POV-Ray : Newsgroups : povray.binaries.images : Sphere sweep woes : Re: Sphere sweep woes Server Time
9 Aug 2024 11:21:33 EDT (-0400)
  Re: Sphere sweep woes  
From: Ken
Date: 21 Feb 2005 20:05:01
Message: <web.421a8376c206a00416b983d30@news.povray.org>
"Tim McMurdo" <jod### [at] wohrrcom> wrote:
> Back to modelling on the ship. I was referencing some photos of actual ships
> rigging when I noticed that rope comes in many shades depending on the wear
> and age of the rope (I am guessing). SO I thought I would revisit the macro
> that piles loops of rope on the belaying pins and have it vary the shade of
> the rope randomly withing a given range. That seems to work out pretty
> well, however...I don't like the fact that the texture does not follow the
> sphere sweep, but is applied to the entire sphere sweep after the fact. I
> can not find a fix for this in the documents. Does anybody know if there is
> a fix?
>
> Tim

 The rigging on sailing ships comes in two types: Standing rigging and
running rigging. Standing rigging is used for shrouds, stays etc. Running
rigging is used for sheets, sail trimming etc. The standing rigging is
tared for weather protection, while the running rigging is not. As a result,
standing rigging is almist black, while running
rigging will vary in color as it ages, from light tan to grey. Also, there
are two types of rope: Rope
and cable. Rope has a clock-wise or right-hand twist, while cable has a
counterclock-wise or lefthand twist.

As a side note, your model should have some shear to it, i.e. a upward bend
to the side of the ship. The shear follows a circle of very large radius.
This radius increasted over time. During the Elisabethan era it was rather
small. By the end of the Age-of-Sail it had increased to the point that the
shear was almost gone. A good referance is Dean's Doctrine of Naval
Architecture, 1670. It is available in re-print.

Ken Matassa


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