloseGestureInfoHandle(gi_handle);
   return 0;
 }
 
@@ -1862,6 +1919,27 @@ LRESULT RenderWidgetHostViewWin::OnParentNotify(UINT message, WPARAM wparam,
   return 0;
 }
 
+LRESULT RenderWidgetHostViewWin::OnPointerMessage(
+    UINT message, WPARAM wparam, LPARAM lparam, BOOL& handled) {
+  POINT point = {0};
+
+  point.x = GET_X_LPARAM(lparam);
+  point.y = GET_Y_LPARAM(lparam);
+  ScreenToClient(&point);
+
+  lparam = MAKELPARAM(point.x, point.y);
+
+  if (message == WM_POINTERDOWN) {
+    OnMouseEvent(WM_LBUTTONDOWN, MK_LBUTTON, lparam, handled);
+    ignore_next_lbutton_message_at_same_location = true;
+    last_pointer_down_location_ = lparam;
+  } else if (message == WM_POINTERUP) {
+    OnMouseEvent(WM_LBUTTONUP, MK_LBUTTON, lparam, handled);
+  }
+  handled = FALSE;
+  return 0;
+}
+
 void RenderWidgetHostViewWin::OnFinalMessage(HWND window) {
   // When the render widget host is being destroyed, it ends up calling
   // Destroy() which NULLs render_widget_host_.

content/browser/renderer_host/render_widget_host_view_win.h

@@ -50,6 +50,21 @@ typedef CWinTraits<WS_CHILD | WS_CLIPCHILDREN | WS_CLIPSIBLINGS, 0>
 
 CONTENT_EXPORT extern const wchar_t kRenderWidgetHostHWNDClass[];
 
+// TODO(ananta)
+// This should be removed once we have the new windows SDK which defines these
+// messages.
+#if !defined(WM_POINTERUPDATE)
+#define WM_POINTERUPDATE 0x0245
+#endif  // WM_POINTERUPDATE
+
+#if !defined(WM_POINTERDOWN)
+#define WM_POINTERDOWN  0x0246
+#endif  // WM_POINTERDOWN
+
+#if !defined(WM_POINTERUP)
+#define WM_POINTERUP    0x0247
+#endif  // WM_POINTERUP
+
 ///////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewWin
 //
@@ -130,6 +145,8 @@ class RenderWidgetHostViewWin
     MESSAGE_HANDLER(WM_MOUSEACTIVATE, OnMouseActivate)
     MESSAGE_HANDLER(WM_GETOBJECT, OnGetObject)
     MESSAGE_HANDLER(WM_PARENTNOTIFY, OnParentNotify)
+    MESSAGE_HANDLER(WM_POINTERDOWN, OnPointerMessage)
+    MESSAGE_HANDLER(WM_POINTERUP, OnPointerMessage)
     MESSAGE_HANDLER(WM_GESTURE, OnGestureEvent)
   END_MSG_MAP()
 
@@ -244,6 +261,10 @@ class RenderWidgetHostViewWin
 
   LRESULT OnParentNotify(UINT message, WPARAM wparam, LPARAM lparam,
                          BOOL& handled);
+
+  // Handle the new pointer messages
+  LRESULT OnPointerMessage(UINT message, WPARAM wparam, LPARAM lparam,
+                           BOOL& handled);
   // Handle high-level touch events.
   LRESULT OnGestureEvent(UINT message, WPARAM wparam, LPARAM lparam,
                          BOOL& handled);
@@ -420,6 +441,14 @@ class RenderWidgetHostViewWin
 
   ui::Range composition_range_;
 
+  // Set to true if the next lbutton down message is to be ignored. Set by the
+  // WM_POINTERXX handler. We do this to ensure that we don't send out
+  // duplicate lbutton down messages to the renderer.
+  bool ignore_next_lbutton_message_at_same_location;
+  // The location of the last WM_POINTERDOWN message. We ignore the subsequent
+  // lbutton down only if the locations match.
+  LPARAM last_pointer_down_location_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewWin);
 };
 

content/common/view_messages.h

@@ -921,6 +921,12 @@ IPC_MESSAGE_ROUTED1(ViewMsg_Zoom,
 IPC_MESSAGE_ROUTED1(ViewMsg_SetZoomLevel,
                     double /* zoom_level */)
 
