mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-30 08:12:05 +00:00
c1b5d62ff4
I wrote this because I thought I was going to need the padding-box stuff for bug 221154, but I ended up not needing it. However I think it's a bit nicer, wdyt? Differential Revision: https://phabricator.services.mozilla.com/D198306
79 lines
2.8 KiB
C++
79 lines
2.8 KiB
C++
/* 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/. */
|
|
|
|
#ifndef LAYOUT_BASE_BASELINE_H_
|
|
#define LAYOUT_BASE_BASELINE_H_
|
|
|
|
#include "nsCoord.h"
|
|
#include "mozilla/WritingModes.h"
|
|
|
|
class nsIFrame;
|
|
|
|
namespace mozilla {
|
|
|
|
// https://drafts.csswg.org/css-align-3/#baseline-sharing-group
|
|
enum class BaselineSharingGroup : uint8_t {
|
|
// NOTE Used as an array index so must be 0 and 1.
|
|
First = 0,
|
|
Last = 1,
|
|
};
|
|
|
|
// Layout context under which the baseline is being exported to.
|
|
enum class BaselineExportContext : uint8_t {
|
|
LineLayout = 0,
|
|
Other = 1,
|
|
};
|
|
|
|
class Baseline {
|
|
public:
|
|
/**
|
|
* Synthesize a first(last) inline-axis baseline in aWM based on aFrame's
|
|
* margin-box.
|
|
*
|
|
* An alphabetical baseline is at the end edge of aFrame's margin-box with
|
|
* respect to aWM's block-axis, and a central baseline is halfway between the
|
|
* start and end edges. (aWM tells which baseline to use.)
|
|
* https://drafts.csswg.org/css-align-3/#synthesize-baseline
|
|
*
|
|
* @note This works only when aFrame's writing-mode is parallel to aWM.
|
|
* @param aWM the writing-mode of the alignment context.
|
|
* @return an offset from aFrame's border-box start(end) edge in aWM's
|
|
* block-axis for a first(last) baseline, respectively.
|
|
*/
|
|
static nscoord SynthesizeBOffsetFromMarginBox(const nsIFrame* aFrame,
|
|
WritingMode aWM,
|
|
BaselineSharingGroup);
|
|
|
|
/**
|
|
* Synthesize a first(last) inline-axis baseline in aWM based on aFrame's
|
|
* border-box.
|
|
*
|
|
* An alphabetical baseline is at the end edge of aFrame's border-box with
|
|
* respect to aWM's block-axis, and a central baseline is halfway between the
|
|
* start and end edges. (aWM tells which baseline to use.)
|
|
* https://drafts.csswg.org/css-align-3/#synthesize-baseline
|
|
*
|
|
* @param aWM the writing-mode of the alignment context.
|
|
* @return an offset from aFrame's border-box start(end) edge in aWM's
|
|
* block-axis for a first(last) baseline, respectively.
|
|
*/
|
|
static nscoord SynthesizeBOffsetFromBorderBox(const nsIFrame* aFrame,
|
|
WritingMode aWM,
|
|
BaselineSharingGroup);
|
|
/**
|
|
* As above, but using the content box.
|
|
*/
|
|
static nscoord SynthesizeBOffsetFromContentBox(const nsIFrame*, WritingMode,
|
|
BaselineSharingGroup);
|
|
/**
|
|
* As above, but using the padding box.
|
|
*/
|
|
static nscoord SynthesizeBOffsetFromPaddingBox(const nsIFrame*, WritingMode,
|
|
BaselineSharingGroup);
|
|
};
|
|
|
|
} // namespace mozilla
|
|
|
|
#endif // LAYOUT_BASE_BASELINE_H_
|