Method rasterizeMap

src/tools/fill_tool.cpp:250–317

}

QImage FillTool::rasterizeMap(const QRectF& extent, QTransform& out_transform)
{
	// Draw map into a QImage with the following settings:
	// - specific zoom factor (resolution)
	// - no antialiasing
	// - encode object ids in object colors
	// - draw baselines in advance to normal rendering
	//   This makes it possible to fill areas bounded by e.g. dashed paths.
	
	constexpr auto zoom_level = qreal(4);
	
	// Create map view centered on the extent
	MapView view{ map() };
	view.setCenter(MapCoord{ extent.center() });
	view.setZoom(zoom_level);
	
	// Allocate the image
	auto image_size = view.calculateViewBoundingBox(extent).toAlignedRect().size();
	QImage image = QImage(image_size, QImage::Format_RGB32);
	image.fill(background);
	
	// Draw map
	RenderConfig::Options options = RenderConfig::DisableAntialiasing | RenderConfig::ForceMinSize;
	RenderConfig config = { *map(), extent, view.calculateFinalZoomFactor(), options, 1.0 };
	
	QPainter painter;
	painter.begin(&image);
	painter.translate(image_size.width() / 2.0, image_size.height() / 2.0);
	painter.setWorldTransform(view.worldTransform(), true);
	
	auto original_area_hatching = map()->isAreaHatchingEnabled();
	if (original_area_hatching)
	{
		map()->setAreaHatchingEnabled(false);
	}
	
	if (!map()->isBaselineViewEnabled())
	{
		// Temporarily enable baseline view and draw map once.
		map()->setBaselineViewEnabled(true);
		map()->getCurrentPart()->applyOnAllObjects(&Object::forceUpdate);
		drawObjectIDs(map(), &painter, config);
		map()->setBaselineViewEnabled(false);
		map()->getCurrentPart()->applyOnAllObjects(&Object::forceUpdate);
	}
	else if (original_area_hatching)
	{
		map()->getCurrentPart()->applyOnAllObjects(&Object::forceUpdate);
	}
	
	// Draw the map in original mode (but without area hatching)
	drawObjectIDs(map(), &painter, config);
	
	if (original_area_hatching)
	{
		map()->setAreaHatchingEnabled(original_area_hatching);
		map()->getCurrentPart()->applyOnAllObjects(&Object::forceUpdate);
	}