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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef mozilla_gfx_layers_ScrollbarData_h
#define mozilla_gfx_layers_ScrollbarData_h
#include "FrameMetrics.h"
#include "mozilla/Maybe.h"
#include "mozilla/gfx/Types.h"
#include "mozilla/layers/LayersTypes.h"
#include "mozilla/layers/ScrollableLayerGuid.h"
namespace IPC {
template <typename T>
struct ParamTraits;
} // namespace IPC
namespace mozilla {
namespace layers {
// clang-format off
MOZ_DEFINE_ENUM_CLASS_WITH_BASE(ScrollbarLayerType, uint8_t, (
None,
Thumb,
Container
));
// clang-format on
/**
* It stores data for scroll thumb layer or container layers.
*/
struct ScrollbarData {
private:
/**
* This constructor is for Thumb layer type.
*/
ScrollbarData(ScrollDirection aDirection, float aThumbRatio,
OuterCSSCoord aThumbStart, OuterCSSCoord aThumbLength,
OuterCSSCoord aThumbMinLength, bool aThumbIsAsyncDraggable,
OuterCSSCoord aScrollTrackStart,
OuterCSSCoord aScrollTrackLength, uint64_t aTargetViewId)
: mDirection(Some(aDirection)),
mScrollbarLayerType(ScrollbarLayerType::Thumb),
mThumbRatio(aThumbRatio),
mThumbStart(aThumbStart),
mThumbLength(aThumbLength),
mThumbMinLength(aThumbMinLength),
mThumbIsAsyncDraggable(aThumbIsAsyncDraggable),
mScrollTrackStart(aScrollTrackStart),
mScrollTrackLength(aScrollTrackLength),
mTargetViewId(aTargetViewId) {}
/**
* This constructor is for Container layer type.
*/
ScrollbarData(const Maybe<ScrollDirection>& aDirection,
uint64_t aTargetViewId)
: mDirection(aDirection),
mScrollbarLayerType(ScrollbarLayerType::Container),
mTargetViewId(aTargetViewId) {}
public:
ScrollbarData() = default;
static ScrollbarData CreateForThumb(
ScrollDirection aDirection, float aThumbRatio, OuterCSSCoord aThumbStart,
OuterCSSCoord aThumbLength, OuterCSSCoord aThumbMinLength,
bool aThumbIsAsyncDraggable, OuterCSSCoord aScrollTrackStart,
OuterCSSCoord aScrollTrackLength, uint64_t aTargetViewId) {
return ScrollbarData(aDirection, aThumbRatio, aThumbStart, aThumbLength,
aThumbMinLength, aThumbIsAsyncDraggable,
aScrollTrackStart, aScrollTrackLength, aTargetViewId);
}
static ScrollbarData CreateForScrollbarContainer(
const Maybe<ScrollDirection>& aDirection, uint64_t aTargetViewId) {
return ScrollbarData(aDirection, aTargetViewId);
}
/**
* The mDirection contains a direction if mScrollbarLayerType is Thumb
* or Container, otherwise it's empty.
*/
Maybe<ScrollDirection> mDirection;
/**
* Indicate what kind of layer this data is for. All possibilities are defined
* in enum ScrollbarLayerType
*/
ScrollbarLayerType mScrollbarLayerType = ScrollbarLayerType::None;
/**
* The scrollbar thumb ratio is the ratio of the thumb position (in the CSS
* pixels of the scrollframe's parent's space) to the scroll position (in the
* CSS pixels of the scrollframe's space).
*/
float mThumbRatio = 0.0f;
OuterCSSCoord mThumbStart;
OuterCSSCoord mThumbLength;
OuterCSSCoord mThumbMinLength;
/**
* Whether the scrollbar thumb can be dragged asynchronously.
*/
bool mThumbIsAsyncDraggable = false;
OuterCSSCoord mScrollTrackStart;
OuterCSSCoord mScrollTrackLength;
uint64_t mTargetViewId = ScrollableLayerGuid::NULL_SCROLL_ID;
bool operator==(const ScrollbarData& aOther) const {
return mDirection == aOther.mDirection &&
mScrollbarLayerType == aOther.mScrollbarLayerType &&
mThumbRatio == aOther.mThumbRatio &&
mThumbStart == aOther.mThumbStart &&
mThumbLength == aOther.mThumbLength &&
mThumbMinLength == aOther.mThumbMinLength &&
mThumbIsAsyncDraggable == aOther.mThumbIsAsyncDraggable &&
mScrollTrackStart == aOther.mScrollTrackStart &&
mScrollTrackLength == aOther.mScrollTrackLength &&
mTargetViewId == aOther.mTargetViewId;
}
bool operator!=(const ScrollbarData& aOther) const {
return !(*this == aOther);
}
bool IsThumb() const {
return mScrollbarLayerType == ScrollbarLayerType::Thumb;
}
};
} // namespace layers
} // namespace mozilla
#endif // mozilla_gfx_layers_ScrollbarData_h