On 08.08.2017 21:30, Kenneth wrote:
> Another view. No fog this time, but with radiosity (using the defaults, with
> brightness .6. I haven't yet worked out the best rad settings for this kind of
> scene... OR for an animated moving-camera version, which is even more
> demanding.)
> 
> No new changes yet, just more buildings (2500 for this render.) And I'm up to 19
> different window/facade image_maps now (and their respective window-reflection
> 'hold-out' mattes.)
> 
> The random heights of the buildings-- the number of stories (storeys?)-- is
> controlled with this...
> 
>          ceil(2 + 40*pow(rand(PP),4))
> 
> .... so there are a minimum of 3 (because of the way rand works-- it never goes
> to 0.0) and a max of 42, I think. I added the exponent to reduce the number of
> really tall buildings... which actually wipes out many of the mid-size scales as
> well. But it's fun to play around with.
> 
NIIICCEEEE. But dead, too.

Random add trees to the edges of the walk ways, and also street lights
(on/off). Add also randomly various shop types to the bottom of the
buildings, some or many with fluorescent neon light. Even some buildings
might feature some green on their roof, or swimming pools. Make the
streets darker, add white or even yellow markings. Some buildings should
have full glass surfaces (reflective) with exception of the edges. Some
buildings could have a slight change in angle along their vertical axis,
to give some accent and create triangular or diagonal spaces at their
base. Maybe, the taller buildings should be clustered together mainly in
the middle of the town, or along some roads, but not all over. At the
moment, their distribution is too homogeneous, I think. Hmmm, cars?

This is not meant as critique, but as further suggestions to support
your great macro! i really like it!

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Even an occasional empty slot, with a park, or playground, or small
houses, or gardens, or a public bath. Metro entrances, yes. A huge,
over-sized orange Trump statue - well, maybe not, forget that one. let
it be Obama. ;-)

Low restaurants, drive-ins, gas stations, Burger Kings, MacDonalds, Wendy's
.

:-D

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Sven Littkowski <I### [at] SvenLittkowskiname> wrote:
> A huge,
> over-sized orange Trump statue - well, maybe not, forget that one. let
> it be Obama. ;-)

I'd say that at this point, it ought to be of a Founder or of Cicero.

Bread and circuses do not last forever.

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Sven Littkowski <I### [at] SvenLittkowskiname> wrote:
>
> NIIICCEEEE. But dead, too.

Thanks. And I agree; it needs some 'city life' of some kind (not necessarily
tiny people.) Some automobile traffic is my first thought (probably just 'Yellow
Cabs' to start-- those constitute the main traffic in New York City, BY FAR.
Only the most stout-hearted people drive their own cars there!) My own concept
of this city is basically a NYC-type place: congested, busy, kind of old, and
not much greenery at all (except for Central Park there).
>
> Add also randomly various shop types to the bottom of the
> buildings, some or many with fluorescent neon light.

Adding 'ground floors' to the buildings is definitely on my list. The neon-light
marquees are a good idea as well; I hadn't thought of that. Although, for a
night-time scene-- to show such lighting effects-- I think I would need to
change quite a bit of my scene code; I didn't design the scene with that in
mind. But it's not impossible! ;-) I *would* like to see the city lit-up at
night. (The last time I was in NYC, I took some night-time photos out of my
upper-floor hotel window, of the surrounding skyscraper buildings. They look
really magical.)

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Am 05.08.2017 um 01:34 schrieb Kenneth:
> A couple more views...
> 
> Forgot to mention that I'm still working on the rooftop 'junk' (obviously!)

"Greebles" is the technical term.

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Am 05.08.2017 um 04:12 schrieb Kenneth:
> I just noticed something strange about the PNG images I posted: When I look at
> the small *preview* images here in my post (using the latest version of
> Firefox), they look correct: identical to how they appear on my own machine,
> when viewed in either Photoshop or the Windows Photo Viewer. (BTW, I
> post-processed the images in PS, but only to combine two renders into one post.)
> 
> But when I click on the image previews here-- and the higher-resolution versions
> appear-- the gamma of the images isn't correct! They look darker, with more
> contrast.
> 
> Does anyone else notice this? Right now, I have no idea what's going on, or why
> they appear differently on the same website.
> 
> Honestly, I simply don't trust PNG images to show up consistently or correctly,
> anywhere! :-(  I should have posted them as jpegs.

