LDplot using a matrix in R

Question

[merodev]

I have a matrix of LD values for different sites. https://ibb.co/eaURxQ I would like to get a LD plot like these: https://ibb.co/cqAzHQ or https://ibb.co/mqqYcQ I want the color shades to depict the numbers but the numbers do not need to be present. Is there a way to do this in R. I looked up the LDheatmap package but it looks like it does its own calculation and I cannot figure out a way to just use matrix as an input. Thanks for any help.