[sksg] Refine invalidation logic

We need to discriminate between nodes whose bounds updates contribute to the dirty
region, and nodes whose bounds changes do not.

E.g. animated shape in a group: the animated shape node bounds should yield damage,
but the ancestor group bounds should not.

To accomplish this, we refine the invalidation state:

  1) self invalidation == the node itself was invalidated, and its bounds updates
     yield damage.
  2) descendant invalidation == the node has some (self-)invalidated descendant,
     but its own bounds are not contributing damage.

Also:

  * hoist the bounding box invalidation logic into the base class (Node::revalidate)
    and update to respect the states described above.
  * remove (now-redundant) GeometryNode bbox logic.
  * update revalidation methods to return the node bbox instead of void

TBR=
Change-Id: I8023d1793fb501c945a53f2dc2d2983e5b620ade
Reviewed-on: https://skia-review.googlesource.com/90581
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>

1 files changed, 15 insertions, 11 deletions

diff --git a/experimental/sksg/SkSGPaintNode.cpp b/experimental/sksg/SkSGPaintNode.cpp
index 2b7a31fbad..fbdfae5d69 100644
--- a/experimental/sksg/SkSGPaintNode.cpp
+++ b/experimental/sksg/SkSGPaintNode.cpp
@@ -12,23 +12,27 @@ namespace sksg {
 PaintNode::PaintNode() {}
 
 const SkPaint& PaintNode::makePaint() {
-    SkASSERT(!this->isInvalidated());
+    SkASSERT(!this->hasInval());
 
     return fPaint;
 }
 
-void PaintNode::onRevalidate(InvalidationController*, const SkMatrix&) {
-    SkASSERT(this->isInvalidated());
+SkRect PaintNode::onRevalidate(InvalidationController*, const SkMatrix&) {
+    SkASSERT(this->hasInval());
 
-    fPaint.reset();
-    fPaint.setAntiAlias(fAntiAlias);
-    fPaint.setStyle(fStyle);
-    fPaint.setStrokeWidth(fStrokeWidth);
-    fPaint.setStrokeMiter(fStrokeMiter);
-    fPaint.setStrokeJoin(fStrokeJoin);
-    fPaint.setStrokeCap(fStrokeCap);
+    if (this->hasSelfInval()) {
+        fPaint.reset();
+        fPaint.setAntiAlias(fAntiAlias);
+        fPaint.setStyle(fStyle);
+        fPaint.setStrokeWidth(fStrokeWidth);
+        fPaint.setStrokeMiter(fStrokeMiter);
+        fPaint.setStrokeJoin(fStrokeJoin);
+        fPaint.setStrokeCap(fStrokeCap);
 
-    this->onApplyToPaint(&fPaint);
+        this->onApplyToPaint(&fPaint);
+    }
+
+    return SkRect::MakeEmpty();
 }
 
 } // namespace sksg