Encapsulate GrReducedClip result in class members

Updates GrReducedClip to store its result in class members instead of
various pointer arguments. This helps clean up calling code and will
make it easier to reduce the clip higher in the stack.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2222873002

Review-Url: https://codereview.chromium.org/2222873002

1 files changed, 44 insertions, 24 deletions

diff --git a/src/gpu/GrReducedClip.h b/src/gpu/GrReducedClip.h
index 780f6f1ff5..07e06694a1 100644
--- a/src/gpu/GrReducedClip.h
+++ b/src/gpu/GrReducedClip.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 Google Inc.
+ * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
@@ -11,37 +11,57 @@
 #include "SkClipStack.h"
 #include "SkTLList.h"
 
+/**
+ * This class takes a clip stack and produces a reduced set of elements that are equivalent to
+ * applying that full stack within a specified query rectangle.
+ */
 class SK_API GrReducedClip {
 public:
+    GrReducedClip(const SkClipStack& stack, const SkRect& queryBounds);
+
+    /**
+     * Uniquely identifies this reduced clip.
+     */
+    int32_t genID() const { return fGenID; }
+
+    /**
+     * Bounding box within which the reduced clip is valid. The caller must not draw any pixels
+     * outside this box.
+     */
+    const SkIRect& iBounds() const { return fIBounds; }
+    int left() const { return this->iBounds().left(); }
+    int top() const { return this->iBounds().top(); }
+    int width() const { return this->iBounds().width(); }
+    int height() const { return this->iBounds().height(); }
+
     typedef SkTLList<SkClipStack::Element, 16> ElementList;
 
-    enum InitialState {
-        kAllIn_InitialState,
-        kAllOut_InitialState,
+    /**
+     * Populated with a minimal list of elements that implement the clip.
+     */
+    const ElementList& elements() const { return fElements; }
+
+    /**
+     * Indicates whether antialiasing is required to process any of the clip elements.
+     */
+    bool requiresAA() const { return fRequiresAA; }
+
+    enum class InitialState : bool {
+        kAllIn,
+        kAllOut
     };
 
     /**
-     * This function produces a reduced set of SkClipStack::Elements that are equivalent to applying
-     * a full clip stack within a specified query rectangle.
-     *
-     * @param stack          the clip stack to reduce.
-     * @param queryBounds    bounding box of geometry the stack will clip.
-     * @param result         populated with a minimal list of elements that implement the clip
-     *                       within the provided query bounds.
-     * @param resultGenID    uniquely identifies the resulting reduced clip.
-     * @param clipIBounds    bounding box within which the reduced clip is valid. The caller must
-     *                       not draw any pixels outside this box. NOTE: this box may be undefined
-     *                       if no pixels are valid (e.g. empty result, "all out" initial state.)
-     * @param requiresAA     indicates whether anti-aliasing is required to process any of the
-     *                       elements in the element list result. Undefined if the result is empty.
-     * @return the initial clip state within clipIBounds ("all in" or "all out").
+     * The initial state of the clip within iBounds().
      */
-    static InitialState ReduceClipStack(const SkClipStack& stack,
-                                        const SkRect& queryBounds,
-                                        ElementList* result,
-                                        int32_t* resultGenID,
-                                        SkIRect* clipIBounds,
-                                        bool* requiresAA);
+    InitialState initialState() const { return fInitialState; }
+
+private:
+    int32_t        fGenID;
+    SkIRect        fIBounds;
+    ElementList    fElements;
+    bool           fRequiresAA;
+    InitialState   fInitialState;
 };
 
 #endif