Changes between Version 1 and Version 2 of FiveYearPlan

Timestamp:

Mar 12, 2015, 2:27:12 PM (10 years ago)

Author:

bfulgham@webkit.org

Comment:

--

FiveYearPlan

@@ -13 +13 @@
 
 == Render Tree Refcounting ==
-Goal is to manage repaint complexity by moving to a refcount model.
+Goal is to manage repaint complexity by moving to a refcount model for the Render Tree. The existing tree of nodes with back-pointers is very difficult to reason about.
+* Possibly treat render tree as immutable after layout. Use this read-only tree to answer questions about current layout.
 * Downside:
-   1. Potential for recycles.
+   1. Potential for ref cycles.
    1. Slightly larger memory use (additional count)
+   1. Potential cost of copying the trees.
+* Benefits:
+   1. Allow layout and painting logic to be split, perhaps run on separate threads.
+   1. Allow us to get rid of some back pointers.
+   1. Allow hit testing or other "read only" operations to be done on the read-only tree.
+   1. Allow web code to query geometry and other questions '''without''' triggering layout.
 
 == Painting: Display Lists ==
@@ -33 +40 @@
 * Downstream
 * Incremental
+
+== Threading ==
+* Text measurement