Source/web/WebFontImpl.cpp

/*
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#include "config.h"
#include "WebFontImpl.h"

#include <skia/ext/platform_canvas.h>
#include "WebFontDescription.h"
#include "WebTextRun.h"
#include "core/platform/graphics/Font.h"
#include "core/platform/graphics/FontCache.h"
#include "core/platform/graphics/FontDescription.h"
#include "core/platform/graphics/GraphicsContext.h"
#include "core/platform/graphics/TextRun.h"
#include "public/platform/WebFloatPoint.h"
#include "public/platform/WebFloatRect.h"
#include "public/platform/WebRect.h"

using namespace WebCore;

namespace WebKit {

WebFont* WebFont::create(const WebFontDescription& desc)
{
    return new WebFontImpl(desc, desc.letterSpacing, desc.wordSpacing);
}

WebFontImpl::WebFontImpl(const FontDescription& desc, float letterSpacing, float wordSpacing)
    : m_font(desc, letterSpacing, wordSpacing)
{
    m_font.update(0);
}

WebFontDescription WebFontImpl::fontDescription() const
{
    return WebFontDescription(m_font.fontDescription(), m_font.letterSpacing(), m_font.wordSpacing());
}

int WebFontImpl::ascent() const
{
    return m_font.fontMetrics().ascent();
}

int WebFontImpl::descent() const
{
    return m_font.fontMetrics().descent();
}

int WebFontImpl::height() const
{
    return m_font.fontMetrics().height();
}

int WebFontImpl::lineSpacing() const
{
    return m_font.fontMetrics().lineSpacing();
}

float WebFontImpl::xHeight() const
{
    return m_font.fontMetrics().xHeight();
}

void WebFontImpl::drawText(WebCanvas* canvas, const WebTextRun& run, const WebFloatPoint& leftBaseline,
                           WebColor color, const WebRect& clip, bool canvasIsOpaque,
                           int from, int to) const
{
    FontCachePurgePreventer fontCachePurgePreventer;
    WebCore::FloatRect textClipRect(clip);
    TextRun textRun(run);
    TextRunPaintInfo runInfo(textRun);
    runInfo.from = from;
    runInfo.to = to == -1 ? textRun.length() : to;
    runInfo.bounds = textClipRect;
    GraphicsContext gc(canvas);

    gc.save();
    gc.setCertainlyOpaque(canvasIsOpaque);
    gc.setFillColor(color);
    gc.clip(textClipRect);
    m_font.drawText(&gc, runInfo, leftBaseline);
    gc.restore();
}

int WebFontImpl::calculateWidth(const WebTextRun& run) const
{
    FontCachePurgePreventer fontCachePurgePreventer;
    return m_font.width(run, 0);
}

int WebFontImpl::offsetForPosition(const WebTextRun& run, float position) const
{
    FontCachePurgePreventer fontCachePurgePreventer;
    return m_font.offsetForPosition(run, position, true);
}

WebFloatRect WebFontImpl::selectionRectForText(const WebTextRun& run, const WebFloatPoint& leftBaseline, int height, int from, int to) const
{
    FontCachePurgePreventer fontCachePurgePreventer;
    return m_font.selectionRectForText(run, leftBaseline, height, from, to);
}

} // namespace WebKit