gecko-dev/dom/base/nsViewportInfo.cpp
2019-07-23 18:07:26 +00:00

53 lines
1.7 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 "nsViewportInfo.h"
#include "mozilla/Assertions.h"
#include <algorithm>
using namespace mozilla;
void nsViewportInfo::ConstrainViewportValues() {
// Non-positive zoom factors can produce NaN or negative viewport sizes,
// so we better be sure our constraints will produce positive zoom factors.
MOZ_ASSERT(mMinZoom > CSSToScreenScale(0.0f), "zoom factor must be positive");
MOZ_ASSERT(mMaxZoom > CSSToScreenScale(0.0f), "zoom factor must be positive");
if (mDefaultZoom > mMaxZoom) {
mDefaultZoomValid = false;
mDefaultZoom = mMaxZoom;
}
if (mDefaultZoom < mMinZoom) {
mDefaultZoomValid = false;
mDefaultZoom = mMinZoom;
}
}
static const float& MinOrMax(const float& aA, const float& aB,
const float& (*aMinOrMax)(const float&,
const float&)) {
MOZ_ASSERT(
aA != nsViewportInfo::ExtendToZoom && aA != nsViewportInfo::DeviceSize &&
aB != nsViewportInfo::ExtendToZoom && aB != nsViewportInfo::DeviceSize);
if (aA == nsViewportInfo::Auto) {
return aB;
}
if (aB == nsViewportInfo::Auto) {
return aA;
}
return aMinOrMax(aA, aB);
}
// static
const float& nsViewportInfo::Min(const float& aA, const float& aB) {
return MinOrMax(aA, aB, std::min);
}
// static
const float& nsViewportInfo::Max(const float& aA, const float& aB) {
return MinOrMax(aA, aB, std::max);
}