POV-Ray : Newsgroups : povray.general : Conic_sweep + orthographic: gotcha or bug? Server Time
1 Aug 2024 06:19:44 EDT (-0400)
  Conic_sweep + orthographic: gotcha or bug? (Message 1 to 1 of 1)  
From: Antti Arola
Subject: Conic_sweep + orthographic: gotcha or bug?
Date: 16 Apr 2006 12:18:35
Message: <slrne44rir.chk.aea@basal.localdomain>
In an attempt to teach myself some basic aspects of SDL I've
dutifully avoided for the last umpteen years, I came across
an annoying peculiarity in a prism with conic_sweep: when viewed 
head-on from the top, using an orthographic camera, the sloped
sides show only as blackness. As far as I can tell, any other
angle, or perspective camera at any angle, works fine.
Is this just another gotcha easily fixed once you know how to
spot, fix, and avoid it, like coincident surfaces, or a real bug?

Version of POV-Ray: 3.61, official Linux binary, running on
Debian Sarge.

Near-minimal scene, with the prism taken straight from the scene
file I was working on:
---<snip>---
plane { -y, -4 pigment { color rgb 0.8 } } // for background

prism {
	conic_sweep
	linear_spline
	0.625, 1,
	5
	<2, 2>, <2, -2>, <-2, -2>, <-2, 2>, <2, 2>
	pigment { color rgb <1, 0.5, 0> }
}

light_source { <8, -11, 5> color rgb <1, 1, 1> }

camera {
	orthographic
	location <0, -10, 0>
	look_at <0, 0, 0>
}
---<snip>---

-- 
Antti Arola, edistyksenvastainen retropaskiainen
ant### [at] gmailcom for first contact by unknown parties, please.


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