+// Zooms the page by the factor defined in the renderer.
+IPC_MESSAGE_ROUTED3(ViewMsg_ZoomFactor,
+                    content::PageZoom,
+                    int /* zoom center_x */,
+                    int /* zoom center_y */)
+
 // Set the zoom level for a particular url that the renderer is in the
 // process of loading.  This will be stored, to be used if the load commits
 // and ignored otherwise.

content/renderer/render_view_impl.cc

@@ -271,6 +271,8 @@ static const int kMaximumNumberOfUnacknowledgedPopups = 25;
 
 static const float kScalingIncrement = 0.1f;
 
+static const float kScalingIncrementForGesture = 0.01f;
+
 static void GetRedirectChain(WebDataSource* ds, std::vector<GURL>* result) {
   WebVector<WebURL> urls;
   ds->redirectChain(urls);
@@ -599,6 +601,7 @@ bool RenderViewImpl::OnMessageReceived(const IPC::Message& message) {
     IPC_MESSAGE_HANDLER(ViewMsg_FindReplyACK, OnFindReplyAck)
     IPC_MESSAGE_HANDLER(ViewMsg_Zoom, OnZoom)
     IPC_MESSAGE_HANDLER(ViewMsg_SetZoomLevel, OnSetZoomLevel)
+    IPC_MESSAGE_HANDLER(ViewMsg_ZoomFactor, OnZoomFactor)
     IPC_MESSAGE_HANDLER(ViewMsg_SetZoomLevelForLoadingURL,
                         OnSetZoomLevelForLoadingURL)
     IPC_MESSAGE_HANDLER(ViewMsg_ExitFullscreen, OnExitFullscreen)
@@ -3553,17 +3556,36 @@ void RenderViewImpl::OnZoom(content::PageZoom zoom) {
   }
   webview()->setZoomLevel(false, zoom_level);
 #else
+  ZoomFactorHelper(function, 0, 0, kScalingIncrement);
+#endif
+  zoomLevelChanged();
+}
+
+void RenderViewImpl::OnZoomFactor(content::PageZoom zoom,
+                                  int zoom_center_x, int zoom_center_y) {
+  ZoomFactorHelper(zoom, zoom_center_x, zoom_center_y,
+                   kScalingIncrementForGesture);
+}
+
+void RenderViewImpl::ZoomFactorHelper(content::PageZoom zoom,
+                                      int zoom_center_x,
+                                      int zoom_center_y,
+                                      float scaling_increment) {
+  if (!webview())  // Not sure if this can happen, but no harm in being safe.
+    return;
+
   double old_page_scale_factor = webview()->pageScaleFactor();
   double page_scale_factor;
   if (zoom == content::PAGE_ZOOM_RESET) {
     page_scale_factor = 1.0;
   } else {
     page_scale_factor = old_page_scale_factor +
-        (zoom > 0 ? kScalingIncrement : -kScalingIncrement);
+        (zoom > 0 ? scaling_increment : -scaling_increment);
+  }
+  if (page_scale_factor > 0) {
+    webview()->scalePage(page_scale_factor,
+                         WebPoint(zoom_center_x, zoom_center_y));
   }
-  webview()->scalePage(page_scale_factor, WebPoint(0, 0));
-#endif
-  zoomLevelChanged();
 }
 
 void RenderViewImpl::OnSetZoomLevel(double zoom_level) {

content/renderer/render_view_impl.h

@@ -860,6 +860,9 @@ class RenderViewImpl : public RenderWidget,
   void OnSelectPopupMenuItem(int selected_index);
 #endif
   void OnZoom(content::PageZoom zoom);
+  void OnZoomFactor(content::PageZoom zoom, int zoom_center_x,
+                    int zoom_center_y);
+
   void OnEnableViewSourceMode();
 
   void OnJavaBridgeInit(const IPC::ChannelHandle& channel_handle);
@@ -868,6 +871,8 @@ class RenderViewImpl : public RenderWidget,
   // and put it in the same position in the .cc file.
 
   // Misc private functions ----------------------------------------------------
+  void ZoomFactorHelper(content::PageZoom zoom, int zoom_center_x,
+                        int zoom_center_y, float scaling_increment);
 
   void AltErrorPageFinished(WebKit::WebFrame* frame,
                             const WebKit::WebURLError& original_error,