1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4  * License, v. 2.0. If a copy of the MPL was not distributed with this
5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 
7 /* represent a color combines a numeric color and currentcolor */
8 
9 #ifndef mozilla_StyleComplexColor_h_
10 #define mozilla_StyleComplexColor_h_
11 
12 #include "nsColor.h"
13 
14 namespace mozilla {
15 
16 /**
17  * This struct represents a combined color from a numeric color and
18  * the current foreground color (currentcolor keyword).
19  * Conceptually, the formula is "color * (1 - p) + currentcolor * p"
20  * where p is mForegroundRatio. See mozilla::LinearBlendColors for
21  * the actual algorithm.
22  */
23 struct StyleComplexColor
24 {
25   nscolor mColor;
26   uint8_t mForegroundRatio;
27 
FromColorStyleComplexColor28   static StyleComplexColor FromColor(nscolor aColor) { return {aColor, 0}; }
CurrentColorStyleComplexColor29   static StyleComplexColor CurrentColor() { return {NS_RGBA(0, 0, 0, 0), 255}; }
30 
IsNumericColorStyleComplexColor31   bool IsNumericColor() const { return mForegroundRatio == 0; }
IsCurrentColorStyleComplexColor32   bool IsCurrentColor() const { return mForegroundRatio == 255; }
33 
34   bool operator==(const StyleComplexColor& aOther) const {
35     return mForegroundRatio == aOther.mForegroundRatio &&
36            (IsCurrentColor() || mColor == aOther.mColor);
37   }
38   bool operator!=(const StyleComplexColor& aOther) const {
39     return !(*this == aOther);
40   }
41 };
42 
43 }
44 
45 #endif // mozilla_StyleComplexColor_h_
46