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#include <mbgl/text/local_glyph_rasterizer.hpp>
#include <mbgl/util/i18n.hpp>
#include <mbgl/util/constants.hpp>
#include <QtCore/QFile>
#include <QtGui/QFont>
#include <QtGui/QImage>
#include <QtGui/QPainter>
#include <qglobal.h>
namespace mbgl {
class LocalGlyphRasterizer::Impl {
public:
Impl(const optional<std::string> fontFamily_);
bool isConfigured() const;
optional<std::string> fontFamily;
QFont font;
optional<QFontMetrics> metrics;
};
LocalGlyphRasterizer::Impl::Impl(const optional<std::string> fontFamily_)
: fontFamily(fontFamily_) {
if (isConfigured()) {
font.setFamily(QString::fromStdString(*fontFamily));
font.setPixelSize(util::ONE_EM);
metrics = QFontMetrics(font);
}
}
bool LocalGlyphRasterizer::Impl::isConfigured() const {
return fontFamily.operator bool();
}
LocalGlyphRasterizer::LocalGlyphRasterizer(const optional<std::string> fontFamily)
: impl(std::make_unique<Impl>(fontFamily)) {
}
LocalGlyphRasterizer::~LocalGlyphRasterizer() {
}
bool LocalGlyphRasterizer::canRasterizeGlyph(const FontStack&, GlyphID glyphID) {
return impl->isConfigured() && impl->metrics->inFont(glyphID) && util::i18n::allowsFixedWidthGlyphGeneration(glyphID);
}
Glyph LocalGlyphRasterizer::rasterizeGlyph(const FontStack&, GlyphID glyphID) {
Glyph glyph;
glyph.id = glyphID;
if (!impl->isConfigured()) {
assert(false);
return glyph;
}
glyph.metrics.width = impl->metrics->width(glyphID);
glyph.metrics.height = impl->metrics->height();
glyph.metrics.left = 3;
glyph.metrics.top = -8;
glyph.metrics.advance = glyph.metrics.width;
// Set width of a glyph's backing image to be util::ONE_EM.
Size size(util::ONE_EM, glyph.metrics.height);
QImage image(QSize(size.width, size.height), QImage::Format_Alpha8);
image.fill(qRgba(0, 0, 0, 0));
QPainter painter(&image);
painter.setFont(impl->font);
painter.setRenderHints(QPainter::TextAntialiasing);
// Render at constant baseline, to align with glyphs that are rendered by node-fontnik.
painter.drawText(QPointF(0, 20), QString(QChar(glyphID)));
auto img = std::make_unique<uint8_t[]>(image.byteCount());
memcpy(img.get(), image.constBits(), image.byteCount());
glyph.bitmap = AlphaImage { size, std::move(img) };
return glyph;
}
} // namespace mbgl
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