POV-Ray : Newsgroups : povray.newusers : How can I fix surface perfections on my render? : Re: How can I fix surface perfections on my render? Server Time
18 Sep 2021 07:01:18 EDT (-0400)
  Re: How can I fix surface perfections on my render?  
From: circuit
Date: 11 May 2020 03:20:01
Message: <web.5eb8fc1849257b654eff8dd80@news.povray.org>
Wow, this community is awesome. I appreciate all the responses.

> That _looks_ to me like it could be partly the dreaded "coincident surface"
> problem.
> You need a tiny amount of space (> 0.000001 POV units) between scene elements
> otherwise how does the renderer "know" which texture to make the pixel where 2
> objects are that occupy the same pixel?  There's some digital/coding/floating
> point error that plays into that that needs to be accounted for, thus the 1e-6
> value as insurance against it.

100% sure it's a coincident surface issue. In fact, similar artifacting also
exists in FreeCAD's rendered output. Here's an animation using FreeCAD
"activeView":

https://i.imgur.com/zljJarj.gifv

This is actually not my model... it's just the first demo file I found online
that had assembly constraints, so I ran with it. I have no idea if it was
designed properly. I plan on testing this out more thoroughly with a model I
build myself.

> Also, for preliminary developmental purposes, you may want to decrease the size
> of your renders, say to 640x480 or even 320x240, and then crank up the number of
> frames you render to give a much smoother animation.   I'd shoot for at least 15
> FPS or above for the final render.

For sure. Here's a smoother animation! This time at 20 fps:

https://i.imgur.com/6c3mLUn.gifv

It's definitely a lot quicker to render this way. I took me around 2 minutes for
the 50 frames on my i5 laptop.

> It's looking good so far  :)
> Are you running windows?
> I know that some folks on here are looking for a functioning modeler, as well as
> a way to export to .stl for 3D printing, and they may be interested in how to
> set up FreeCAD and what its capabilities are.

I am on Windows, yup, although I've played around with a few Linux distros in
the past :) I'm by no means a modeller though. I come from an electrical
background, but I have a strong interest in robotics. My plan is to use FreeCAD
to design and simulate (animate) robotic gait. Then of course, once I'm happy,
I'll 3D print the end result. POV-Ray just makes the animation quite a bit
nicer.

From my limited exposure, I'm really liking FreeCAD. I've used Fusion 3D and
Solidworks in the past, and sure, FreeCAD is not quite as polished, but it one
really great thing going for it: Python scripting. The possibilities are
limitless. Other than that, FreeCAD seems to be just as capable as the others
(but once again, I'm not a power user).

I'm happy to help provide guidance if other wants to delve into the tool.

> Yes, should use adaptive 0

I like output a lot better with this change. Edges are better defined.

Cheers everyone.


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