RmlUi/Source/Core/LayoutLineBox.h

/*
 * This source file is part of RmlUi, the HTML/CSS Interface Middleware
 *
 * For the latest information, see http://github.com/mikke89/RmlUi
 *
 * Copyright (c) 2008-2010 CodePoint Ltd, Shift Technology Ltd
 * Copyright (c) 2019 The RmlUi Team, and contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 */

#ifndef RMLUI_CORE_LAYOUTLINEBOX_H
#define RMLUI_CORE_LAYOUTLINEBOX_H

#include "LayoutInlineBox.h"

namespace Rml {

class LayoutBlockBox;

/**
	@author Peter Curry
 */

class LayoutLineBox
{
public:
	LayoutLineBox(LayoutBlockBox* parent);
	~LayoutLineBox();

	/// Closes the line box, positioning all inline elements within it.
	/// @param overflow[in] The overflow box from a split inline box that caused this line to close. Leave this as nullptr if we closed naturally.
	/// @return If there was any overflow, this will be the last element generated by the spilling content. Otherwise, this will be nullptr.
	LayoutInlineBox* Close(UniquePtr<LayoutInlineBox> overflow = nullptr);

	/// Closes one of the line box's inline boxes.
	/// @param inline_box[in] The inline box to close. This should always be the line box's open box.
	void CloseInlineBox(LayoutInlineBox* inline_box);

	/// Attempts to add a new element to this line box. If it can't fit, or needs to be split, new line boxes will
	/// be created. The inline box for the final section of the element will be returned.
	/// @param element[in] The element to fit into this line box.
	/// @param box[in] The element's extents.
	/// @return The inline box for the element.
	LayoutInlineBox* AddElement(Element* element, const Box& box);

	/// Attempts to add a new inline box to this line. If it can't fit, or needs to be split, new line boxes will
	/// be created. The inline box for the final section of the element will be returned.
	/// @param box[in] The inline box to be added to the line.
	/// @return The final inline box.
	LayoutInlineBox* AddBox(UniquePtr<LayoutInlineBox> box);
	/// Adds an inline box as a chained hierarchy overflowing to this line. The chain will be extended into
	/// this line box.
	/// @param split_box[in] The box overflowed from a previous line.
	void AddChainedBox(LayoutInlineBox* chained_box);

	/// Returns the position of the line box, relative to its parent's block box's content area.
	/// @return The position of the line box.
	Vector2f GetPosition() const;
	/// Returns the position of the line box, relative to its parent's block box's offset parent.
	/// @return The relative position of the line box.
	Vector2f GetRelativePosition() const;
	/// Returns the dimensions of the line box.
	/// @return The dimensions of the line box.
	Vector2f GetDimensions() const;

	/// Returns the line box's open inline box.
	/// @return The line's open inline box, or nullptr if it currently has none.
	LayoutInlineBox* GetOpenInlineBox();
	/// Returns the line's containing block box.
	/// @return The line's block box.
	LayoutBlockBox* GetBlockBox();

	float GetBoxCursor() const;

	bool GetBaselineOfLastLine(float& baseline) const;

	void* operator new(size_t size);
	void operator delete(void* chunk, size_t size);

private:
	/// Appends an inline box to the end of the line box's list of inline boxes. Returns a pointer to the appended box.
	LayoutInlineBox* AppendBox(UniquePtr<LayoutInlineBox> box);

	using InlineBoxList = Vector< UniquePtr<LayoutInlineBox> >;

	// The block box containing this line.
	LayoutBlockBox* parent;

	// The top-left position of the line box; this is set when the first inline box is placed.
	Vector2f position;
	bool position_set;

	// The width and height of the line box; this is set when the line box is placed.
	Vector2f dimensions;
	bool wrap_content;

	// The horizontal cursor. This is where the next inline box will be placed along the line.
	float box_cursor;

	// The list of inline boxes in this line box. These line boxes may be parented to others in this list.
	InlineBoxList inline_boxes;
	// The open inline box; this is nullptr if all inline boxes are closed.
	LayoutInlineBox* open_inline_box;
};

} // namespace Rml
#endif