Add ability to constrain dominant color selection to a HSL range.

ui/gfx/color_utils_unittest.cc

 // Copyright (c) 2006-2008 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 <stdlib.h>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkColorPriv.h"
 #include "ui/gfx/color_utils.h"
@@ skipping 18 matching lines @@
 TEST(ColorUtils, HSLToSkColorWithAlpha) {
   SkColor red = SkColorSetARGB(128, 255, 0, 0);
   color_utils::HSL hsl = { 0, 1, 0.5 };
   SkColor result = color_utils::HSLToSkColor(hsl, 128);
   EXPECT_EQ(SkColorGetA(red), SkColorGetA(result));
   EXPECT_EQ(SkColorGetR(red), SkColorGetR(result));
   EXPECT_EQ(SkColorGetG(red), SkColorGetG(result));
   EXPECT_EQ(SkColorGetB(red), SkColorGetB(result));
 }
 
-
 TEST(ColorUtils, RGBtoHSLRoundTrip) {
   // Just spot check values near the edges.
   for (int r = 0; r < 10; ++r) {
     for (int g = 0; g < 10; ++g) {
       for (int b = 0; b < 10; ++b) {
         SkColor rgb = SkColorSetARGB(255, r, g, b);
         color_utils::HSL hsl = { 0, 0, 0 };
         color_utils::SkColorToHSL(rgb, &hsl);
         SkColor out = color_utils::HSLToSkColor(hsl, 255);
         EXPECT_EQ(SkColorGetR(out), SkColorGetR(rgb));
@@ skipping 10 matching lines @@
         color_utils::SkColorToHSL(rgb, &hsl);
         SkColor out = color_utils::HSLToSkColor(hsl, 255);
         EXPECT_EQ(SkColorGetR(out), SkColorGetR(rgb));
         EXPECT_EQ(SkColorGetG(out), SkColorGetG(rgb));
         EXPECT_EQ(SkColorGetB(out), SkColorGetB(rgb));
       }
     }
   }
 }
 
+TEST(ColorUtils, IsWithinHSLRange) {
+  color_utils::HSL hsl = {0.3, 0.4, 0.5};
+  {
+    color_utils::HSL lower = {0.2, 0.3, 0.4};
+    color_utils::HSL upper = {0.4, 0.5, 0.6};
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    // Bounds are inclusive.
+    hsl.h = 0.2;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.h = 0.4;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.s = 0.3;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.s = 0.5;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.l = 0.4;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.l = 0.6;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+  }
+  {
+    // Check hue wrap-around.
+    color_utils::HSL lower = {0.8, -1, -1};
+    color_utils::HSL upper = {1.2, -1, -1};
+    hsl.h = 0.1;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.h = 0.9;
+    EXPECT_TRUE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+    hsl.h = 0.3;
+    EXPECT_FALSE(color_utils::IsWithinHSLRange(hsl, lower, upper));
+  }
+}
 TEST(ColorUtils, ColorToHSLRegisterSpill) {
   // In a opt build on Linux, this was causing a register spill on my laptop
   // (Pentium M) when converting from SkColor to HSL.
   SkColor input = SkColorSetARGB(255, 206, 154, 89);
   color_utils::HSL hsl = { -1, -1, -1 };
   SkColor result = color_utils::HSLShift(input, hsl);
   // |result| should be the same as |input| since we passed in a value meaning
   // no color shift.
   EXPECT_EQ(SkColorGetA(input), SkColorGetA(result));
   EXPECT_EQ(SkColorGetR(input), SkColorGetR(result));
@@ skipping 11 matching lines @@
               back);
 
   // One is fully transparent, result is partially transparent.
   back = SkColorSetA(back, 0);
   EXPECT_EQ(136U, SkColorGetA(color_utils::AlphaBlend(fore, back, 136)));
 
   // Both are fully transparent, result is fully transparent.
   fore = SkColorSetA(fore, 0);
   EXPECT_EQ(0U, SkColorGetA(color_utils::AlphaBlend(fore, back, 255)));
 }