Someone told me I had to use the Root Manager not the Resource Manager for placing items, though for some reason I could have sworn the dev used the latter.
Also, the reason I used so many layers together was that I was staying with the 1x1 terrain suggestion as I get a sense of scale. Not going to use the entire map; however, it helps me see how it will all come together.
I stuck with the same grass (base) texture all throughout the map, and I added the sand layer on top. I'm a little confused on your instructions. Are you talking about making a giant map instead and then painting over it rather than how I made 1x1 pieces? Or are you saying that I paint it with the same texture and then paint it with the new one? The latter would be easier to work with as I can delete the layer and then color it back in.
