layout/generic/AspectRatio.cpp

   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 #include "AspectRatio.h"
   8
   9 #include "mozilla/WritingModes.h"
  10
  11 namespace mozilla {
  12
  13 nscoord AspectRatio::ComputeRatioDependentSize(
  14     LogicalAxis aRatioDependentAxis, const WritingMode& aWM,
  15     nscoord aRatioDeterminingSize,
  16     const LogicalSize& aContentBoxSizeToBoxSizingAdjust) const {
  17   MOZ_ASSERT(*this,
  18              "Infinite or zero ratio may have undefined behavior when "
  19              "computing the size");
  20   const LogicalSize& boxSizingAdjust = mUseBoxSizing == UseBoxSizing::No
  21                                            ? LogicalSize(aWM)
  22                                            : aContentBoxSizeToBoxSizingAdjust;
  23   return aRatioDependentAxis == LogicalAxis::eLogicalAxisInline
  24              ? ConvertToWritingMode(aWM).ApplyTo(aRatioDeterminingSize +
  25                                                  boxSizingAdjust.BSize(aWM)) -
  26                    boxSizingAdjust.ISize(aWM)
  27              : ConvertToWritingMode(aWM).Inverted().ApplyTo(
  28                    aRatioDeterminingSize + boxSizingAdjust.ISize(aWM)) -
  29                    boxSizingAdjust.BSize(aWM);
  30 }
  31
  32 }  // namespace mozilla