gecko-dev/layout/generic/CSSAlignUtils.h

65 строки
2.6 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/. */
/* Utility code for performing CSS Box Alignment */
#ifndef mozilla_CSSAlignUtils_h
#define mozilla_CSSAlignUtils_h
#include "mozilla/WritingModes.h"
namespace mozilla {
struct ReflowInput;
class CSSAlignUtils {
public:
/**
* Flags to customize the behavior of AlignJustifySelf:
*/
enum class AlignJustifyFlags {
eNoFlags = 0,
// Indicates that we have <overflow-position> = safe.
eOverflowSafe = 1 << 0,
// Indicates that the container's start side in aAxis is the same
// as the child's start side in the child's parallel axis.
eSameSide = 1 << 1,
// Indicates that AlignJustifySelf() shouldn't expand "auto" margins.
// (By default, AlignJustifySelf() *will* expand such margins, to fill the
// available space before any alignment is done.)
eIgnoreAutoMargins = 1 << 2,
};
/**
* This computes the aligned offset of a CSS-aligned child within its
* alignment container. The returned offset is distance between the
* logical "start" edge of the alignment container & the logical "start" edge
* of the aligned child (in terms of the alignment container's writing mode).
*
* @param aAlignment An enumerated value representing a keyword for
* "align-self" or "justify-self". The values
* NS_STYLE_ALIGN_{AUTO,LEFT,RIGHT} must *not* be
* passed here; this method expects the caller to have
* already resolved those to 'start', 'end', or 'stretch'.
* @param aAxis The container's axis in which we're doing alignment.
* @param aBaselineAdjust The amount to offset baseline-aligned children.
* @param aCBSize The size of the alignment container, in its aAxis.
* @param aRI A ReflowInput for the child.
* @param aChildSize The child's LogicalSize (in its own writing mode).
*/
static nscoord AlignJustifySelf(uint8_t aAlignment, LogicalAxis aAxis,
AlignJustifyFlags aFlags,
nscoord aBaselineAdjust, nscoord aCBSize,
const ReflowInput& aRI,
const LogicalSize& aChildSize);
};
MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(CSSAlignUtils::AlignJustifyFlags)
} // namespace mozilla
#endif // mozilla_CSSAlignUtils_h