While troubleshooting some problems with my LED Mapper web tool, I've added what I feel are some pretty useful new features.
Common problems with layout inputs are now reported, like non-zero start index, non-continuous sequences & duplicate indices.
You can now view numbers and/or dots in the preview & you can choose between index, X, Y, angle or radius, which can help visualize the map.
Try it here & let me know if you have any suggestions: https://jasoncoon.github.io/led-mapper