Cousin Ricky <ric### [at] yahoocom> wrote:
> On 2021-12-15 5:10 PM (-4), Chris R wrote:
> >
> > Looking at the picture in detail, I was unhappy with the way the puddle melting
> > off of the snowman looked.  ...
>
> I didn't comment on the snowman before, because I didn't know if you
> wanted it to be real snow. But now that I see that it's melting, I have
> a couple of suggestions.
>
> First off, the diffuse value needs to be higher, close to 1.0.  And if
> you are *not* using radiosity, the ambient value needs to be scaled up
> proportionately.
>
> Second, snow really needs SSLT.  Of course, this will slow down the
> render even more.  If you prefer to finish rendering by February, you
> can cheat by adding a bit of emission to the snow in lieu of SSLT; I
> once abused the ambient keyword this way to get a subsurface effect on
> some beach balls.  If you cheat in this manner, then you may have to
> take the diffuse below 1.0 to compensate for the "glow."
>
> Otherwise, the scene looks great!

Thanks for the suggestions.  I keep waffling on whether to make the snow more
realistic or not.  The scene is a bunch of ornaments, so the melting snowman is
meant to be a bit of humor, but I had also considered making him a real snowman
who just happens to have wandered into the scene.  I'll try some of your
suggestions as I can see other uses for having a good model for snow.

-- Chris R

Post a reply to this message

On 16/12/2021 5:10 am, Chris R wrote:
> "Chris R" <car### [at] comcastnet> wrote:
>> A bit of a work-in-progress, but far enough along to show.  This took about
>> 4-days to render without any camera blur, which I'd like to add at some point.
>>
>> There are a few more ornaments/elements I'd like to add in for interest.  I'll
>> probably have to play with the lights a bit or it will never finish rendering
>> before the holidays are over... :-;
>>
>> -- Chris Rath
> 
> Looking at the picture in detail, I was unhappy with the way the puddle melting
> off of the snowman looked.  So, in true geek fashion, I looked up the theory
> behind surface tension of water when puddling on a solid surface, and rewrote
> the macro that generates the puddle to take all of that into account.
> 
> Here is a closeup test view of the snowman with the new puddle, with which I am
> quite happy now.  I will probably have to update the scene to make the puddle
> more obvious in the full scene, because it's kind of hard to notice now.
> 
> Of course, now I'm unhappy with the scarf, so I'll be working on that next...
> 
> -- Chris Rath

Here is my take on a melting snowman:
<https://youtu.be/puo_eVkz0gY>

(Work in progress)
(In TikTok format)

m@

Post a reply to this message

"m@b" <sai### [at] googlemailcom> wrote:
> On 16/12/2021 5:10 am, Chris R wrote:
> > "Chris R" <car### [at] comcastnet> wrote:
> >> A bit of a work-in-progress, but far enough along to show.  This took about
> >> 4-days to render without any camera blur, which I'd like to add at some point.
> >>
> >> There are a few more ornaments/elements I'd like to add in for interest.  I'll
> >> probably have to play with the lights a bit or it will never finish rendering
> >> before the holidays are over... :-;
> >>
> >> -- Chris Rath
> >
> > Looking at the picture in detail, I was unhappy with the way the puddle melting
> > off of the snowman looked.  So, in true geek fashion, I looked up the theory
> > behind surface tension of water when puddling on a solid surface, and rewrote
> > the macro that generates the puddle to take all of that into account.
> >
> > Here is a closeup test view of the snowman with the new puddle, with which I am
> > quite happy now.  I will probably have to update the scene to make the puddle
> > more obvious in the full scene, because it's kind of hard to notice now.
> >
> > Of course, now I'm unhappy with the scarf, so I'll be working on that next...
> >
> > -- Chris Rath
>
> Here is my take on a melting snowman:
> <https://youtu.be/puo_eVkz0gY>
>
> (Work in progress)
> (In TikTok format)
>
> m@

Nice!  I thought about doing an animation of my snowman melting, and having the
puddle grow as he does so.  However, it all renders so slowly that I'd have to
rent a big server farm to get all of the frames done in my lifetime...

Any particular tools you use to convert frames to movies?

-- Chris Rath

Post a reply to this message

Il 14/12/2021 22:49, Chris R ha scritto:
 > A bit of a work-in-progress, but far enough along to show.  This took 
about
 > 4-days to render without any camera blur, which I'd like to add at 
some point.
 >
 > There are a few more ornaments/elements I'd like to add in for 
interest.  I'll
 > probably have to play with the lights a bit or it will never finish 
rendering
 > before the holidays are over... :-;
 >
 > -- Chris Rath
 >

A beautiful light!

