Files
MapLibreParticleLab/platform/qt/src/local_glyph_rasterizer.cpp
Bruno de Oliveira Abinader 513b50eee8 [Qt] Implement LocalGlyphRasterizer
2019-01-04 17:27:41 -04:00

75 lines
2.0 KiB
C++

#include <mbgl/text/local_glyph_rasterizer.hpp>
#include <mbgl/util/i18n.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;
};
LocalGlyphRasterizer::Impl::Impl(const optional<std::string> fontFamily_)
: fontFamily(fontFamily_) {
if (isConfigured()) {
font.setFamily(QString::fromStdString(*fontFamily));
font.setPixelSize(24);
}
}
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 util::i18n::allowsFixedWidthGlyphGeneration(glyphID) && impl->isConfigured();
}
Glyph LocalGlyphRasterizer::rasterizeGlyph(const FontStack&, GlyphID glyphID) {
Glyph glyph;
glyph.id = glyphID;
QFontMetrics metrics(impl->font);
Size size(metrics.width(glyphID), metrics.height());
glyph.metrics.width = size.width;
glyph.metrics.height = size.height;
glyph.metrics.left = 3;
glyph.metrics.top = -8;
glyph.metrics.advance = metrics.width(glyphID);
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);
painter.drawText(QPointF(0, metrics.ascent()), 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