RoC ONLY Quesion about SetTerrainType()

Lacking TFT, I'm trying to program in a SetTerrainType into my maze using a line from JASS.

I'm told it requires this:

call SetTerrainType(GetLocationX(where), GetLocationY(where), terrainType, variation, area, shape)

I put the smallest area as the integer 1, but I got a square of 3x3. How do I just change one terrain tile (the smallest) instead of 9 at once? Also, where would I find the integer values for JASS for terraintype, variation, and shape?

Thanks.

Did you try 1 as shape? 0 as shape is a circle and as 1 it is a square.
Area should be fine at 1 as long as you set the shape to a square.
A -1 variation means that a random texture variation will be chosen (for example some grass tiles' variations have small rocks or small dirt holes within their limits). You don't want to use a custom variation in most of the cases anyway.

As for location, you probably want to use a 128x128 grid's vertex, as any single terrain tile is always centered on one.