[Manifold-l] Surface tool

[CDollfus]

Hello,
i have 3 differents questions about surface and terrain projetc:
1- i would like to drap and windturbin object with he's real dimension 
(80m height): sorry this question have already posted. It will be nice 
if yoy can show me the url or explain the using step by step.
2- my second question is about visibility map: i have several points 
wich represent citys. Is it possible to draw a visibility map showing 
the areas from where we can see a defined number of cities (0 to 10 
citys in black color, 10 to 20 in red color, 30 to 40 cities in yellow...)
3- my last question is about Internet Map Server ressources: is surface 
tool functions available ? is there a sample over Intenet.
Sorry for my english, please send me questions is you need accuracy 
description,
bye and thnaks for any help