[Radiance-general] partly covered source

Jan Wienold jan.wienold at ise.fraunhofer.de
Tue Jul 24 14:08:57 PDT 2012


Hi Giulio,

thanks!

Both solutions are a question of calculation time... but I use the 
second way now to be on the safe side (calculation of image) - even it 
takes me much longer...For the evaluation I use evalglare, is pretty 
simple to use for such cases.

For reflections I already did it in that way and I used a modified 
version of evalglare (will put it online soon) to calculate the angle 
between different glare sources (in that case between reflection and 
sun), too. The only disadvantage is the long calculation time of several 
days (1 image (ab0)+evaluation takes 6 sec -> 2.5 days on a single core 
for one point..and I have 33 points and two geometries...).

Jan

On 07/24/2012 10:05 PM, giulio antonutto wrote:
> Alternatively there is another option.
> derive illuminance from a standard image.
> so:
> render what a calculation point sees in view -h mode
> then write a script to process the luminance data and the angular location alongside the solid angle of a single pixel.
> the total contribution, the sum, would be the total illuminance, regardless of any subdivision etc.
> but it takes 1 image for each point and you may need to investigate the resolution required to capture all sources (if small)…
> we have done this before (Andy,remember?) and it works quite well.
> In fact the method can be extended to calculate reflections and caustics...
> Good luck with the judge!
> G
>
>
>
> On 24 Jul 2012, at 20:50, Jan Wienold wrote:
>
>> Hi Giulio, hi all,
>>
>> unfortunately it doesn't work out safely. In total I have many, many cases to look at (in total 40000 timesteps x 33 points x 2geometries) and there are still many cases, when rtrace doesn't catch the sun.
>> Since these are calculations for an expertise, which is used for a trial, I have to be absolutely sure not to miss any case...
>>
>> Is there any idea except calculating images ? Source subdivisions are unfortunately not possible when "source" is used...
>>
>> Thanks!
>>
>> Jan
>>
>>
>>
>> On 07/24/2012 02:13 AM, Jan Wienold wrote:
>>> hi giulio,
>>>
>>> Yes!
>>> The use of -dj helped, but only if I use also the -u option. Otherwise I still get randomized zero values, also if I change -ds.
>>>
>>> thanks!
>>>
>>> jan
>>>
>>>
>>>
>>>
>>> On 07/24/2012 01:35 AM, giulio antonutto wrote:
>>>> Jan,
>>>> maybe you can fix it with -dj and oversampling?
>>>> G
>>>>
>>>> On 24 Jul 2012, at 00:03, Jan Wienold wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>> I just encountered a strange different behavior between rtrace and rpict:
>>>>> If the sun ( using "source") is  covered in large parts (in that case more than half) I can still "see" the uncovered parts in the image (=>this is what I expect). In case I calculate at the same point and in the same direction the illuminance with rtrace -I, I get zero contribution.  Is just the center of the source description tested in that case? Any solution for this for rtrace?
>>>>> I just look for the sun, no sky description and use only direct calculation (-ab 0) .
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Jan
>>>>>
>>>>>
>>>>>
>>>>> -- 
>>>>> Dr.-Ing. Jan Wienold
>>>>> Head of Team Passive Systems and Daylighting
>>>>> Fraunhofer-Institut für Solare Energiesysteme
>>>>> Thermal Systems and Buildings
>>>>> Heidenhofstr. 2, 79110 Freiburg, Germany
>>>>> Phone: +49(0)761 4588 5133 Fax:+49(0)761 4588 9133
>>>>> jan.wienold at ise.fraunhofer.de
>>>>> http://www.ise.fraunhofer.de
>>>>>
>>>>> In office:
>>>>> Mo,Tue: 8:30-18:00
>>>>> We,Thu: 8:30-16:00
>>>>> Fr:  8:30-15:30
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Radiance-general mailing list
>>>>> Radiance-general at radiance-online.org
>>>>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>>>> _______________________________________________
>>>> Radiance-general mailing list
>>>> Radiance-general at radiance-online.org
>>>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>>>
>>
>> -- 
>> Dr.-Ing. Jan Wienold
>> Head of Team Passive Systems and Daylighting
>> Fraunhofer-Institut für Solare Energiesysteme
>> Thermal Systems and Buildings
>> Heidenhofstr. 2, 79110 Freiburg, Germany
>> Phone: +49(0)761 4588 5133 Fax:+49(0)761 4588 9133
>> jan.wienold at ise.fraunhofer.de
>> http://www.ise.fraunhofer.de
>>
>> In office:
>> Mo,Tue: 8:30-18:00
>> We,Thu: 8:30-16:00
>> Fr:  8:30-15:30
>>
>>
>> _______________________________________________
>> Radiance-general mailing list
>> Radiance-general at radiance-online.org
>> http://www.radiance-online.org/mailman/listinfo/radiance-general
>
> _______________________________________________
> Radiance-general mailing list
> Radiance-general at radiance-online.org
> http://www.radiance-online.org/mailman/listinfo/radiance-general


-- 
Dr.-Ing. Jan Wienold
Head of Team Passive Systems and Daylighting
Fraunhofer-Institut für Solare Energiesysteme
Thermal Systems and Buildings
Heidenhofstr. 2, 79110 Freiburg, Germany
Phone: +49(0)761 4588 5133 Fax:+49(0)761 4588 9133
jan.wienold at ise.fraunhofer.de
http://www.ise.fraunhofer.de

In office:
Mo,Tue: 8:30-18:00
We,Thu: 8:30-16:00
Fr:  8:30-15:30




More information about the Radiance-general mailing list