cc/input/scroll_state.cc

   1 // Copyright 2015 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 "cc/input/scroll_state.h"
   6
   7 #include "cc/layers/layer_impl.h"
   8
   9 namespace cc {
  10
  11 ScrollState::ScrollState(double delta_x,
  12                          double delta_y,
  13                          int start_position_x,
  14                          int start_position_y,
  15                          bool should_propagate,
  16                          bool delta_consumed_for_scroll_sequence,
  17                          bool is_direct_manipulation)
  18     : delta_x_(delta_x),
  19       delta_y_(delta_y),
  20       start_position_x_(start_position_x),
  21       start_position_y_(start_position_y),
  22       should_propagate_(should_propagate),
  23       delta_consumed_for_scroll_sequence_(delta_consumed_for_scroll_sequence),
  24       is_direct_manipulation_(is_direct_manipulation),
  25       caused_scroll_x_(false),
  26       caused_scroll_y_(false) {}
  27
  28 ScrollState::~ScrollState() {}
  29
  30 void ScrollState::ConsumeDelta(double x, double y) {
  31   delta_x_ -= x;
  32   delta_y_ -= y;
  33
  34   if (x || y)
  35     delta_consumed_for_scroll_sequence_ = true;
  36 }
  37
  38 void ScrollState::DistributeToScrollChainDescendant() {
  39   if (!scroll_chain_.empty()) {
  40     LayerImpl* next = scroll_chain_.front();
  41     scroll_chain_.pop_front();
  42     next->DistributeScroll(this);
  43   }
  44 }
  45
  46 }  // namespace cc