Merry Christmas!
Paolo

Post a reply to this message

"Chris R" <car### [at] comcastnet> wrote:
> Cousin Ricky <ric### [at] yahoocom> wrote:
> > On 2021-12-15 5:10 PM (-4), Chris R wrote:
> > >
> > > Looking at the picture in detail, I was unhappy with the way the puddle melting
> > > off of the snowman looked.  ...
> >
> > I didn't comment on the snowman before, because I didn't know if you
> > wanted it to be real snow. But now that I see that it's melting, I have
> > a couple of suggestions.
> >
> > First off, the diffuse value needs to be higher, close to 1.0.  And if
> > you are *not* using radiosity, the ambient value needs to be scaled up
> > proportionately.
> >
> > Second, snow really needs SSLT.  Of course, this will slow down the
> > render even more.  If you prefer to finish rendering by February, you
> > can cheat by adding a bit of emission to the snow in lieu of SSLT; I
> > once abused the ambient keyword this way to get a subsurface effect on
> > some beach balls.  If you cheat in this manner, then you may have to
> > take the diffuse below 1.0 to compensate for the "glow."
> >
> > Otherwise, the scene looks great!
>
> Thanks for the suggestions.  I keep waffling on whether to make the snow more
> realistic or not.  The scene is a bunch of ornaments, so the melting snowman is
> meant to be a bit of humor, but I had also considered making him a real snowman
> who just happens to have wandered into the scene.  I'll try some of your
> suggestions as I can see other uses for having a good model for snow.
>
> -- Chris R

I started playing around with subsurface in the finish for the snowballs.  After
fiddling with settings I could get some very convincing looking ice-balls, but
I'm not sure how to get it to look more like snow.

A few other things I noticed in my experiments:
 - Using subsurface dampens the effects of any normals in the texture pretty
dramatically.  This isn't too much of an issue since my snowballs are
isosurfaces and I can just translate the normals into perturbations on the
sphere shape.  I assume that's a known effect due to the subsurface algorithm,
it just surprised me.
 - There is an interaction between the diffuse setting in the finish and
subsurface.  I found if diffuse is too high, I get a very weird, reflective
surface.  I wonder if this is related to the caveats in the wiki about
zero-values in colors used for subsurface, or if it's some undocumented
interaction.

-- Chris R

Post a reply to this message

On 16/12/2021 10:12 pm, Chris R wrote:
> "m@b" <sai### [at] googlemailcom> wrote:
>> On 16/12/2021 5:10 am, Chris R wrote:
>>> "Chris R" <car### [at] comcastnet> wrote:
>>>> A bit of a work-in-progress, but far enough along to show.  This took about
>>>> 4-days to render without any camera blur, which I'd like to add at some point.
>>>>
>>>> There are a few more ornaments/elements I'd like to add in for interest.  I'll
>>>> probably have to play with the lights a bit or it will never finish rendering
>>>> before the holidays are over... :-;
>>>>
>>>> -- Chris Rath
>>>
>>> Looking at the picture in detail, I was unhappy with the way the puddle melting
>>> off of the snowman looked.  So, in true geek fashion, I looked up the theory
>>> behind surface tension of water when puddling on a solid surface, and rewrote
>>> the macro that generates the puddle to take all of that into account.
>>>
>>> Here is a closeup test view of the snowman with the new puddle, with which I am
>>> quite happy now.  I will probably have to update the scene to make the puddle
>>> more obvious in the full scene, because it's kind of hard to notice now.
>>>
>>> Of course, now I'm unhappy with the scarf, so I'll be working on that next...
>>>
>>> -- Chris Rath
>>
>> Here is my take on a melting snowman:
>> <https://youtu.be/puo_eVkz0gY>
>>
>> (Work in progress)
>> (In TikTok format)
>>
>> m@
> 
> Nice!  I thought about doing an animation of my snowman melting, and having the
> puddle grow as he does so.  However, it all renders so slowly that I'd have to
> rent a big server farm to get all of the frames done in my lifetime...
> 
> Any particular tools you use to convert frames to movies?
> 
> -- Chris Rath
> 
> 

<https://ffmpeg.org/>   is very versatile, you can call it as a shellout 
from POV-Ray.

