1 files changed, 123 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/core/SkRasterClipStack.h b/gfx/skia/skia/src/core/SkRasterClipStack.h
new file mode 100644
index 0000000000..0d73122d4d
--- /dev/null
+++ b/gfx/skia/skia/src/core/SkRasterClipStack.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkRasterClipStack_DEFINED
+#define SkRasterClipStack_DEFINED
+
+#include "include/core/SkClipOp.h"
+#include "src/base/SkTBlockList.h"
+#include "src/core/SkRasterClip.h"
+#include "src/core/SkScan.h"
+
+class SkRasterClipStack : SkNoncopyable {
+public:
+    SkRasterClipStack(int width, int height)
+            : fRootBounds(SkIRect::MakeWH(width, height))
+            , fDisableAA(SkScan::PathRequiresTiling(fRootBounds)) {
+        fStack.emplace_back(SkRasterClip(fRootBounds));
+        SkASSERT(fStack.count() == 1);
+    }
+
+    void setNewSize(int w, int h) {
+        fRootBounds.setXYWH(0, 0, w, h);
+
+        SkASSERT(fStack.count() == 1);
+        Rec& rec = fStack.back();
+        SkASSERT(rec.fDeferredCount == 0);
+        rec.fRC.setRect(fRootBounds);
+    }
+
+    const SkRasterClip& rc() const { return fStack.back().fRC; }
+
+    void save() {
+        SkDEBUGCODE(fCounter += 1);
+        SkASSERT(fStack.back().fDeferredCount >= 0);
+        fStack.back().fDeferredCount += 1;
+    }
+
+    void restore() {
+        SkDEBUGCODE(fCounter -= 1);
+        SkASSERT(fCounter >= 0);
+
+        if (--fStack.back().fDeferredCount < 0) {
+            SkASSERT(fStack.back().fDeferredCount == -1);
+            SkASSERT(fStack.count() > 1);
+            fStack.pop_back();
+        }
+    }
+
+    void clipRect(const SkMatrix& ctm, const SkRect& rect, SkClipOp op, bool aa) {
+        this->writable_rc().op(rect, ctm, op, this->finalAA(aa));
+        this->validate();
+    }
+
+    void clipRRect(const SkMatrix& ctm, const SkRRect& rrect, SkClipOp op, bool aa) {
+        this->writable_rc().op(rrect, ctm, op, this->finalAA(aa));
+        this->validate();
+    }
+
+    void clipPath(const SkMatrix& ctm, const SkPath& path, SkClipOp op, bool aa) {
+        this->writable_rc().op(path, ctm, op, this->finalAA(aa));
+        this->validate();
+    }
+
+    void clipShader(sk_sp<SkShader> sh) {
+        this->writable_rc().op(std::move(sh));
+        this->validate();
+    }
+
+    void clipRegion(const SkRegion& rgn, SkClipOp op) {
+        this->writable_rc().op(rgn, op);
+        this->validate();
+    }
+
+    void replaceClip(const SkIRect& rect) {
+        SkIRect devRect = rect;
+        if (!devRect.intersect(fRootBounds)) {
+            this->writable_rc().setEmpty();
+        } else {
+            this->writable_rc().setRect(devRect);
+        }
+    }
+
+    void validate() const {
+#ifdef SK_DEBUG
+        const SkRasterClip& clip = this->rc();
+        if (fRootBounds.isEmpty()) {
+            SkASSERT(clip.isEmpty());
+        } else if (!clip.isEmpty()) {
+            SkASSERT(fRootBounds.contains(clip.getBounds()));
+        }
+#endif
+    }
+
+private:
+    struct Rec {
+        SkRasterClip fRC;
+        int          fDeferredCount; // 0 for a "normal" entry
+
+        Rec(const SkRasterClip& rc) : fRC(rc), fDeferredCount(0) {}
+    };
+
+    SkTBlockList<Rec, 16> fStack;
+    SkIRect fRootBounds;
+    bool fDisableAA;
+    SkDEBUGCODE(int fCounter = 0);
+
+    SkRasterClip& writable_rc() {
+        SkASSERT(fStack.back().fDeferredCount >= 0);
+        if (fStack.back().fDeferredCount > 0) {
+            fStack.back().fDeferredCount -= 1;
+            fStack.emplace_back(fStack.back().fRC);
+        }
+        return fStack.back().fRC;
+    }
+
+    bool finalAA(bool aa) const { return aa && !fDisableAA; }
+};
+
+#endif