Method renderTest

test/symbol_t.cpp:248–297

	}
	
	void renderTest()
	{
		QFETCH(QString, map_filename);
		QFETCH(qreal, pixel_per_mm);
		
		Map map;
		QVERIFY(map.loadFrom(map_filename));
		
		// Don' test text symbols: text rendering requires more Qt GUI,
		// and it depends on fonts and platforms.
		for (auto i = 0; i < map.getNumSymbols(); ++i)
		{
			auto* symbol = map.getSymbol(i);
			if (symbol && symbol->getType() == Symbol::Text)
				symbol->setIsHelperSymbol(true);
		}
		
		const auto extent = map.calculateExtent().toAlignedRect().adjusted(-1, -1, +1, +1);
		
		auto image = QImage{pixel_per_mm * extent.size(), QImage::Format_ARGB32_Premultiplied};
		image.fill(QColor(Qt::white));
		
		QPainter painter{&image};
		painter.setRenderHint(QPainter::Antialiasing, false);
		painter.scale(pixel_per_mm, pixel_per_mm);
		painter.translate(-extent.topLeft());
		painter.setClipRect(extent);
		map.draw(&painter, RenderConfig{map, extent, pixel_per_mm, RenderConfig::DisableAntialiasing, 1});
		painter.end();
		
		auto image_filename = QFileInfo{map_filename}.absoluteFilePath();
		image_filename.chop(4);
		image_filename.append(QLatin1String{"png"});
		
#ifdef MAPPER_DEVELOPMENT_BUILD
		auto out_filename = image_filename;
		out_filename.insert(image_filename.length() - 4, QLatin1String(".tmp"));
		QVERIFY(image.save(out_filename, "PNG", 1));
#endif
		
		QVERIFY(QFileInfo::exists(image_filename));
		QImage expected_image;
		QVERIFY(expected_image.load(image_filename));
		image = image.convertToFormat(expected_image.format());
		QCOMPARE(fuzzyDifference(image, expected_image), QPoint(-1,-1));
		
#ifdef MAPPER_DEVELOPMENT_BUILD
		QVERIFY(QFile::remove(out_filename));
#endif
	}
	
	
	void invariantTest_data()