POV-Ray : Newsgroups : povray.object-collection : Rope macros Server Time: 26 Jun 2019 09:47:01 GMT
  Rope macros (Message 1 to 7 of 7)  
From: gil
Subject: Rope macros
Date: 16 Aug 2009 17:45:00
Message: <web.4a8844eb891b2f264c5582dd0@news.povray.org>
Having a requirement for ropes in my project, I sprang with delight on the Rope
macros. However, whether I use the supplied rope.pov, or incorporate the
examples in my own pov file, the ropes are almost invisible. On close
inspection, they appear to be composed of coloured flecks, which may be the
fibre highlights, but the substance of the ropes appears transparent. I am
using povRay 3.6.

Any suggestions?

Gil

PS I hope this is the right topic... Apologies if not.


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From: StephenS
Subject: Re: Rope macros
Date: 16 Aug 2009 19:10:00
Message: <web.4a8859323e39793b37d670520@news.povray.org>
"gil" <nomail@nomail> wrote:
> Having a requirement for ropes in my project, I sprang with delight on the Rope
> macros. However, whether I use the supplied rope.pov, or incorporate the
> examples in my own pov file, the ropes are almost invisible. On close
> inspection, they appear to be composed of coloured flecks, which may be the
> fibre highlights, but the substance of the ropes appears transparent. I am
> using povRay 3.6.
>
> Any suggestions?
>
> Gil
>
> PS I hope this is the right topic... Apologies if not.

Can you give an example of how you're envoking the macros.
example:
#include "Rope.inc"
Rope_Undef()
#declare Rope_Catenary_a = 15; // 1 default
Rope_AddPoint (<0,0,0>)
#declare Rope_SplineIncrement = 0.01; //.001 default
#declare Rope_LengthChunks    = 100; //1000 default
Rope_Catenary(<20,0,0>)
Rope_ArrayToRope("")

and what is the scale of some of your scene elements?

Stephen S


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From: Chris B
Subject: Re: Rope macros
Date: 16 Aug 2009 21:11:16
Message: <4a8875f4@news.povray.org>
"StephenS" <nomail@nomail> wrote in message 
news:web.4a8859323e39793b37d670520@news.povray.org...
> "gil" <nomail@nomail> wrote:
>> Having a requirement for ropes in my project, I sprang with delight on 
>> the Rope
>> macros. However, whether I use the supplied rope.pov, or incorporate the
>> examples in my own pov file, the ropes are almost invisible. On close
>> inspection, they appear to be composed of coloured flecks, which may be 
>> the
>> fibre highlights, but the substance of the ropes appears transparent. I 
>> am
>> using povRay 3.6.
>>

It's worth checking the max_trace_level. If you're getting the message 
"max_trace_level exceeded" in the message stream then it's that. If it's 
that then adding:
  global_settings { max_trace_level 10}
into the scene file should fix it.

In 3.6 it requires an increased max_trace_level if Rope_ShowFibres is set to 
1 (which is the default). In 3.7 it doesn't. This is because this option 
adds a sort of semi-transparent shell around the outside of the rope with 
the fibre texture on it. In 3.6 this is counted as multiple additional trace 
levels, but it doesn't get counted in 3.7.

Regards,
Chris B.


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From: gil
Subject: Re: Rope macros
Date: 17 Aug 2009 00:15:00
Message: <web.4a88a0e23e39793b4c5582dd0@news.povray.org>
"Chris B" <nom### [at] nomailcom> wrote:
>
> It's worth checking the max_trace_level. If you're getting the message
> "max_trace_level exceeded" in the message stream then it's that. If it's
> that then adding:
>   global_settings { max_trace_level 10}
> into the scene file should fix it.
>
> In 3.6 it requires an increased max_trace_level if Rope_ShowFibres is set to
> 1 (which is the default). In 3.7 it doesn't. This is because this option
> adds a sort of semi-transparent shell around the outside of the rope with
> the fibre texture on it. In 3.6 this is counted as multiple additional trace
> levels, but it doesn't get counted in 3.7.
>
> Regards,
> Chris B.


Thanks a lot, both. It was the max_trace_level. I'm not used to povray
completing the render if there's something amiss in the messages, though I'd
probably still not have been able to figure out what to do if I had checked. So
now my Chinese junk can actually have rigging!

Regards.

Gil


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From: Chris B
Subject: Re: Rope macros
Date: 17 Aug 2009 05:35:52
Message: <4a88ec38@news.povray.org>
"gil" <nomail@nomail> wrote in message 
news:web.4a88a0e23e39793b4c5582dd0@news.povray.org...
> "Chris B" <nom### [at] nomailcom> wrote:
>>
>> It's worth checking the max_trace_level. If you're getting the message
>> "max_trace_level exceeded" in the message stream then it's that. If it's
>> that then adding:
>>   global_settings { max_trace_level 10}
>> into the scene file should fix it.
>>
>> In 3.6 it requires an increased max_trace_level if Rope_ShowFibres is set 
>> to
>> 1 (which is the default). In 3.7 it doesn't. This is because this option
>> adds a sort of semi-transparent shell around the outside of the rope with
>> the fibre texture on it. In 3.6 this is counted as multiple additional 
>> trace
>> levels, but it doesn't get counted in 3.7.
>
> Thanks a lot, both. It was the max_trace_level.

If you're using long bits of rope that aren't very close to the camera I'd 
recommend setting Rope_ShowFibres to 0 for those ropes because the 
transparency used to display the fibres has a big impact on render times and 
memory use. You only need Rope_ShowFibres set to 1 for those bits of rope 
that are close enough to the camera for the fibres to be visible and someone 
did comment that they thought the ropes looked better without the fibres 
anyway.

Certainly for test renders it's better to set Rope_ShowFibres to 0.

> So now my Chinese junk can actually have rigging!

That sounds terrific. I'd love to see how it looks when it's complete.

Regards,
Chris B.


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From: gil
Subject: Re: Rope macros
Date: 17 Aug 2009 08:35:01
Message: <web.4a8915473e39793b4c5582dd0@news.povray.org>
"Chris B" <nom### [at] nomailcom> wrote:

> If you're using long bits of rope that aren't very close to the camera I'd
> recommend setting Rope_ShowFibres to 0

OK. There will be a variety of views, so I'll tune it.

> > So now my Chinese junk can actually have rigging!
>
> That sounds terrific. I'd love to see how it looks when it's complete.
>
> Regards,
> Chris B.

Don't expect too much! The images are for a game, rather than for IRTC!

I've got a game blog at
http://amazonsystems.blogspot.com/ but development is glacially slow!

Regards.

Gil


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From: Cor
Subject: Re: Rope macros
Date: 27 Apr 2011 14:00:00
Message: <web.4db820cf3e39793b55f784c20@news.povray.org>
I have another question about the rope macro:
Is it possible to create a rope composed of a different number of strands than
3?
Two twisted strands for example?


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