1 files changed, 123 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/gpu/GrWindowRectangles.h b/gfx/skia/skia/src/gpu/GrWindowRectangles.h
new file mode 100644
index 0000000000..1b6bc4dfee
--- /dev/null
+++ b/gfx/skia/skia/src/gpu/GrWindowRectangles.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrWindowRectangles_DEFINED
+#define GrWindowRectangles_DEFINED
+
+#include "include/core/SkRect.h"
+#include "src/gpu/GrNonAtomicRef.h"
+
+class GrWindowRectangles {
+public:
+    constexpr static int kMaxWindows = 8;
+
+    GrWindowRectangles() : fCount(0) {}
+    GrWindowRectangles(const GrWindowRectangles& that) : fCount(0) { *this = that; }
+    ~GrWindowRectangles() { SkSafeUnref(this->rec()); }
+
+    GrWindowRectangles makeOffset(int dx, int dy) const;
+
+    bool empty() const { return !fCount; }
+    int count() const { return fCount; }
+    const SkIRect* data() const;
+
+    void reset();
+    GrWindowRectangles& operator=(const GrWindowRectangles&);
+
+    SkIRect& addWindow(const SkIRect& window) { return this->addWindow() = window; }
+    SkIRect& addWindow();
+
+    bool operator!=(const GrWindowRectangles& that) const { return !(*this == that); }
+    bool operator==(const GrWindowRectangles&) const;
+
+private:
+    constexpr static int kNumLocalWindows = 1;
+    struct Rec;
+
+    const Rec* rec() const { return fCount <= kNumLocalWindows ? nullptr : fRec; }
+
+    int fCount;
+    union {
+        SkIRect   fLocalWindows[kNumLocalWindows]; // If fCount <= kNumLocalWindows.
+        Rec*      fRec;                            // If fCount > kNumLocalWindows.
+    };
+};
+
+struct GrWindowRectangles::Rec : public GrNonAtomicRef<Rec> {
+    Rec(const SkIRect* windows, int numWindows) {
+        SkASSERT(numWindows < kMaxWindows);
+        memcpy(fData, windows, sizeof(SkIRect) * numWindows);
+    }
+    Rec() = default;
+
+    SkIRect fData[kMaxWindows];
+};
+
+inline const SkIRect* GrWindowRectangles::data() const {
+    return fCount <= kNumLocalWindows ? fLocalWindows : fRec->fData;
+}
+
+inline void GrWindowRectangles::reset() {
+    SkSafeUnref(this->rec());
+    fCount = 0;
+}
+
+inline GrWindowRectangles& GrWindowRectangles::operator=(const GrWindowRectangles& that) {
+    SkSafeUnref(this->rec());
+    fCount = that.fCount;
+    if (fCount <= kNumLocalWindows) {
+        memcpy(fLocalWindows, that.fLocalWindows, fCount * sizeof(SkIRect));
+    } else {
+        fRec = SkRef(that.fRec);
+    }
+    return *this;
+}
+
+inline GrWindowRectangles GrWindowRectangles::makeOffset(int dx, int dy) const {
+    if (!dx && !dy) {
+        return *this;
+    }
+    GrWindowRectangles result;
+    result.fCount = fCount;
+    SkIRect* windows;
+    if (result.fCount > kNumLocalWindows) {
+        result.fRec = new Rec();
+        windows = result.fRec->fData;
+    } else {
+        windows = result.fLocalWindows;
+    }
+    for (int i = 0; i < fCount; ++i) {
+        windows[i] = this->data()[i].makeOffset(dx, dy);
+    }
+    return result;
+}
+
+inline SkIRect& GrWindowRectangles::addWindow() {
+    SkASSERT(fCount < kMaxWindows);
+    if (fCount < kNumLocalWindows) {
+        return fLocalWindows[fCount++];
+    }
+    if (fCount == kNumLocalWindows) {
+        fRec = new Rec(fLocalWindows, kNumLocalWindows);
+    } else if (!fRec->unique()) { // Simple copy-on-write.
+        fRec->unref();
+        fRec = new Rec(fRec->fData, fCount);
+    }
+    return fRec->fData[fCount++];
+}
+
+inline bool GrWindowRectangles::operator==(const GrWindowRectangles& that) const {
+    if (fCount != that.fCount) {
+        return false;
+    }
+    if (fCount > kNumLocalWindows && fRec == that.fRec) {
+        return true;
+    }
+    return !fCount || !memcmp(this->data(), that.data(), sizeof(SkIRect) * fCount);
+}
+
+#endif