diff options
Diffstat (limited to 'gfx/wr/webrender/src/spatial_tree.rs')
| -rw-r--r-- | gfx/wr/webrender/src/spatial_tree.rs | 122 |
1 files changed, 97 insertions, 25 deletions
diff --git a/gfx/wr/webrender/src/spatial_tree.rs b/gfx/wr/webrender/src/spatial_tree.rs index 0aa6bb5296..94e934ca53 100644 --- a/gfx/wr/webrender/src/spatial_tree.rs +++ b/gfx/wr/webrender/src/spatial_tree.rs @@ -335,9 +335,11 @@ impl SceneSpatialTree { pub fn find_scroll_root( &self, spatial_node_index: SpatialNodeIndex, + allow_sticky_frames: bool, ) -> SpatialNodeIndex { let mut real_scroll_root = self.root_reference_frame_index; let mut outermost_scroll_root = self.root_reference_frame_index; + let mut current_scroll_root_is_sticky = false; let mut node_index = spatial_node_index; while node_index != self.root_reference_frame_index { @@ -354,10 +356,21 @@ impl SceneSpatialTree { // we have encountered, as they may end up with a non-axis-aligned transform. real_scroll_root = self.root_reference_frame_index; outermost_scroll_root = self.root_reference_frame_index; + current_scroll_root_is_sticky = false; } } } - SpatialNodeType::StickyFrame(..) => {} + SpatialNodeType::StickyFrame(..) => { + // Though not a scroll frame, we optionally treat sticky frames as scroll roots + // to ensure they are given a separate picture cache slice. + if allow_sticky_frames { + outermost_scroll_root = node_index; + real_scroll_root = node_index; + // Set this true so that we don't select an ancestor scroll frame as the scroll root + // on a subsequent iteration. + current_scroll_root_is_sticky = true; + } + } SpatialNodeType::ScrollFrame(ref info) => { match info.frame_kind { ScrollFrameKind::PipelineRoot { is_root_pipeline } => { @@ -371,24 +384,29 @@ impl SceneSpatialTree { // later on, even if it's not actually scrollable. outermost_scroll_root = node_index; - // If the scroll root has no scrollable area, we don't want to - // consider it. This helps pages that have a nested scroll root - // within a redundant scroll root to avoid selecting the wrong - // reference spatial node for a picture cache. - if info.scrollable_size.width > MIN_SCROLLABLE_AMOUNT || - info.scrollable_size.height > MIN_SCROLLABLE_AMOUNT { - // Since we are skipping redundant scroll roots, we may end up - // selecting inner scroll roots that are very small. There is - // no performance benefit to creating a slice for these roots, - // as they are cheap to rasterize. The size comparison is in - // local-space, but makes for a reasonable estimate. The value - // is arbitrary, but is generally small enough to ignore things - // like scroll roots around text input elements. - if info.viewport_rect.width() > MIN_SCROLL_ROOT_SIZE && - info.viewport_rect.height() > MIN_SCROLL_ROOT_SIZE { - // If we've found a root that is scrollable, and a reasonable - // size, select that as the current root for this node - real_scroll_root = node_index; + // If the previously identified scroll root is sticky then we don't + // want to choose an ancestor scroll root, as we want the sticky item + // to have its own picture cache slice. + if !current_scroll_root_is_sticky { + // If the scroll root has no scrollable area, we don't want to + // consider it. This helps pages that have a nested scroll root + // within a redundant scroll root to avoid selecting the wrong + // reference spatial node for a picture cache. + if info.scrollable_size.width > MIN_SCROLLABLE_AMOUNT || + info.scrollable_size.height > MIN_SCROLLABLE_AMOUNT { + // Since we are skipping redundant scroll roots, we may end up + // selecting inner scroll roots that are very small. There is + // no performance benefit to creating a slice for these roots, + // as they are cheap to rasterize. The size comparison is in + // local-space, but makes for a reasonable estimate. The value + // is arbitrary, but is generally small enough to ignore things + // like scroll roots around text input elements. + if info.viewport_rect.width() > MIN_SCROLL_ROOT_SIZE && + info.viewport_rect.height() > MIN_SCROLL_ROOT_SIZE { + // If we've found a root that is scrollable, and a reasonable + // size, select that as the current root for this node + real_scroll_root = node_index; + } } } } @@ -1732,7 +1750,7 @@ fn test_find_scroll_root_simple() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 1), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(scroll), scroll); + assert_eq!