Auto merge of #13820 - mrobinson:remove-nesting, r=glennw

Remove the concept of nested stacking contexts from display list builder

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- [ ] These changes fix #__ (github issue number if applicable).

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With the removal of the legacy rendering path, we don't need to worry
about nested stacking contexts. This change just pushes the
complication to the WebRender conversion step, but a later change will
remove the concept from WebRender as well.

This also helps to prepare for the introduction of ids for particular
scrolling regions, an integral part of multiple ScrollLayers per block.

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This commit is contained in:
bors-servo 2016-10-19 12:54:40 -05:00 committed by GitHub
commit e667e62f0c
4 changed files with 105 additions and 109 deletions

View file

@ -9,7 +9,7 @@
use app_units::Au;
use azure::azure_hl::Color;
use euclid::{Point2D, Rect, Size2D};
use euclid::{Matrix4D, Point2D, Rect, Size2D};
use gfx::display_list::{BorderRadii, BoxShadowClipMode, ClippingRegion};
use gfx::display_list::{DisplayItem, DisplayList, DisplayListTraversal};
use gfx::display_list::{GradientStop, StackingContext, StackingContextType};
@ -266,7 +266,7 @@ impl WebRenderStackingContextConverter for StackingContext {
let stacking_context = &stacking_context_item.stacking_context;
debug_assert!(stacking_context.context_type == StackingContextType::Real);
let scroll_layer_id_for_children = if self.scrolls_overflow_area {
let scroll_layer_id_for_children = if self.overflow_scroll_id.is_some() {
scroll_layer_id
} else {
None
@ -294,7 +294,7 @@ impl WebRenderStackingContextConverter for StackingContext {
api: &mut webrender_traits::RenderApi,
pipeline_id: webrender_traits::PipelineId,
epoch: webrender_traits::Epoch,
mut scroll_layer_id: Option<webrender_traits::ScrollLayerId>,
scroll_layer_id: Option<webrender_traits::ScrollLayerId>,
mut scroll_policy: ScrollPolicy,
frame_builder: &mut WebRenderFrameBuilder)
-> webrender_traits::StackingContextId {
@ -309,12 +309,18 @@ impl WebRenderStackingContextConverter for StackingContext {
let webrender_stacking_context_id = self.id.convert_to_webrender();
let outer_overflow = if self.overflow_scroll_id.is_none() {
self.overflow.to_rectf()
} else {
Rect::new(Point2D::zero(), self.bounds.size).to_rectf()
};
let mut sc =
webrender_traits::StackingContext::new(webrender_stacking_context_id,
scroll_layer_id,
webrender_scroll_policy,
self.bounds.to_rectf(),
self.overflow.to_rectf(),
outer_overflow,
self.z_index,
&self.transform,
&self.perspective,
@ -325,19 +331,49 @@ impl WebRenderStackingContextConverter for StackingContext {
let mut builder = webrender_traits::DisplayListBuilder::new();
if self.scrolls_overflow_area {
scroll_layer_id = Some(frame_builder.next_scroll_layer_id());
if let Some(inner_stacking_context_id) = self.overflow_scroll_id {
let inner_webrender_stacking_context_id =
inner_stacking_context_id.convert_to_webrender();
let mut inner_sc =
webrender_traits::StackingContext::new(inner_webrender_stacking_context_id,
Some(frame_builder.next_scroll_layer_id()),
webrender_scroll_policy,
self.overflow.to_rectf(),
self.overflow.to_rectf(),
self.z_index,
&Matrix4D::identity(),
&Matrix4D::identity(),
false,
webrender_traits::MixBlendMode::Normal,
Vec::new(),
&mut frame_builder.auxiliary_lists_builder);
let mut inner_builder = webrender_traits::DisplayListBuilder::new();
self.convert_children_to_webrender(traversal,
api,
pipeline_id,
epoch,
None,
scroll_policy,
&mut inner_builder,
frame_builder,
false);
frame_builder.add_display_list(api, inner_builder.finalize(), &mut inner_sc);
let new_id = frame_builder.add_stacking_context(api, pipeline_id, inner_sc);
builder.push_stacking_context(new_id);
} else {
self.convert_children_to_webrender(traversal,
api,
pipeline_id,
epoch,
scroll_layer_id,
scroll_policy,
&mut builder,
frame_builder,
false);
}
self.convert_children_to_webrender(traversal,
api,
pipeline_id,
epoch,
scroll_layer_id,
scroll_policy,
&mut builder,
frame_builder,
false);
frame_builder.add_display_list(api, builder.finalize(), &mut sc);
frame_builder.add_stacking_context(api, pipeline_id, sc)
}