Actually, it's the PNG images that should generally be considered more
trustworthy, as it is virtually the only image file format that includes
gamma handling right in its specification.

My bet is that you instead have a wonky post-processing workflow, as
your PNG file is seriously odd: The `gAMA` chunk in your PNG file claims
that the file was encoded with a gamma of 0.22727 = 1/4.4 (or
"pre-corrected for a display gamma of 4.4", as it would be called in
other file formats), rather than the typical 0.45455 = 1/2.2; I suspect
that `gAMA` chunk is outright wrong.


For the JPEG file format, as far as gamma goes there's only a W3C
recommendation for use on the internet. The file format itself is
blissfully unaware of gamma. So you just have to pray that the target
system /happens/ to interpret them in the way you intended them to be
interpreted.

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Am 05.08.2017 um 06:28 schrieb Kenneth:
> "Kenneth" <kdw### [at] gmailcom> wrote:
>> One more image test, again for my own purposes: This PNG is *directly* from
>> POV-Ray (and NOT post-processed in Photoshop.) If it shows up correctly here
>> both as a small preview AND as the larger hi-rez image, then the problem will be
>> in my use of Photoshop, for some strange reason. An interesting experiment...
> 
> Confirmed(!) THIS PNG image looks correct to me--both the small preview as
> well as the larger hi-rez version, when clicking on the preview.

... and this one carries not only a `gAMA` chunk indicating an encoding
gamma of 1/2.2, but also a `sRGB` chunk indicating that in fact the
encoding doesn't use a gamma-law function but rather the sRGB transfer
function.

> This is indeed strange-- but at least I now have a clue as to what might be
> going on, within Photoshop (and how it treats POV-Ray-generated PNG
> renders--possibly changing their gamma when I certainly wasn't expecting that.)
> I need to test this further.
> 
> However...this does NOT explain the difference in appearance here of my
> originally posted PNG's-- the previews vs. the hi-rez versions. The only
> possible explanation I can come up with is that the newsgroup 'previews' are at
> one gamma setting, while the hi-rez versions are shown with a different setting.
> Sounds a bit crazy, I know...

The previews are most certainly generated without worrying too much
about gamma, effectively generating a JPEG image gamma pre-corrected for
whatever would have been the decoding gamma of the PNG file (4.4 in your
case).

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Am 05.08.2017 um 21:29 schrieb Kenneth:

> I also downloaded my own original PNG image post (the one shown in these
> screenshots), and it appears correct in *all* of my various image-viewer apps,
> no gamma change.

Then you should ditch all your various image-viewer apps, as they all
seem to disregard the PNG file specification regarding gamma.

Get LILYsoft's IC, which is the best image viewer/converter for Windows
I've seen so far. OpenEXR and Radiance HDR support included, and written
by POV-Ray community member "Ive".

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Am 05.08.2017 um 23:27 schrieb Kenneth:

> SO... it seems that my use of Photoshop-- at its *typical* gamma setting of
> 2.2-- was introducing a gamma change into the POV-Ray PNG image. I have aways
> assumed 2.2 to be the correct gamma in PS, for any/all PNG images that I've
> downloaded from the 'net, and even for Photoshop-created PNG images. But it's
> NOT correct for post-processing a POV-Ray PNG render: a PS gamma of 1.0 is
> necessary (at least for both of the newsgroup's two preview sizes to show up
> correctly!) So, *something* is amiss somewhere-- either a flaw in my version of
> Photoshop, OR in how the newsgroups treat preview images.

Have you made your display gamma known to Photoshop?
(And what version are you using anyway?)

> By the way, these are my POV-Ray render settings:
> A) assumed_gamma 1.0 in the scene file
> B) Display_Gamma of 'srgb' in my .ini file
> C) File_Gamma of 'srgb' in my .ini file

Good boy. That should be exactly right... provided you have set up your
display and Windows to match sRGB gamma.

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Am 09.08.2017 um 03:30 schrieb Kenneth:
> Another view. No fog this time, but with radiosity (using the defaults, with
> brightness .6. I haven't yet worked out the best rad settings for this kind of
> scene... OR for an animated moving-camera version, which is even more
> demanding.)

Radiosity brightness .6 is unrealistic. If brightness 1.0 gives you too
bright indirectly-lit areas, your pigment*diffuse values are too high.

The only physically legitimate reason for using brightness is to set it
/above/ 1.0 when using a low recursion limit, to counteract the
resulting dimming in comparison to high recursion limit renders.

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