"clipka" <nomail@nomail> wrote:
> "triple_r" <nomail@nomail> wrote:
> > If you didn't already, I covered all the gaps in the door with transparent
> > triangular portals when I tried this scene.  This forces rays to be shot at the
> > gaps, rather than hitting by chance.  In other words, unless this was a snapshot
> > after about eight seconds of rendering, it's gonna be a while.
>
> That would help smoothing the "gaps" quickly - but would it also help with the
> "stars" on the walls?

Consider how path-tracing works.  It's like adding diffuse reflection to all
surfaces.  First, a ray is sent out at a given pixel.  When that ray hits
something, it spawns more rays.  This happens recursively, and if one of the
paths ends up at a light source, that color is transferred forward to the
pixel.  If the light sources are too small, 99.999% of the rays are never going
to find a light source.  The 0.001% that do find a gap in the door after a
bounce or two result in the "stars."  However, if you use a portal, then you're
saying that you know in advance where the light is, so we'll always send a ray
in that direction, just in case.  Not perfect, but it makes a huge difference.

 - Ricky

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> Consider how path-tracing works.  It's like adding diffuse reflection to all
> surfaces.  First, a ray is sent out at a given pixel.  When that ray hits
> something, it spawns more rays.  This happens recursively, and if one of the
> paths ends up at a light source, that color is transferred forward to the
> pixel.  If the light sources are too small, 99.999% of the rays are never going
> to find a light source.  The 0.001% that do find a gap in the door after a
> bounce or two result in the "stars."  However, if you use a portal, then you're
> saying that you know in advance where the light is, so we'll always send a ray
> in that direction, just in case.  Not perfect, but it makes a huge difference.

I didn't yet manage to put that to good use for my scene; all I got was a
tremendous slowdown per pass, less "stars", but also less visibility of the
door.

Then, Windows crashed again. Looks like it just needs its daily reboot.

I'd love to give it a try on Linux, but I can't seem to get MCPov compiled
properly: icrc gags on the source code, and gcc gives me an executable that
just segfaults. Using Debian "etch" 4.0r5 for AMD64.

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"clipka" <nomail@nomail> wrote:
> Although being by no means what I was aiming at, this WIP is one of those that
> have a beauty in their own right...
>
> This is a snapshot of a work that's currently in the progress of being rendered
> with MCPov. What is it? A door in the night sky? A stargate, so to speak? In any
> case, it seems to lead to a place of imagination...

Please answer the door, there is a knock...

--
Carlo

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clipka wrote:
> "Mike Hough" <nos### [at] nospamcom> wrote:
>> How long has it been running?
> 
> Not so much back then; half an hour maybe...?

Half an hour and ONLY those dots?

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Nicolas Alvarez <nic### [at] gmailcom> wrote:
> clipka wrote:
> > "Mike Hough" <nos### [at] nospamcom> wrote:
> >> How long has it been running?
> >
> > Not so much back then; half an hour maybe...?
>
> Half an hour and ONLY those dots?

Eight days, and ONLY this comment? ;)

Hey, That was my first attempt at rendering *anything* with MCPov - and I guess
I didn't choose the easiest scene...

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