[R] rgl lighting question

[Rajarshi Guha]

Thanks a lot for the pointer to rgl.pop() - that works (as does  
looking at the examples!)

On Nov 22, 2008, at 10:28 AM, Duncan Murdoch wrote:

> On 21/11/2008 2:30 PM, Rajarshi Guha wrote:
>> Hi, I'm using rgl to generate a 3D surface plot and I'm struggling  
>> to  get the lighting correct. Currently the surface gets plotted,  
>> but is  very 'shiny'. On rotating the view, I get to see parts of  
>> the surface  - but overall I don't see much detail because of the  
>> spotlight like  lighting.
>> I've played around with the specular, ambient and diffuse but I  
>> can't  bring out the details of the surface. Could anybody point  
>> me to some  examples of how to make a plain matte surface, which  
>> isn't obscured  by specular reflections?
>
> This gives the regular shiny surface:
>
> library(rgl)
> example(surface3d)
>
> This gives one with no specular reflections, because the material  
> doesn't do that:
>
> open3d()
> surface3d(x, y, z, color=col, back="lines", specular="black")
>
> And here's another way to get no specular reflections.  This time  
> there's no light to reflect that way:
>
> open3d()
> rgl.pop("lights")
> light3d(specular="black")
> surface3d(x, y, z, color=col, back="lines")
>
> I suspect you missed the rgl.pop() call.  If you just call light3d  
> or rgl.light() you'll add an additional light, you don't change the  
> existing one.
>
> Duncan Murdoch

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Rajarshi Guha  <rguha at indiana.edu>
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