Initial scene graph (SkSG)
Sketching a thin (as in close-to-skia-semantics) scene graph API, focused on
external animation, inval tracking and minimal repaint.
Only a few concrete classes/features so far:
* Rect/Color/Transform/Group
* basic inval tracking
* a trivial animated sample with inval visualization
Pretty much everything (especially naming) is volatile, so treat accordingly.
The interesting bits to review are likely in Node.{h,cpp} for inval and
SampleSGInval.cpp for usage.
Initial class hierarchy:
* Node: invalidation/ancestors tracking
|
-- * RenderNode: onRender(SkCanvas)
| |
| -- * Draw (concrete): rendering a [geometry, paint] tuple
| |
| -- * Group (concrete): grouping multiple RenderNodes
| |
| -- * EffectNode: single-descendant effect wrapper
| |
| -- * Transform (concrete): transform effect
|
-- * PaintNode: onMakePaint()
| |
| -- * Color (concrete): SkColor paint wrapper
|
-- * GeometryNode: onComputeBounds(), onDraw(SkCanvas, SkPaint)
|
-- * Rect (concrete): SkRect wrapper
TBR=
Change-Id: Iacf9b773c181a7582ecd31ee968562f179d1aa1b
Reviewed-on: https://skia-review.googlesource.com/85502
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/experimental/sksg/SkSGNode.cpp b/experimental/sksg/SkSGNode.cpp
new file mode 100644
index 0000000..3b404ed
--- /dev/null
+++ b/experimental/sksg/SkSGNode.cpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkSGNode.h"
+
+namespace sksg {
+
+class Node::ScopedFlag {
+public:
+ ScopedFlag(Node* node, uint32_t flag)
+ : fNode(node)
+ , fFlag(flag) {
+ SkASSERT(!(fNode->fFlags & fFlag));
+ fNode->fFlags |= fFlag;
+ }
+ ~ScopedFlag() {
+ fNode->fFlags &= ~fFlag;;
+ }
+
+private:
+ Node* fNode;
+ uint32_t fFlag;
+};
+
+#define TRAVERSAL_GUARD \
+ if (this->fFlags & kInTraversal_Flag) { \
+ return; \
+ } \
+ ScopedFlag traversal_guard(this, kInTraversal_Flag);
+
+Node::Node()
+ : fInvalReceiver(nullptr)
+ , fFlags(kInvalidated_Flag) {}
+
+Node::~Node() {
+ if (fFlags & kReceiverArray_Flag) {
+ SkASSERT(fInvalReceiverArray->isEmpty());
+ delete fInvalReceiverArray;
+ } else {
+ SkASSERT(!fInvalReceiver);
+ }
+}
+
+void Node::addInvalReceiver(Node* receiver) {
+ if (!(fFlags & kReceiverArray_Flag)) {
+ if (!fInvalReceiver) {
+ fInvalReceiver = receiver;
+ return;
+ }
+
+ auto receivers = new SkTDArray<Node*>();
+ receivers->setReserve(2);
+ receivers->push(fInvalReceiver);
+
+ fInvalReceiverArray = receivers;
+ fFlags |= kReceiverArray_Flag;
+ }
+
+ // No duplicate receivers.
+ SkASSERT(fInvalReceiverArray->find(receiver) < 0);
+
+ fInvalReceiverArray->push(receiver);
+}
+
+void Node::removeInvalReceiver(Node* receiver) {
+ if (!(fFlags & kReceiverArray_Flag)) {
+ SkASSERT(fInvalReceiver == receiver);
+ fInvalReceiver = nullptr;
+ return;
+ }
+
+ const auto idx = fInvalReceiverArray->find(receiver);
+ SkASSERT(idx >= 0);
+ fInvalReceiverArray->remove(idx);
+}
+
+template <typename Func>
+void Node::forEachInvalReceiver(Func&& func) const {
+ if (fFlags & kReceiverArray_Flag) {
+ for (const auto& parent : *fInvalReceiverArray) {
+ func(parent);
+ }
+ return;
+ }
+
+ if (fInvalReceiver) {
+ func(fInvalReceiver);
+ }
+}
+
+void Node::invalidate() {
+ TRAVERSAL_GUARD
+
+ if (this->isInvalidated()) {
+ return;
+ }
+
+ fFlags |= kInvalidated_Flag;
+ forEachInvalReceiver([&](Node* receiver) {
+ receiver->invalidate();
+ });
+}
+
+void Node::revalidate(InvalidationController* ic, const SkMatrix& ctm) {
+ TRAVERSAL_GUARD
+
+ if (this->isInvalidated()) {
+ this->onRevalidate(ic, ctm);
+ fFlags &= ~kInvalidated_Flag;
+ }
+}
+
+} // namespace sksg