m@

Post a reply to this message

"Chris R" <car### [at] comcastnet> wrote:
> "Chris R" <car### [at] comcastnet> wrote:
> > A bit of a work-in-progress, but far enough along to show.  This took about
> > 4-days to render without any camera blur, which I'd like to add at some point.
> >
> > There are a few more ornaments/elements I'd like to add in for interest.  I'll
> > probably have to play with the lights a bit or it will never finish rendering
> > before the holidays are over... :-;
> >
> > -- Chris Rath
>
> Looking at the picture in detail, I was unhappy with the way the puddle melting
> off of the snowman looked.  So, in true geek fashion, I looked up the theory
> behind surface tension of water when puddling on a solid surface, and rewrote
> the macro that generates the puddle to take all of that into account.
>
> Here is a closeup test view of the snowman with the new puddle, with which I am
> quite happy now.  I will probably have to update the scene to make the puddle
> more obvious in the full scene, because it's kind of hard to notice now.
>
> Of course, now I'm unhappy with the scarf, so I'll be working on that next...
>
> -- Chris Rath

Here's an updated version of the snowman using subsurface in the finish.  I
moved the normals into the isosurface itself, and changed the scale to make the
bumpy snow smaller, and then used a subsurface with a translucency of 0.1 and a
diffuse of 0.7.  It still looks like an ornament, but is fluffier, rather than
ceramic-looking.

I am rendering another version with a translucency of 0.5 that looks more like
real snow.  I'll post it when it finishes.

-- Chris R

Post a reply to this message

Attachments:
Download 'snowmen_sslt2.png' (746 KB)

Preview of image 'snowmen_sslt2.png'

"Chris R" <car### [at] comcastnet> wrote:
> "Chris R" <car### [at] comcastnet> wrote:
> > "Chris R" <car### [at] comcastnet> wrote:
> > > A bit of a work-in-progress, but far enough along to show.  This took about
> > > 4-days to render without any camera blur, which I'd like to add at some point.
> > >
> > > There are a few more ornaments/elements I'd like to add in for interest.  I'll
> > > probably have to play with the lights a bit or it will never finish rendering
> > > before the holidays are over... :-;
> > >
> > > -- Chris Rath
> >
> > Looking at the picture in detail, I was unhappy with the way the puddle melting
> > off of the snowman looked.  So, in true geek fashion, I looked up the theory
> > behind surface tension of water when puddling on a solid surface, and rewrote
> > the macro that generates the puddle to take all of that into account.
> >
> > Here is a closeup test view of the snowman with the new puddle, with which I am
> > quite happy now.  I will probably have to update the scene to make the puddle
> > more obvious in the full scene, because it's kind of hard to notice now.
> >
> > Of course, now I'm unhappy with the scarf, so I'll be working on that next...
> >
> > -- Chris Rath
>
> Here's an updated version of the snowman using subsurface in the finish.  I
> moved the normals into the isosurface itself, and changed the scale to make the
> bumpy snow smaller, and then used a subsurface with a translucency of 0.1 and a
> diffuse of 0.7.  It still looks like an ornament, but is fluffier, rather than
> ceramic-looking.
>
> I am rendering another version with a translucency of 0.5 that looks more like
> real snow.  I'll post it when it finishes.
>
> -- Chris R

And here's the snowier one...

-- Chris R

Post a reply to this message

Attachments:
Download 'snowmen.png' (743 KB)

Preview of image 'snowmen.png'

Op 18/12/2021 om 05:03 schreef Chris R:
> 
> And here's the snowier one...
> 
I think I prefer this one. To better show the translucency, put the 
light behind the snowman.

-- 
Thomas

Post a reply to this message

"Chris R" <car### [at] comcastnet> wrote:
> A bit of a work-in-progress, but far enough along to show.  This took about
> 4-days to render without any camera blur, which I'd like to add at some point.
>
> There are a few more ornaments/elements I'd like to add in for interest.  I'll
> probably have to play with the lights a bit or it will never finish rendering
> before the holidays are over... :-;
>
> -- Chris Rath

Hi Chris,

Nice and warm scene. I like the textures of the presents packaging, and the star
ornaments remember me of the ones I had fun to make every year as a child
(nostalgic mood triggered). The chains (?) holding them are barely visible, they
would surely benefit of being thicker. The last version of the snowman you
posted looks good, but aren't the dark spot a bit too dark ? The new puddle
looks good too. In the original scene it's quite hidden behind the lights. A
different composition there may help ? Also I thought the texture of the table
could be improved. To be honest I don't quite understand what kind of material
it is.

Merry Christmas to you too and to all the POV-Ray community !

Pascal

Post a reply to this message