Source/WebKit/chromium/src/WebFontImpl.cpp

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

#include "Font.h"
#include "FontDescription.h"
#include "GraphicsContext.h"
#include "painting/GraphicsContextBuilder.h"
#include "TextRun.h"
#include "WebFloatPoint.h"
#include "WebFloatRect.h"
#include "WebFontDescription.h"
#include "WebRect.h"
#include "WebTextRun.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, short letterSpacing, short 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
{
    // FIXME hook canvasIsOpaque up to the platform-specific indicators for
    // whether subpixel AA can be used for this draw. On Windows, this is
    // PlatformContextSkia::setDrawingToImageBuffer.

    GraphicsContextBuilder builder(canvas);
    GraphicsContext& gc = builder.context();

    gc.save();
    gc.setFillColor(color, ColorSpaceDeviceRGB);
    gc.clip(WebCore::FloatRect(clip));
    m_font.drawText(&gc, run, leftBaseline, from, to);
    gc.restore();
}

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

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

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

} // namespace WebKit