diff options
| -rw-r--r-- | components/script/script_task.rs | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/components/script/script_task.rs b/components/script/script_task.rs index 02046df717e..fa427db6ff1 100644 --- a/components/script/script_task.rs +++ b/components/script/script_task.rs @@ -1669,12 +1669,21 @@ impl ScriptTask { } fn scroll_fragment_point(&self, pipeline_id: PipelineId, element: &Element) { - let rect = element.upcast::<Node>().get_bounding_content_box(); - let point = Point2D::new(rect.origin.x.to_f32_px(), rect.origin.y.to_f32_px()); - // FIXME(#2003, pcwalton): This is pretty bogus when multiple layers are involved. + // FIXME(#8275, pcwalton): This is pretty bogus when multiple layers are involved. // Really what needs to happen is that this needs to go through layout to ask which // layer the element belongs to, and have it send the scroll message to the // compositor. + let rect = element.upcast::<Node>().get_bounding_content_box(); + + // In order to align with element edges, we snap to unscaled pixel boundaries, since the + // paint task currently does the same for drawing elements. This is important for pages + // that require pixel perfect scroll positioning for proper display (like Acid2). Since we + // don't have the device pixel ratio here, this might not be accurate, but should work as + // long as the ratio is a whole number. Once #8275 is fixed this should actually take into + // account the real device pixel ratio. + let point = Point2D::new(rect.origin.x.to_nearest_px() as f32, + rect.origin.y.to_nearest_px() as f32); + self.compositor.borrow_mut().send(ScriptToCompositorMsg::ScrollFragmentPoint( pipeline_id, LayerId::null(), point, false)).unwrap(); } |