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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef WebFont_h
#define WebFont_h
#include "WebCanvas.h"
#include "WebColor.h"
#include "WebCommon.h"
namespace WebKit {
struct WebFontDescription;
struct WebFloatPoint;
struct WebFloatRect;
struct WebPoint;
struct WebRect;
struct WebTextRun;
class WebFont {
public:
virtual ~WebFont() { }
WEBKIT_API static WebFont* create(const WebFontDescription&);
virtual WebFontDescription fontDescription() const = 0;
virtual int ascent() const = 0;
virtual int descent() const = 0;
virtual int height() const = 0;
virtual int lineSpacing() const = 0;
virtual float xHeight() const = 0;
// Draws the text run to the given canvas. The text is positioned at the
// given left-hand point at the baseline.
//
// The text will be clipped to the given clip rect. |canvasIsOpaque| is
// used to control whether subpixel antialiasing is possible. If there is a
// possibility the area drawn could be semi-transparent, subpixel
// antialiasing will be disabled.
//
// |from| and |to| allow the caller to specify a subrange of the given text
// run to draw. If |to| is -1, the entire run will be drawn.
virtual void drawText(WebCanvas*, const WebTextRun&, const WebFloatPoint& leftBaseline, WebColor,
const WebRect& clip, bool canvasIsOpaque,
int from = 0, int to = -1) const = 0;
// Measures the width in pixels of the given text run.
virtual int calculateWidth(const WebTextRun&) const = 0;
// Returns the character offset corresponding to the given horizontal pixel
// position as measured from from the left of the run.
virtual int offsetForPosition(const WebTextRun&, float position) const = 0;
// Returns the rectangle representing the selection rect for the subrange
// |from| -> |to| of the given text run. You can use -1 for |to| to specify
// the entire run (this will do something similar to calling width()).
//
// The rect will be positioned as if the text was drawn at the given
// |leftBaseline| position. |height| indicates the height of the selection
// rect you want, typically this will just be the height() of this font.
//
// To get the pixel offset of some character (the opposite of
// offsetForPosition()), pass in a |leftBaseline| = (0, 0), |from| = 0, and
// |to| = the character you want. The right edge of the resulting selection
// rect will tell you the right side of the character.
virtual WebFloatRect selectionRectForText(const WebTextRun&, const WebFloatPoint& leftBaseline,
int height, int from = 0, int to = -1) const = 0;
};
} // namespace WebKit
#endif
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