| // Copyright 2015 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 "cc/layers/viewport.h" |
| |
| #include "base/logging.h" |
| #include "cc/input/top_controls_manager.h" |
| #include "cc/trees/layer_tree_host_impl.h" |
| #include "cc/trees/layer_tree_impl.h" |
| #include "ui/gfx/geometry/vector2d_conversions.h" |
| #include "ui/gfx/geometry/vector2d_f.h" |
| |
| namespace cc { |
| |
| // static |
| scoped_ptr<Viewport> Viewport::Create( |
| LayerTreeHostImpl* host_impl) { |
| return make_scoped_ptr(new Viewport(host_impl)); |
| } |
| |
| Viewport::Viewport(LayerTreeHostImpl* host_impl) |
| : host_impl_(host_impl) |
| , pinch_zoom_active_(false) { |
| DCHECK(host_impl_); |
| } |
| |
| void Viewport::Pan(const gfx::Vector2dF& delta) { |
| gfx::Vector2dF pending_delta = delta; |
| float page_scale = host_impl_->active_tree()->current_page_scale_factor(); |
| pending_delta.Scale(1 / page_scale); |
| InnerScrollLayer()->ScrollBy(pending_delta); |
| } |
| |
| Viewport::ScrollResult Viewport::ScrollBy(const gfx::Vector2dF& delta, |
| const gfx::Point& viewport_point, |
| bool is_direct_manipulation, |
| bool affect_top_controls) { |
| gfx::Vector2dF content_delta = delta; |
| |
| if (affect_top_controls && ShouldTopControlsConsumeScroll(delta)) |
| content_delta -= ScrollTopControls(delta); |
| |
| gfx::Vector2dF pending_content_delta = content_delta; |
| |
| bool invert_scroll_order = |
| host_impl_->settings().invert_viewport_scroll_order; |
| LayerImpl* primary_layer = |
| invert_scroll_order ? InnerScrollLayer() : OuterScrollLayer(); |
| LayerImpl* secondary_layer = |
| invert_scroll_order ? OuterScrollLayer() : InnerScrollLayer(); |
| |
| pending_content_delta -= host_impl_->ScrollLayer(primary_layer, |
| pending_content_delta, |
| viewport_point, |
| is_direct_manipulation); |
| |
| ScrollResult result; |
| |
| // TODO(bokan): This shouldn't be needed but removing it causes subtle |
| // viewport movement during top controls manipulation. |
| if (gfx::ToRoundedVector2d(pending_content_delta).IsZero()) { |
| result.consumed_delta = delta; |
| } else { |
| pending_content_delta -= host_impl_->ScrollLayer(secondary_layer, |
| pending_content_delta, |
| viewport_point, |
| is_direct_manipulation); |
| result.consumed_delta = delta - AdjustOverscroll(pending_content_delta); |
| } |
| |
| result.content_scrolled_delta = content_delta - pending_content_delta; |
| return result; |
| } |
| |
| void Viewport::SnapPinchAnchorIfWithinMargin(const gfx::Point& anchor) { |
| gfx::SizeF viewport_size = |
| host_impl_->active_tree()->InnerViewportContainerLayer()->bounds(); |
| |
| if (anchor.x() < kPinchZoomSnapMarginDips) |
| pinch_anchor_adjustment_.set_x(-anchor.x()); |
| else if (anchor.x() > viewport_size.width() - kPinchZoomSnapMarginDips) |
| pinch_anchor_adjustment_.set_x(viewport_size.width() - anchor.x()); |
| |
| if (anchor.y() < kPinchZoomSnapMarginDips) |
| pinch_anchor_adjustment_.set_y(-anchor.y()); |
| else if (anchor.y() > viewport_size.height() - kPinchZoomSnapMarginDips) |
| pinch_anchor_adjustment_.set_y(viewport_size.height() - anchor.y()); |
| } |
| |
| void Viewport::PinchUpdate(float magnify_delta, const gfx::Point& anchor) { |
| if (!pinch_zoom_active_) { |
| // If this is the first pinch update and the pinch is within a margin- |
| // length of the screen edge, offset all updates by the amount so that we |
| // effectively snap the pinch zoom to the edge of the screen. This makes it |
