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Revealing HiddenSurfaces
Posted:
Jul 17, 1996 1:48 AM


Could someone help on this? Thanks.
I want to plot two things in a single 3D graph. One thing is just a surface which I can do easily enough as ...
model = Plot3D[(x + y)/2, {x,0,25},{y,0,25}, PlotPoints > 2, Shading > False, HiddenSurface > False]
where I can see the hidden surface. Superimposed on this I wanted data points (where the ÃÂerrorÃÂ¹ distance between each data point and the model surface is shown by a vertical line). I did this in two steps. First make the error lines with the example set ...
data = Show[Graphics3D[{Line[{{0,1.97,0.98},{0,1.97,0.99}}], Line[{{0,8.72,4.02},{0,8.72,4.36}}], Line[{{0,22.1,8.38},{0,22.1,11.05}}]}, Axes > True]]
Finally plot everything together.
Show[data, model, Shading > False]
The problem is that IÃÂ¹m unable to make the model surface transparent so that I can see the error lines of the data points behind the surface. Unfortunately Graphics3D doesnÃÂ¹t have a HiddenSurface option (Plot3D and Show do). Is there some way of doing this (maybe converting data to some other kind of graphics object)? This has been bugging me and I would really appreciate some pointers. Thanks.
David dsmith@psy.ucsd.edu



