1 files changed, 45 insertions, 6 deletions

diff --git a/experimental/sksg/effects/SkSGTransform.cpp b/experimental/sksg/effects/SkSGTransform.cpp
index dc31623db2..1ea1e619a8 100644
--- a/experimental/sksg/effects/SkSGTransform.cpp
+++ b/experimental/sksg/effects/SkSGTransform.cpp
@@ -11,21 +11,60 @@
 
 namespace sksg {
 
-Transform::Transform(sk_sp<RenderNode> child, const SkMatrix& matrix)
+Matrix::Matrix(const SkMatrix& m, sk_sp<Matrix> parent)
+    : fParent(std::move(parent))
+    , fLocalMatrix(m) {
+    if (fParent) {
+        fParent->addInvalReceiver(this);
+    }
+}
+
+Matrix::~Matrix() {
+    if (fParent) {
+        fParent->removeInvalReceiver(this);
+    }
+}
+
+Node::RevalidationResult Matrix::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
+    fTotalMatrix = fLocalMatrix;
+
+    if (fParent) {
+        fParent->revalidate(ic, ctm);
+        fTotalMatrix.postConcat(fParent->getTotalMatrix());
+    }
+
+    // A free-floating matrix contributes no damage.
+    return { SkRect::MakeEmpty(), Damage::kBlockSelf };
+}
+
+Transform::Transform(sk_sp<RenderNode> child, sk_sp<Matrix> matrix)
     : INHERITED(std::move(child))
-    , fMatrix(matrix) {}
+    , fMatrix(std::move(matrix)) {
+    fMatrix->addInvalReceiver(this);
+}
+
+Transform::~Transform() {
+    fMatrix->removeInvalReceiver(this);
+}
 
 void Transform::onRender(SkCanvas* canvas) const {
-    SkAutoCanvasRestore acr(canvas, !fMatrix.isIdentity());
-    canvas->concat(fMatrix);
+    const auto& m = fMatrix->getTotalMatrix();
+    SkAutoCanvasRestore acr(canvas, !m.isIdentity());
+    canvas->concat(m);
     this->INHERITED::onRender(canvas);
 }
 
 Node::RevalidationResult Transform::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
     SkASSERT(this->hasInval());
 
-    auto result = this->INHERITED::onRevalidate(ic, SkMatrix::Concat(ctm, fMatrix));
-    fMatrix.mapRect(&result.fBounds);
+    // We don't care about matrix reval results, but we do care whether it was invalidated.
+    const auto localDamage = fMatrix->hasInval() ? Damage::kForceSelf : Damage::kDefault;
+    fMatrix->revalidate(ic, ctm);
+
+    const auto& m = fMatrix->getTotalMatrix();
+    auto result = this->INHERITED::onRevalidate(ic, SkMatrix::Concat(ctm, m));
+    m.mapRect(&result.fBounds);
+    result.fDamage = localDamage;
 
     return result;
 }