rem                            PT_GRV3.CDL


rem        Copy Right by International Technology Transfer Corp.
rem        revision 1.0 7/30/99   


rem        Calculate the center of gravity



clear
defopt = 2
acc = 0.00001

:start
getpos "Indicate First Point",defopt

on (@key + 3) goto exit, start, start,
defopt=@key
wx1 = @xworld
wy1 = @yworld
wz1 = @zworld

:second
getpos "Indicate Second Point",defopt

on (@key + 3) goto exit, start, second, 
defopt=@key
wx2 = @xworld
wy2 = @yworld
wz2 = @zworld

:third
getpos "Indicate Third Point",defopt

on (@key + 3) goto exit, second, third, 
defopt=@key
wx3 = @xworld
wy3 = @yworld
wz3 = @zworld

x = (wx1 + wx2 + wx3) / 3
y = (wy1 + wy2 + wy3) / 3
z = (wz1 + wz2 + wz3) / 3

point x, y, z
redraw
goto start
:exit