2D mapping LED's for animation

I'm building an LED mask for fun that I saw online. In some of the posts the designer talks about 2D mapping the LED's to create cool designs. Can anyone point me in the right direction on how I might accomplish this? I've looked for tools/software to help but haven't found anything that great. Any advice appreciated.

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All that means is that there is an array that holds the LED’s position. So a two dimensional array, at location [12][6] would contain the LED number of the strip that contains an LED in the position 12 across and 6 down.

You have to define this array depending on how you wired it up. Yes you can wire it up how you like, you just alter the array to suite. I would call this a look up table but I suppose mapping sounds more whizzing.