Hi all, I'm finally back on the newsgroups, after a *long* break due to a
difficult move.  Had no reliable 'net connection until now, except at the local
library (limited to 1/2 hour per session!) I *do* need a laptop...

I'm still catching up with POV-Ray's interesting new developments and associated
newsgroup posts--Halton randomness, 'emission' in place of ambient, the new mesh
camera, SSLT etc. Very cool stuff...still trying to understand it all. Kudos to
all the developers!

Meanwhile, I haven't been idle...

The movie AVATAR inspired me to try and make some animated wind-blown grass. It
turned out to be relatively easy, and worked first-time! (Well, in the
*simplistic* way that I went about it.) The mesh grass blades don't actually
bend *along* their lengths, they just rotate at their bases--mostly around z,
but a bit around y as well. Yet the result still looks rather cool.

This is a representative static image; I'll be posting the animation over at
p.b.a.

The idea is like a 'noise cloud' moving through the grass, causing each blade to
rotate *more* or *less*. I used eval_pigment (operating on several
averaged-together, moving bumps patterns) to produce the individual rotation
amounts at any particular spot--the 'wind.' The evaluation points for the
pattern(s) are the same as the random traced positions that place the grass
blades onto the main height_field. That simplified things: no need to do
multiple traces for grass AND eval_pigment; and it 'locked' the moving wind
patterns to the individual grass blades.

The anchor, seashells and etc. are mainly just 'filler'--to give the scene some
interest and scale. (Although they were fun to make.) The anchor is an sPatch
mesh model, with lots of POV spheres added/subtracted. The shells are simply
image_mapped spheres, to get a curved shape (the shell artwork was done in
Photoshop.) The back half of each sphere is then clipped off, to eliminate the
'other visible side.'

A last-minute addition was some 'sand' blowing across the dunes. For that, I
duplicated the dune HF, elevated it a bit in y, and added a mostly-transparent
moving texture--so the wispy sand 'hugs' the sand dunes.

Comments and questions welcome as always.

Ken W.

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