| // Copyright 2018 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 "platform/scroll/ScrollCustomization.h" |
| |
| namespace blink { |
| namespace ScrollCustomization { |
| |
| ScrollDirection GetScrollDirectionFromDeltas(double delta_x, double delta_y) { |
| // TODO(ekaramad, tdresser): Find out the right value for kEpsilon here (see |
| // https://crbug.com/510550). |
| const double kEpsilon = 0.1f; |
| |
| ScrollDirection direction = kScrollDirectionNone; |
| if (delta_x > kEpsilon) |
| direction |= kScrollDirectionPanRight; |
| if (delta_x < -kEpsilon) |
| direction |= kScrollDirectionPanLeft; |
| if (delta_y > kEpsilon) |
| direction |= kScrollDirectionPanDown; |
| if (delta_y < -kEpsilon) |
| direction |= kScrollDirectionPanUp; |
| |
| if (!direction) { |
| // TODO(ekaramad, sahel): Remove this and perhaps replace with a DCHECK when |
| // issue https://crbug.com/728214 is fixed. |
| return kScrollDirectionAuto; |
| } |
| |
| return direction; |
| } |
| |
| } // namespace ScrollCustomization |
| } // namespace blink |
