Method draw

src/main/java/fieldbox/boxes/FLineDrawing.java:240–341

(DrawingInterface context)

	// we need to be able to assign blame and propagate exceptions into callbacks
	@Override
	public void draw(DrawingInterface context) {

		Util.Errors error = new Util.Errors();
		Optional<TextDrawing> text = context.getTextDrawing(this);

		this.breadthFirst(this.both())
			.forEach(Util.wrap(x -> {
				float ON = x == root ? 1 : (float) Planes.on(root, x);
				if (ON <= 0) {
					return;
				}


				Log.log("drawing.trace", () -> "lines for " + x);

				if (x.properties.isTrue(Box.hidden, false)) return;

				String defaultLayer = x.properties.getOr(layer, () -> "__main__");

				Map<String, Function<Box, FLine>> drawing = x.properties.computeIfAbsent(frameDrawing, this::defaultdrawsLines);

				List<FLine> all = new ArrayList<>();
				Iterator<Function<Box, FLine>> it = drawing.values()
					.iterator();
				while (it.hasNext()) {
					Function<Box, FLine> f = it.next();
					FLine fl = f.apply(x);
					if (fl == null) it.remove();
					else if (fl.nodes.size() > 0) all.add(fl);
				}

				Log.log("drawing.trace", () -> " --> " + drawing);

				drawing.values()
					.stream()
					.map(c -> c.apply(x))
					.filter(fline -> fline != null)
					.collect(Collectors.toList())
					.forEach(fline -> {
						dispatchLine(fline, context, text, defaultLayer, ON);
					});
				Map<String, Supplier<FLine>> ll = x.properties.getOrConstruct(lines);

				all = new ArrayList<>();
				Iterator<Supplier<FLine>> it2 = ll.values()
					.iterator();
				while (it2.hasNext()) {
					Supplier<FLine> f = it2.next();
					FLine fl = f.get();
					if (fl == null) it2.remove();
					else if (fl.nodes.size() > 0) all.add(fl);
				}

				Log.log("drawing.trace", () -> " --> " + ll);

				ll.values()
					.stream()