Avoid possible O(n) stack space use by skqsort.

https://codereview.appspot.com/7222043/


git-svn-id: http://skia.googlecode.com/svn/trunk@7470 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 22 insertions, 13 deletions

diff --git a/src/core/SkRTree.h b/src/core/SkRTree.h
index 139cc61b76..0a536677cd 100644
--- a/src/core/SkRTree.h
+++ b/src/core/SkRTree.h
@@ -119,19 +119,28 @@ private:
     typedef int32_t SkIRect::*SortSide;
 
     // Helper for sorting our children arrays by sides of their rects
-    static bool RectLessThan(SortSide const& side, const Branch lhs, const Branch rhs) {
-        return lhs.fBounds.*side < rhs.fBounds.*side;
-    }
-
-    static bool RectLessX(int&, const Branch lhs, const Branch rhs) {
-        return ((lhs.fBounds.fRight - lhs.fBounds.fLeft) >> 1) <
-               ((rhs.fBounds.fRight - lhs.fBounds.fLeft) >> 1);
-    }
-
-    static bool RectLessY(int&, const Branch lhs, const Branch rhs) {
-        return ((lhs.fBounds.fBottom - lhs.fBounds.fTop) >> 1) <
-               ((rhs.fBounds.fBottom - lhs.fBounds.fTop) >> 1);
-    }
+    struct RectLessThan {
+        RectLessThan(SkRTree::SortSide side) : fSide(side) { }
+        bool operator()(const SkRTree::Branch lhs, const SkRTree::Branch rhs) const {
+            return lhs.fBounds.*fSide < rhs.fBounds.*fSide;
+        }
+    private:
+        const SkRTree::SortSide fSide;
+    };
+
+    struct RectLessX {
+        bool operator()(const SkRTree::Branch lhs, const SkRTree::Branch rhs) {
+            return ((lhs.fBounds.fRight - lhs.fBounds.fLeft) >> 1) <
+                   ((rhs.fBounds.fRight - lhs.fBounds.fLeft) >> 1);
+        }
+    };
+
+    struct RectLessY {
+        bool operator()(const SkRTree::Branch lhs, const SkRTree::Branch rhs) {
+            return ((lhs.fBounds.fBottom - lhs.fBounds.fTop) >> 1) <
+                   ((rhs.fBounds.fBottom - lhs.fBounds.fTop) >> 1);
+        }
+    };
 
     SkRTree(int minChildren, int maxChildren, SkScalar aspectRatio);