Add base types for path ops

src/pathops/SkPathOpsBounds.h

+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#ifndef SkPathOpBounds_DEFINED
+#define SkPathOpBounds_DEFINED
+
+#include "SkPathOpsRect.h"
+#include "SkRect.h"
+
+// SkPathOpsBounds, unlike SkRect, does not consider a line to be empty.
+struct SkPathOpsBounds : public SkRect {
+    static bool Intersects(const SkPathOpsBounds& a, const SkPathOpsBounds& b) {
+        return a.fLeft <= b.fRight && b.fLeft <= a.fRight &&
+                a.fTop <= b.fBottom && b.fTop <= a.fBottom;
+    }
+
+    // FIXME: add() is generically useful and could be added directly to SkRect
+    void add(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) {
+        if (left < fLeft) fLeft = left;
+        if (top < fTop) fTop = top;
+        if (right > fRight) fRight = right;
+        if (bottom > fBottom) fBottom = bottom;
+    }
+
+    void add(const SkPathOpsBounds& toAdd) {
+        add(toAdd.fLeft, toAdd.fTop, toAdd.fRight, toAdd.fBottom);
+    }
+
+    void add(const SkPoint& pt) {
+        if (pt.fX < fLeft) fLeft = pt.fX;
+        if (pt.fY < fTop) fTop = pt.fY;
+        if (pt.fX > fRight) fRight = pt.fX;
+        if (pt.fY > fBottom) fBottom = pt.fY;
+    }
+
+    // unlike isEmpty(), this permits lines, but not points
+    // FIXME: unused for now
+    bool isReallyEmpty() const {
+        // use !<= instead of > to detect NaN values
+        return !(fLeft <= fRight) || !(fTop <= fBottom)
+                || (fLeft == fRight && fTop == fBottom);
+    }
+
+    void setCubicBounds(const SkPoint a[4]);
+    void setLineBounds(const SkPoint a[2]);
+    void setQuadBounds(const SkPoint a[3]);
+
+    void setPointBounds(const SkPoint& pt) {
+        fLeft = fRight = pt.fX;
+        fTop = fBottom = pt.fY;
+    }
+    
+    typedef SkRect INHERITED;
+};
+
+extern void (SkPathOpsBounds::*SetCurveBounds[])(const SkPoint[]);
+
+#endif