1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "content/browser/renderer_host/basic_mouse_wheel_smooth_scroll_gesture.h" 6 7 #include "base/debug/trace_event.h" 8 #include "content/browser/renderer_host/render_widget_host_impl.h" 9 10 namespace content { 11 12 BasicMouseWheelSmoothScrollGesture::BasicMouseWheelSmoothScrollGesture( 13 bool scroll_down, int pixels_to_scroll, 14 int mouse_event_x, int mouse_event_y) 15 : scroll_down_(scroll_down), 16 pixels_scrolled_(0), 17 pixels_to_scroll_(pixels_to_scroll), 18 mouse_event_x_(mouse_event_x), 19 mouse_event_y_(mouse_event_y) { } 20 21 BasicMouseWheelSmoothScrollGesture::~BasicMouseWheelSmoothScrollGesture() { } 22 23 bool BasicMouseWheelSmoothScrollGesture::ForwardInputEvents( 24 base::TimeTicks now, RenderWidgetHost* host) { 25 26 if (pixels_scrolled_ >= pixels_to_scroll_) 27 return false; 28 29 double position_delta = smooth_scroll_calculator_.GetScrollDelta( 30 now, 31 RenderWidgetHostImpl::From(host)->GetSyntheticScrollMessageInterval()); 32 33 34 WebKit::WebMouseWheelEvent event; 35 event.type = WebKit::WebInputEvent::MouseWheel; 36 event.hasPreciseScrollingDeltas = 0; 37 event.deltaY = scroll_down_ ? -position_delta : position_delta; 38 // TODO(vollick): find a proper way to access 39 // WebCore::WheelEvent::tickMultiplier. 40 event.wheelTicksY = event.deltaY / 120; 41 event.modifiers = 0; 42 43 // TODO(nduca): Figure out plausible x and y values. 44 event.globalX = 0; 45 event.globalY = 0; 46 event.x = mouse_event_x_; 47 event.y = mouse_event_y_; 48 event.windowX = event.x; 49 event.windowY = event.y; 50 host->ForwardWheelEvent(event); 51 52 pixels_scrolled_ += abs(event.deltaY); 53 54 TRACE_COUNTER_ID1( 55 "gpu", "smooth_scroll_by_pixels_scrolled", this, pixels_scrolled_); 56 57 return true; 58 } 59 60 } // content 61 62
