Problems updating Graphics3D Polygons

*To*: mathgroup at smc.vnet.net*Subject*: [mg77570] Problems updating Graphics3D Polygons*From*: chuck009 <dmilioto at comcast.com>*Date*: Wed, 13 Jun 2007 07:28:25 -0400 (EDT)

Hello guys. Can you help me write a function which takes a Graphics3D object and multiplies the z-coordinate of each point of all the polygons by a ratio. This is what I have so far but it's not working: In[473]:= ExpandZ[g_,ratio_]:= g/.Polygon[pts_]:>Polygon[{#[[1]],#[[2]],#[[3]]*ratio}& /@pts]; When I test it with this simple Graphics3D object: gobject=Graphics3D[{Polygon[{{0.,0.5,1.28},{0.,0.,1.},{0.5,0.,1.28},{0.5, 0.5,1.64}}],Polygon[{{ 0.5,0.5,1.64},{0.5,0.,1.28},{1.,0.,2.71},{1.,0.5,3.49}}]}]; It doesn't do anything: g2=Expand[gobject,2] InputForm[g2] Out[475]= â??Graphics3Dâ?? Out[476]//InputForm= Graphics3D[{Polygon[{{0., 0.5, 1.28}, {0., 0., 1.}, {0.5, 0., 1.28}, {0.5, 0.5, 1.64}}], Polygon[{{0.5, 0.5, 1.64}, {0.5, 0., 1.28}, {1., 0., 2.71}, {1., 0.5, 3.49}}]}] I'll keep working on it. Thanks!