| // easy to zoom in on position: fixed elements. |
| if (host_impl_->settings().invert_viewport_scroll_order) |
| SnapPinchAnchorIfWithinMargin(anchor); |
| |
| pinch_zoom_active_ = true; |
| } |
| |
| LayerTreeImpl* active_tree = host_impl_->active_tree(); |
| |
| // Keep the center-of-pinch anchor specified by (x, y) in a stable |
| // position over the course of the magnify. |
| gfx::Point adjusted_anchor = anchor + pinch_anchor_adjustment_; |
| float page_scale = active_tree->current_page_scale_factor(); |
| gfx::PointF previous_scale_anchor = |
| gfx::ScalePoint(adjusted_anchor, 1.f / page_scale); |
| active_tree->SetPageScaleOnActiveTree(page_scale * magnify_delta); |
| page_scale = active_tree->current_page_scale_factor(); |
| gfx::PointF new_scale_anchor = |
| gfx::ScalePoint(adjusted_anchor, 1.f / page_scale); |
| gfx::Vector2dF move = previous_scale_anchor - new_scale_anchor; |
| |
| // Scale back to viewport space since that's the coordinate space ScrollBy |
| // uses. |
| move.Scale(page_scale); |
| |
| // If clamping the inner viewport scroll offset causes a change, it should |
| // be accounted for from the intended move. |
| move -= InnerScrollLayer()->ClampScrollToMaxScrollOffset(); |
| |
| if (host_impl_->settings().invert_viewport_scroll_order) { |
| Pan(move); |
| } else { |
| gfx::Point viewport_point; |
| bool is_wheel_event = false; |
| bool affect_top_controls = false; |
| ScrollBy(move, viewport_point, is_wheel_event, affect_top_controls); |
| } |
| } |
| |
| void Viewport::PinchEnd() { |
| pinch_anchor_adjustment_ = gfx::Vector2d(); |
| pinch_zoom_active_ = false; |
| } |
| |
| gfx::Vector2dF Viewport::ScrollTopControls(const gfx::Vector2dF& delta) { |
| gfx::Vector2dF excess_delta = |
| host_impl_->top_controls_manager()->ScrollBy(delta); |
| |
| return delta - excess_delta; |
| } |
| |
| bool Viewport::ShouldTopControlsConsumeScroll( |
| const gfx::Vector2dF& scroll_delta) const { |
| // Always consume if it's in the direction to show the top controls. |
| if (scroll_delta.y() < 0) |
| return true; |
| |
| if (TotalScrollOffset().y() < MaxTotalScrollOffset().y()) |
| return true; |
| |
| return false; |
| } |
| |
| gfx::Vector2dF Viewport::AdjustOverscroll(const gfx::Vector2dF& delta) const { |
| // TODO(tdresser): Use a more rational epsilon. See crbug.com/510550 for |
| // details. |
| const float kEpsilon = 0.1f; |
| gfx::Vector2dF adjusted = delta; |
| |
| if (std::abs(adjusted.x()) < kEpsilon) |
| adjusted.set_x(0.0f); |
| if (std::abs(adjusted.y()) < kEpsilon) |
| adjusted.set_y(0.0f); |
| |
| return adjusted; |
| } |
| |
| gfx::ScrollOffset Viewport::MaxTotalScrollOffset() const { |
| gfx::ScrollOffset offset; |
| |
| offset += InnerScrollLayer()->MaxScrollOffset(); |
| |
| if (OuterScrollLayer()) |
| offset += OuterScrollLayer()->MaxScrollOffset(); |
| |
| return offset; |
| } |
| |
| gfx::ScrollOffset Viewport::TotalScrollOffset() const { |
| gfx::ScrollOffset offset; |
| |
| offset += InnerScrollLayer()->CurrentScrollOffset(); |
| |
| if (OuterScrollLayer()) |
| offset += OuterScrollLayer()->CurrentScrollOffset(); |
| |
| return offset; |
| } |
| |
| LayerImpl* Viewport::InnerScrollLayer() const { |
| return host_impl_->InnerViewportScrollLayer(); |
| } |
| |
| LayerImpl* Viewport::OuterScrollLayer() const { |
| return host_impl_->OuterViewportScrollLayer(); |
| } |
| |
| } // namespace cc |