Hi all, Happy Holidays!

I had two days of unexpected downtime earlier this week and made the "mistake"
of firing up POV-Ray for the first time in almost a year! As always, one thing
led to another and down the rabbit hole I went...

I wanted to make a photorealistic CG scene that merged seamlessly (more or less)
with an HDR environment. This is something that I've done before, but I wanted
to try and get a more photorealistic end result than my previous images have
achieved.

Inspired by an actual sculpture I recently saw outside a local art museum I
started modeling and coding. A few hundred iterations later I ended up with this
image: a spherical shell assembled from 16,500 glass shards balanced atop a
weathered granite boulder, displayed as a sculptural art piece in the
internationally famous POV-Ray Museum of Art's digital outer courtyard.

The sphere was created using a single "shard" object (a superellipsoid) that was
instanced and transformed via nested U and V loops using the standard spherical
parametric equations. Each glass shard is unique, having randomized scaling,
rotation and pigment color/interior fade color.

The granite boulder is a fairly simple UV mapped polygon model that was
displaced by PoseRay (via a 4K image map texture and adaptive subdivision) and
exported as a 105K triangle Mesh3 object. All of the rocks surrounding the base
disc of bricks, along with the jumbled wall of rocks in the right-hand
background, are instances of this same object with random rotations and scales.

The ground is a simple Y-plane textured with image mapped stone blocks. Two area
lights provide direct lighting and soft shadows, while the overall environment
is a 4K EXR sphere that provides both indirect lighting and background image.
Camera focal-blur ties the image-mapped plane and background EXR sphere together
cohesively.

The object creation and overall layout of this scene was done in just a few
hours but, as usual, I spent 80% of the total time tweaking lighting and
texturing. In the end I rendered the image at 4K and then scaled down to HD to
try and get more pristine antialiasing while minimizing focal-blur sample noise
and pixelation of the EXR background (which is pretty noticeable at 4K - I guess
I'll need to start using 8K image maps for stuff like this).

Here's a low-res comp of the untextured scene objects versus textured final
render.

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Preview of image 'rwmglasssculpture_textured-untextured.jpg'

"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> Here's a low-res comp of the untextured scene objects versus textured final
> render.

Here's the HD resized final render.

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Attachments:
Download 'rwmglasssculpture.jpg' (1399 KB)

Preview of image 'rwmglasssculpture.jpg'

"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> Here's the HD resized final render.

Here's a detail shot of the bricks disc and border rocks

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Download 'rwmglasssculpture_detail1.jpg' (791 KB)

Preview of image 'rwmglasssculpture_detail1.jpg'

Here's a detail shot of the glass

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Download 'rwmglasssculpture_detail2.jpg' (1094 KB)

Preview of image 'rwmglasssculpture_detail2.jpg'

Here's a detail shot of the boulder

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Download 'rwmglasssculpture_detail3.jpg' (1123 KB)

Preview of image 'rwmglasssculpture_detail3.jpg'

Op 10/12/2022 om 01:56 schreef Robert McGregor:
> Hi all, Happy Holidays!
> 
> I had two days of unexpected downtime earlier this week and made the "mistake"
> of firing up POV-Ray for the first time in almost a year! As always, one thing
> led to another and down the rabbit hole I went...
> 
> I wanted to make a photorealistic CG scene that merged seamlessly (more or less)
> with an HDR environment. This is something that I've done before, but I wanted
> to try and get a more photorealistic end result than my previous images have
> achieved.
> 

Hi Robert!
This is a most excellent work (again). I guess that you have pretty well 
achieved your primary goal: merging the HDR environment with the CG 
scene. Knowing what you have done and scrutinising the final render, it 
is very hard to see where both blend together. An unprepared watcher 
would be unaware of the blend. Very well done.

I love the shards sculpture. How would it look backlighted? or at night 
with some (discrete) illumination inside?

The rock is spot on. It stresses the need to use high-resolution image 
maps for this kind of work indeed.

And I acknowledge your detailed and careful explanation of the scene 
building.

Welcome back btw. You should do more of this stuff. :-)
-- 
Thomas

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Robert,

Great integration, beautiful rocks and scene.

The initial response i thought of "did you forgot the photon switch?"

I love the glass object, but sadly its glassiness also makes it look kind of
flat. The self shadowing gets lost. Compare the black & white image with the
colour one.

The half colour, half b&W image is very intriguing. As if the sphere has a
transition from stone to glass.

To give the glass object some more self shadowing, maybe an absorbing media
inside would help. Or photons.

ingo

"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> Hi all, Happy Holidays!
>
> I had two days of unexpected downtime earlier this week and made the "mistake"
> of firing up POV-Ray for the first time in almost a year! As always, one thing
> led to another and down the rabbit hole I went...

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Op 10-12-2022 om 08:34 schreef Thomas de Groot:
> The rock is spot on. It stresses the need to use high-resolution image 
> maps for this kind of work indeed.
> 
I forgot: Maybe add a normal_map based on the image map to add some 
micro-structure/roughness to the rock surface?

-- 
Thomas

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"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> "Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> > Here's a low-res comp of the untextured scene objects versus textured final
> > render.
>
> Here's the HD resized final render.

That's pretty cool!

Those rocks are _extremely_ realistic looking.  Presumably there is no visible
seam on the surface?

I'd say that the environment map is --- too blurry, and it makes everything else
which is sharp - "float".

Maybe if you can sharpen the ground, or overlay a fading mimic of the paving so
that the sharp-to blurry transition mimics focal blur, that would help.

Perhaps some intermediate object behind the ball and the blurry background would
help ease the transition as well.

Also, maybe adding a bit of real focal blur to soften the ring behind the
center.

That sphere is cool, but the closeups look better than the overall sphere.
Maybe increase the chip size or make it a little more sparse to get that glass
look.  From far away it all just sort of blend in together, and you lose the
amazing texture that you've highlighted in the closeup.

Nice project to take up to get you back into the addiction   :D

- BW

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I would say you are spot on, I am having trouble working out which parts are HDR
background and which are rendered. At first I thought it was just the
plane/rocks/sphere until I spotted the povray logo on the building so now I
assume the trees next to the steps are also part of your scene? If so then good
job matching them to the HDR trees also to add to the illusion.

The glass sculpture is great, I can only imagine how slowly it renders ;-)

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