Jeremy M. Praay wrote:
> "Jim Charter" <jrc### [at] msncom> wrote in message 
> news:4210db55@news.povray.org...
> 
> 
>>Beautiful.  Some really nice subtlties like the way the tacks sink into 
>>the wood grain and the vertical drizzle of yellow.
> 
> 
> :-)
> 
> 
>>So I take it you are combining UV mapping with procedural texture or did 
>>you lay the texture down on the imagemap along with the strip shapes?
> 
> 
> UV-mapping?  Blasphemy!  ;-)
> 
> It's all procedural.  

Okay ;) I would have thought it odd if it wasn't but I just wanted to be 
sure.  I think to be fair, if you use the hf_cylinder macro you are 
using a type of uv mapping implicitly, in the sense that a uv space is 
being projected, which is what I meant.

I think I used about 5-6 layers of texture to create
> the wood.  Actually, I have nothing against uv-mapping, but I generally find 
> it easier (and more fulfilling) to use procedural unless I'm dealing with 
> something where pictures/drawings are involved. 

Well the fine grain of the wood is *extremely* convincing whatever the 
case. So you are using a texture like granite or crackle which works the 
same in all dimensions and so appears to wrap very well, especially on 
regular shapes.  This is also my preferred solution.  Are you applying a 
normal too it looks like?

But you are dealing with drawing aren't you?


  But I don't want to paint
> myself into a corner, either.  Playing around with Gilles' Mini Cooper demo 
> taught me a lot about how to use heightfields in conjunction with 
> photographic textures, and some day I may make use of that.  For example, 
> it's difficult (though not impossible) to produce "wear" in the proper 
> places by using procedural textures.  But I digress...

Yeah I was just playing with putting functions into hf's myself in the 
hope of speeding up the isowood.inc for limited applications or for 
testing, but the way the pattern gets transformed when applied to the hf 
object is fairly mind-bending. ie it seems to automatically rotate the 
wood pattern to align it with the vertical. Incidently I don't know if I 
am experiencing a "senior moment" but I could not find where it is 
covered in the official docs, how to apply functions to hf's.  I had to 
go rummaging through old files to remember.

> 
> To make the fingers have a different texture than the wood that they are 
> tacked onto, I simply made a cylinder slightly larger than most of the 
> heightfield cylinder (technically an isosurface) and said "translate x*20" 
> for the texture.  I experimented with more complex solutions ("cylindrical" 
> pigments), but that was the simplest solution.
> 
> I had a difficult time forcing myself to use a heightfield, and I actually 
> produced a version that was pure CSG. 

How?  You are still dependent on the image_map to displace the "fingers" 
are you not?  I can picture uv mapping the image to a cylinder, and I 
can picture making the image a function and displacing an iso's surface 
with it, but I can't picture doing both.

  But with the heightfield, I was able
> to make the tack holes, and then place the tacks in them one at a time, as 
> well as to make the "fingers" a little bit round.  Basically, it was about 
> the same process that I used for my old radios (the "face-plates" were all 
> heightfields), except wrapped around a cylinder.  Anyway, I think it makes 
> for a more realistic object, while keeping all of the benefits of using CSG.
> 

Well it is a very cool result and it stands up to magnification very well

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