зеркало из https://github.com/mozilla/gecko-dev.git
94 строки
2.7 KiB
C++
94 строки
2.7 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#include "mozilla/StyleColorInlines.h"
|
|
|
|
#include "mozilla/ComputedStyle.h"
|
|
#include "mozilla/ComputedStyleInlines.h"
|
|
#include "nsIFrame.h"
|
|
#include "nsStyleStruct.h"
|
|
|
|
namespace mozilla {
|
|
|
|
// Blend one RGBA color with another based on a given ratios.
|
|
// It is a linear combination of each channel with alpha premultipled.
|
|
static nscolor LinearBlendColors(const StyleRGBA& aBg, float aBgRatio,
|
|
const StyleRGBA& aFg, float aFgRatio) {
|
|
constexpr float kFactor = 1.0f / 255.0f;
|
|
|
|
float p1 = aBgRatio;
|
|
float a1 = kFactor * aBg.alpha;
|
|
float r1 = a1 * aBg.red;
|
|
float g1 = a1 * aBg.green;
|
|
float b1 = a1 * aBg.blue;
|
|
|
|
float p2 = aFgRatio;
|
|
float a2 = kFactor * aFg.alpha;
|
|
float r2 = a2 * aFg.red;
|
|
float g2 = a2 * aFg.green;
|
|
float b2 = a2 * aFg.blue;
|
|
|
|
float a = p1 * a1 + p2 * a2;
|
|
if (a <= 0.f) {
|
|
return NS_RGBA(0, 0, 0, 0);
|
|
}
|
|
|
|
if (a > 1.f) {
|
|
a = 1.f;
|
|
}
|
|
|
|
auto r = ClampColor((p1 * r1 + p2 * r2) / a);
|
|
auto g = ClampColor((p1 * g1 + p2 * g2) / a);
|
|
auto b = ClampColor((p1 * b1 + p2 * b2) / a);
|
|
return NS_RGBA(r, g, b, NSToIntRound(a * 255));
|
|
}
|
|
|
|
template <>
|
|
bool StyleColor::MaybeTransparent() const {
|
|
// We know that the color is opaque when it's a numeric color with
|
|
// alpha == 255.
|
|
// TODO(djg): Should we extend this to check Complex with bgRatio =
|
|
// 0, and fgRatio * alpha >= 255?
|
|
return !IsNumeric() || AsNumeric().alpha != 255;
|
|
}
|
|
|
|
template <>
|
|
nscolor StyleColor::CalcColor(nscolor aColor) const {
|
|
return CalcColor(StyleRGBA::FromColor(aColor));
|
|
}
|
|
|
|
template <>
|
|
nscolor StyleColor::CalcColor(const StyleRGBA& aForegroundColor) const {
|
|
if (IsNumeric()) {
|
|
return AsNumeric().ToColor();
|
|
}
|
|
if (IsCurrentColor()) {
|
|
return aForegroundColor.ToColor();
|
|
}
|
|
MOZ_ASSERT(IsComplex());
|
|
const auto& complex = AsComplex();
|
|
return LinearBlendColors(complex.color, complex.ratios.bg, aForegroundColor,
|
|
complex.ratios.fg);
|
|
}
|
|
|
|
template <>
|
|
nscolor StyleColor::CalcColor(const ComputedStyle& aStyle) const {
|
|
// Common case that is numeric color, which is pure background, we
|
|
// can skip resolving StyleColor().
|
|
// TODO(djg): Is this optimization worth it?
|
|
if (IsNumeric()) {
|
|
return AsNumeric().ToColor();
|
|
}
|
|
return CalcColor(aStyle.StyleColor()->mColor);
|
|
}
|
|
|
|
template <>
|
|
nscolor StyleColor::CalcColor(const nsIFrame* aFrame) const {
|
|
return CalcColor(*aFrame->Style());
|
|
}
|
|
|
|
} // namespace mozilla
|