cleanup and optimize rect intersect routines

src/core/SkRect.cpp

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkRect.h"
@@ skipping 81 matching lines @@
         if (accum) {
             l = t = r = b = 0;
             isFinite = false;
         }
         this->set(l, t, r, b);
     }
 
     return isFinite;
 }
 
-bool SkRect::intersect(SkScalar left, SkScalar top, SkScalar right,
-                       SkScalar bottom) {
-    if (left < right && top < bottom && !this->isEmpty() && // check for empties
-        fLeft < right && left < fRight && fTop < bottom && top < fBottom)
-    {
-        if (fLeft < left) fLeft = left;
-        if (fTop < top) fTop = top;
-        if (fRight > right) fRight = right;
-        if (fBottom > bottom) fBottom = bottom;
-        return true;
-    }
-    return false;
+#define CHECK_INTERSECT(al, at, ar, ab, bl, bt, br, bb) \
+    SkScalar L = SkMaxScalar(al, bl);                   \
+    SkScalar R = SkMinScalar(ar, br);                   \
+    SkScalar T = SkMaxScalar(at, bt);                   \
+    SkScalar B = SkMinScalar(ab, bb);                   \
+    do { if (L >= R || T >= B) return false; } while (0)
+
+bool SkRect::intersect(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) {
+    CHECK_INTERSECT(left, top, right, bottom, fLeft, fTop, fRight, fBottom);
+    this->setLTRB(L, T, R, B);
+    return true;
 }
 
 bool SkRect::intersect(const SkRect& r) {
     return this->intersect(r.fLeft, r.fTop, r.fRight, r.fBottom);
 }
 
-bool SkRect::intersect2(const SkRect& r) {
-    SkScalar L = SkMaxScalar(fLeft, r.fLeft);
-    SkScalar R = SkMinScalar(fRight, r.fRight);
-    if (L >= R) {
-        return false;
-    }
-    SkScalar T = SkMaxScalar(fTop, r.fTop);
-    SkScalar B = SkMinScalar(fBottom, r.fBottom);
-    if (T >= B) {
-        return false;
-    }
-    this->set(L, T, R, B);
+bool SkRect::intersect(const SkRect& a, const SkRect& b) {
+    CHECK_INTERSECT(a.fLeft, a.fTop, a.fRight, a.fBottom, b.fLeft, b.fTop, b.fRight, b.fBottom);
+    this->setLTRB(L, T, R, B);
     return true;
 }
 
-bool SkRect::intersect(const SkRect& a, const SkRect& b) {
-
-    if (!a.isEmpty() && !b.isEmpty() &&
-        a.fLeft < b.fRight && b.fLeft < a.fRight &&
-        a.fTop < b.fBottom && b.fTop < a.fBottom) {
-        fLeft   = SkMaxScalar(a.fLeft,   b.fLeft);
-        fTop    = SkMaxScalar(a.fTop,    b.fTop);
-        fRight  = SkMinScalar(a.fRight,  b.fRight);
-        fBottom = SkMinScalar(a.fBottom, b.fBottom);
-        return true;
-    }
-    return false;
-}
-
 void SkRect::join(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) {
     // do nothing if the params are empty
     if (left >= right || top >= bottom) {
         return;
     }
 
     // if we are empty, just assign
     if (fLeft >= fRight || fTop >= fBottom) {
         this->set(left, top, right, bottom);
     } else {
         fLeft   = SkMinScalar(fLeft, left);
         fTop    = SkMinScalar(fTop, top);
         fRight  = SkMaxScalar(fRight, right);
         fBottom = SkMaxScalar(fBottom, bottom);
     }
 }
+