Method fill

src/main/java/field/graphics/FLine.java:1293–1309

(int slot, int start, int end, List<Node> target)

		int dim;
		if (a == null) dim = b.length;
		else if (b == null) dim = a.length;
		else dim = Math.min(b.length, a.length);

		for (int i = start; i < end + 1; i++) {
			float alpha = (i - start) / ((float) end - start);
			if (Float.isNaN(alpha)) alpha = 0;
			float[] val = interpolate(alpha, a, b, dim);
			target.get(i).flatAuxData[slot] = val;
		}
	}

	private float[] interpolate(float alpha, float[] a, float[] b, int dim) {
		if (a == null) return b;
		if (b == null) return a;
		float[] r = new float[dim];
		for (int i = 0; i < r.length; i++)
			r[i] = a[i] * (1 - alpha) + b[i] * alpha;
		return r;
	}