A host of micro-optimizations and a refactor of TimeForBoundsToIntersect

cc/tile_priority_unittest.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/tile_priority.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace cc {
 namespace {
 
 TEST(TilePriorityTest, TimeForBoundsToIntersectWithScroll) {
+  const float inf = std::numeric_limits<float>::infinity();
   gfx::Rect target(0, 0, 800, 600);
   gfx::Rect current(100, 100, 100, 100);
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-200, 0, 100, 100), current, 1, target));
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-100, 0, 100, 100), current, 1, target));
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(400, 400, 100, 100), current, 1, target));
 
   current = gfx::Rect(-300, -300, 100, 100);
-  EXPECT_EQ(1000, TilePriority::TimeForBoundsToIntersect(
+  EXPECT_EQ(inf, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(0, 0, 100, 100), current, 1, target));
-  EXPECT_EQ(1000, TilePriority::TimeForBoundsToIntersect(
+  EXPECT_EQ(inf, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-200, -200, 100, 100), current, 1, target));
   EXPECT_EQ(2, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-400, -400, 100, 100), current, 1, target));
 }
 
 TEST(TilePriorityTest, TimeForBoundsToIntersectWithScale) {
+  const float inf = std::numeric_limits<float>::infinity();
   gfx::Rect target(0, 0, 800, 600);
   gfx::Rect current(100, 100, 100, 100);
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-200, 0, 200, 200), current, 1, target));
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-100, 0, 50, 50), current, 1, target));
   EXPECT_EQ(0, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(400, 400, 400, 400), current, 1, target));
 
   current = gfx::Rect(-300, -300, 100, 100);
-  EXPECT_EQ(1000, TilePriority::TimeForBoundsToIntersect(
+  EXPECT_EQ(inf, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-400, -400, 300, 300), current, 1, target));
   EXPECT_EQ(8, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-275, -275, 50, 50), current, 1, target));
   EXPECT_EQ(1, TilePriority::TimeForBoundsToIntersect(
       gfx::Rect(-450, -450, 50, 50), current, 1, target));
 }
 
 TEST(TilePriorityTest, ManhattanDistanceBetweenRects) {
   EXPECT_EQ(0, TilePriority::manhattanDistance(
       gfx::RectF(0, 0, 400, 400), gfx::RectF(0, 0, 100, 100)));
 
   EXPECT_EQ(2, TilePriority::manhattanDistance(
       gfx::Rect(0, 0, 400, 400), gfx::Rect(-100, -100, 100, 100)));
 
   EXPECT_EQ(1, TilePriority::manhattanDistance(
       gfx::Rect(0, 0, 400, 400), gfx::Rect(0, -100, 100, 100)));
 
   EXPECT_EQ(202, TilePriority::manhattanDistance(
       gfx::Rect(0, 0, 100, 100), gfx::Rect(200, 200, 100, 100)));
 }
 
 }  // namespace
 }  // namespace cc