Mike Horvath <mik### [at] gmailcom> wrote:
> On 1/19/2016 11:08 AM, clipka wrote:
> > Am 19.01.2016 um 02:48 schrieb Mike Horvath:
> >> Here's my latest (incomplete) render. However, I don't understand why
> >> the planet in the background is so bright compared to the last render.
> >> Can anyone explain this? Is it the area light causing this or the
> >> reflections? I'm using the same area light as in the last render and I
> >> don't understand why the planet appears to be extra lit. Thanks.
> >
> > Did you make sure that the light properly falls off with distance?
> >
>
> What values would you recommend? It is a linear area light.

Presuming the area light is supposed to simulate a structure somewhat akin to a
long cylinder, I would set fade_distance to the radius of that structure; to get
the proper behaviour along the length of the area light, I would suggest using
area_illumination.

For realism, fade_power should always be 2. Note that you may have to
significantly increase the light source's brightness.

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Le 16-01-25 04:01, Sven Littkowski a écrit :
> Nice inside landscaping. Shouldn't all building be of the same shape, in
> regards to ensure all over the cylinder is the same mass distribution?
> Otherwise, mass unbalance might cause problems while spinning. I don't
> mean the shape of buildings from back to front, but beside each other.
>

You just need the building to be similar across the axis. Side by side, 
it don't mather.
Also, you can have a small building containing huigh mass cargo, and 
large ones used by peoples that have about the same overall mass.
Finaly, there is probably a network of balast "underground" to help 
balancing the whole thing.



Alain

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On 1/25/2016 4:01 AM, Sven Littkowski wrote:
> Nice inside landscaping. Shouldn't all building be of the same shape, in
> regards to ensure all over the cylinder is the same mass distribution?
> Otherwise, mass unbalance might cause problems while spinning. I don't
> mean the shape of buildings from back to front, but beside each other.
>

I think the scene would look less interesting if the buildings are the 
same. Anyway, if I were to make changes, I would go in the *other* 
direction. I.e. make the scene look even *more* organic.


Mike

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On 1/25/2016 9:02 AM, clipka wrote:
> Presuming the area light is supposed to simulate a structure somewhat akin to a
> long cylinder, I would set fade_distance to the radius of that structure; to get
> the proper behaviour along the length of the area light, I would suggest using
> area_illumination.

I experimented with fade_distance by setting it to the radius of the 
lamp object, but it makes the scene too dark.


>
> For realism, fade_power should always be 2. Note that you may have to
> significantly increase the light source's brightness.
>
>

Good tip, thanks.



Mike

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On 1/25/2016 4:02 AM, Sven Littkowski wrote:
> How did you make the trees? I could use that technology for some of my
> scenes, too. :-)
>

It may be TomTree.

http://tkgate.sourcearchive.com/documentation/2.0~b8/TOMTREE_8inc-source.html

I don't recall for sure.


Mike

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Mike Horvath <mik### [at] gmailcom> wrote:
> On 1/25/2016 9:02 AM, clipka wrote:
> > Presuming the area light is supposed to simulate a structure somewhat akin to a
> > long cylinder, I would set fade_distance to the radius of that structure; to get
> > the proper behaviour along the length of the area light, I would suggest using
> > area_illumination.
>
> I experimented with fade_distance by setting it to the radius of the
> lamp object, but it makes the scene too dark.
>
> > For realism, fade_power should always be 2. Note that you may have to
> > significantly increase the light source's brightness.

Multiply the light source's color by (1 + pow (D / R, 2)) / 2, where R is the
fade_distance, and D is the radius of the colony interior.

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Question: Should the density of the gas in the habitat area be 
significantly lower around the central axis than toward the outer edges 
of the cylinder? Or is it safe to ignore such a gradient?


Mike

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On 1/25/2016 3:20 PM, Cousin Ricky wrote:
> Mike Horvath <mik### [at] gmailcom> wrote:
>> On 1/25/2016 9:02 AM, clipka wrote:
>>> Presuming the area light is supposed to simulate a structure somewhat akin to a
>>> long cylinder, I would set fade_distance to the radius of that structure; to get
>>> the proper behaviour along the length of the area light, I would suggest using
>>> area_illumination.
>>
>> I experimented with fade_distance by setting it to the radius of the
>> lamp object, but it makes the scene too dark.
>>
>>> For realism, fade_power should always be 2. Note that you may have to
>>> significantly increase the light source's brightness.
>
> Multiply the light source's color by (1 + pow (D / R, 2)) / 2, where R is the
> fade_distance, and D is the radius of the colony interior.
>
>


That worked, thank you!


Mike

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On 1/25/2016 7:27 PM, Alain wrote:
> Finaly, there is probably a network of balast "underground" to help
> balancing the whole thing.

I would say more than probably. On ships and semi-submersible oil rigs. 
The balast has to be adjusted whenever the cargo changes.

-- 

Regards
     Stephen

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Am 25.01.2016 um 23:11 schrieb Mike Horvath:
> Question: Should the density of the gas in the habitat area be
> significantly lower around the central axis than toward the outer edges
> of the cylinder? Or is it safe to ignore such a gradient?

Given the comparatively small size of the habitat, it should be negligible.

Presuming both artificial gravitation and ground level air pressure to
be similar to conditions on Earth, you'd also get a somewhat similar
atmospheric density gradient. (It would even be less pronounced than on
Earth, as the artificial gravitation would fall off much faster with
increase in height above ground.)

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