(st.find_scroll_root(scroll, true), scroll); } /// Tests that we select the root scroll frame rather than the subframe if both are scrollable. @@ -1781,7 +1799,7 @@ fn test_find_scroll_root_sub_scroll_frame() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 2), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(sub_scroll), root_scroll); + assert_eq!(st.find_scroll_root(sub_scroll, true), root_scroll); } /// Tests that we select the sub scroll frame when the root scroll frame is not scrollable. @@ -1830,7 +1848,7 @@ fn test_find_scroll_root_not_scrollable() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 2), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(sub_scroll), sub_scroll); + assert_eq!(st.find_scroll_root(sub_scroll, true), sub_scroll); } /// Tests that we select the sub scroll frame when the root scroll frame is too small. @@ -1879,7 +1897,7 @@ fn test_find_scroll_root_too_small() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 2), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(sub_scroll), sub_scroll); + assert_eq!(st.find_scroll_root(sub_scroll, true), sub_scroll); } /// Tests that we select the root scroll node, even if it is not scrollable, @@ -1941,7 +1959,7 @@ fn test_find_scroll_root_perspective() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 3), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(sub_scroll), root_scroll); + assert_eq!(st.find_scroll_root(sub_scroll, true), root_scroll); } /// Tests that encountering a 2D scale or translation transform does not prevent @@ -2005,7 +2023,61 @@ fn test_find_scroll_root_2d_scale() { SpatialNodeUid::external(SpatialTreeItemKey::new(0, 3), PipelineId::dummy(), pid), ); - assert_eq!(st.find_scroll_root(sub_scroll), sub_scroll); + assert_eq!(st.find_scroll_root(sub_scroll, true), sub_scroll); +} + +/// Tests that a sticky spatial node is chosen as the scroll root rather than +/// its parent scroll frame +#[test] +fn test_find_scroll_root_sticky() { + let mut st = SceneSpatialTree::new(); + let pid = PipelineInstanceId::new(0); + + let root = st.add_reference_frame( + st.root_reference_frame_index(), + TransformStyle::Flat, + PropertyBinding::Value(LayoutTransform::identity()), + ReferenceFrameKind::Transform { + is_2d_scale_translation: true, + should_snap: true, + paired_with_perspective: false, + }, + LayoutVector2D::new(0.0, 0.0), + PipelineId::dummy(), + SpatialNodeUid::external(SpatialTreeItemKey::new(0, 0), PipelineId::dummy(), pid), + ); + + let scroll = st.add_scroll_frame( + root, + ExternalScrollId(1, PipelineId::dummy()), + PipelineId::dummy(), + &LayoutRect::from_size(LayoutSize::new(400.0, 400.0)), + &LayoutSize::new(400.0, 800.0), + ScrollFrameKind::Explicit, + LayoutVector2D::new(0.0, 0.0), + APZScrollGeneration::default(), + HasScrollLinkedEffect::No, + SpatialNodeUid::external(SpatialTreeItemKey::new(0, 1), PipelineId::dummy(), pid), + ); + + let sticky = st.add_sticky_frame( + scroll, + StickyFrameInfo { + frame_rect: LayoutRect::from_size(LayoutSize::new(400.0, 100.0)), + margins: euclid::SideOffsets2D::new(Some(0.0), None, None, None), + vertical_offset_bounds: api::StickyOffsetBounds::new(0.0, 0.0), + horizontal_offset_bounds: api::StickyOffsetBounds::new(0.0, 0.0), + previously_applied_offset: LayoutVector2D::zero(), + current_offset: LayoutVector2D::zero(), + transform: None + }, + PipelineId::dummy(), + SpatialTreeItemKey::new(0, 2), + pid, + ); + + assert_eq!(st.find_scroll_root(sticky, true), sticky); + assert_eq!(st.find_scroll_root(sticky, false), scroll); } #[test] |