Drop this script into any prim, and touch a face. You will be informed of the face number, and the face you touched will be highlighted for 2 seconds. If the script is placed in the root prim, you will be informed of the link number, and the face, that you touched.
An invaluable tool for builders wanting to address faces and prims directly by number through a simple script of their own.
Don't bother. Script is free on wiki
default
{
touch_start(integer num_detected)
{
integer face = llDetectedTouchFace(0);
if (face == TOUCH_INVALID_FACE)
{
llSay(PUBLIC_CHANNEL, "The touched face could not be determined");
}
else
{
llSay(PUBLIC_CHANNEL, "You touched face number " + (string) face);
}
}
}