1 files changed, 156 insertions, 0 deletions
diff --git a/image/ImageRegion.h b/image/ImageRegion.h
new file mode 100644
index 0000000000..0acc6e007b
--- /dev/null
+++ b/image/ImageRegion.h
@@ -0,0 +1,156 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_image_ImageRegion_h
+#define mozilla_image_ImageRegion_h
+
+#include "gfxMatrix.h"
+#include "gfxPoint.h"
+#include "gfxRect.h"
+#include "gfxTypes.h"
+#include "mozilla/gfx/Matrix.h"
+#include "mozilla/gfx/Types.h"
+#include "nsSize.h"
+
+namespace mozilla {
+namespace image {
+
+/**
+ * An axis-aligned rectangle in tiled image space, with an optional sampling
+ * restriction rect. The drawing code ensures that if a sampling restriction
+ * rect is present, any pixels sampled during the drawing process are found
+ * within that rect.
+ *
+ * The sampling restriction rect exists primarily for callers which perform
+ * pixel snapping. Other callers should generally use one of the Create()
+ * overloads.
+ */
+class ImageRegion {
+  typedef mozilla::gfx::ExtendMode ExtendMode;
+
+ public:
+  static ImageRegion Empty() {
+    return ImageRegion(gfxRect(), ExtendMode::CLAMP);
+  }
+
+  static ImageRegion Create(const gfxRect& aRect,
+                            ExtendMode aExtendMode = ExtendMode::CLAMP) {
+    return ImageRegion(aRect, aExtendMode);
+  }
+
+  static ImageRegion Create(const gfxSize& aSize,
+                            ExtendMode aExtendMode = ExtendMode::CLAMP) {
+    return ImageRegion(gfxRect(0, 0, aSize.width, aSize.height), aExtendMode);
+  }
+
+  static ImageRegion Create(const nsIntSize& aSize,
+                            ExtendMode aExtendMode = ExtendMode::CLAMP) {
+    return ImageRegion(gfxRect(0, 0, aSize.width, aSize.height), aExtendMode);
+  }
+
+  static ImageRegion CreateWithSamplingRestriction(
+      const gfxRect& aRect, const gfxRect& aRestriction,
+      ExtendMode aExtendMode = ExtendMode::CLAMP) {
+    return ImageRegion(aRect, aRestriction, aExtendMode);
+  }
+
+  bool IsRestricted() const { return mIsRestricted; }
+  const gfxRect& Rect() const { return mRect; }
+
+  const gfxRect& Restriction() const {
+    MOZ_ASSERT(mIsRestricted);
+    return mRestriction;
+  }
+
+  bool RestrictionContains(const gfxRect& aRect) const {
+    if (!mIsRestricted) {
+      return true;
+    }
+    return mRestriction.Contains(aRect);
+  }
+
+  ImageRegion Intersect(const gfxRect& aRect) const {
+    if (mIsRestricted) {
+      return CreateWithSamplingRestriction(aRect.Intersect(mRect),
+                                           aRect.Intersect(mRestriction));
+    }
+    return Create(aRect.Intersect(mRect));
+  }
+
+  gfxRect IntersectAndRestrict(const gfxRect& aRect) const {
+    gfxRect intersection = mRect.Intersect(aRect);
+    if (mIsRestricted) {
+      intersection = mRestriction.Intersect(intersection);
+    }
+    return intersection;
+  }
+
+  void MoveBy(gfxFloat dx, gfxFloat dy) {
+    mRect.MoveBy(dx, dy);
+    if (mIsRestricted) {
+      mRestriction.MoveBy(dx, dy);
+    }
+  }
+
+  void Scale(gfxFloat sx, gfxFloat sy) {
+    mRect.Scale(sx, sy);
+    if (mIsRestricted) {
+      mRestriction.Scale(sx, sy);
+    }
+  }
+
+  void TransformBy(const gfxMatrix& aMatrix) {
+    mRect = aMatrix.TransformRect(mRect);
+    if (mIsRestricted) {
+      mRestriction = aMatrix.TransformRect(mRestriction);
+    }
+  }
+
+  void TransformBoundsBy(const gfxMatrix& aMatrix) {
+    mRect = aMatrix.TransformBounds(mRect);
+    if (mIsRestricted) {
+      mRestriction = aMatrix.TransformBounds(mRestriction);
+    }
+  }
+
+  ImageRegion operator-(const gfxPoint& aPt) const {
+    if (mIsRestricted) {
+      return CreateWithSamplingRestriction(mRect - aPt, mRestriction - aPt);
+    }
+    return Create(mRect - aPt);
+  }
+
+  ImageRegion operator+(const gfxPoint& aPt) const {
+    if (mIsRestricted) {
+      return CreateWithSamplingRestriction(mRect + aPt, mRestriction + aPt);
+    }
+    return Create(mRect + aPt);
+  }
+
+  gfx::ExtendMode GetExtendMode() const { return mExtendMode; }
+
+  /* ImageRegion() : mIsRestricted(false) { } */
+
+ private:
+  explicit ImageRegion(const gfxRect& aRect, ExtendMode aExtendMode)
+      : mRect(aRect), mExtendMode(aExtendMode), mIsRestricted(false) {}
+
+  ImageRegion(const gfxRect& aRect, const gfxRect& aRestriction,
+              ExtendMode aExtendMode)
+      : mRect(aRect),
+        mRestriction(aRestriction),
+        mExtendMode(aExtendMode),
+        mIsRestricted(true) {}
+
+  gfxRect mRect;
+  gfxRect mRestriction;
+  ExtendMode mExtendMode;
+  bool mIsRestricted;
+};
+
+}  // namespace image
+}  // namespace mozilla
+
+#endif  // mozilla_image_ImageRegion_h