A couple of weeks ago some posts here started me thinking about rendering some
sci-fi space scenes, so I started working on assets that would allow me to build
a variety of cool scenes.

I started off with a simple noise-based star field texture, along with an
accompanying alien moon.

Next, I used a parametric spherical spiral macro (that I recently posted) to
create the basis of an ancient alien artifact.

A dynamically generated 16-bit PNG function-pigment heightfield became an alien
landscape.

I knew I needed some humanoids for scale, so I found a free hi-res OBJ astronaut
model on the Internet. Using MeshLab I decimated the hi-res mesh polygons to an
acceptable level, then imported to Blender and built a simple astronaut pose
rig. As always, I converted to mesh2 via PoseRay for POV-Ray rendering.

Cheers,
Rob

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Here is the result of assembling my sci-fi assets into a scene, as astronauts
investigate an ancient alien artifact at sunrise on a distant world. The
material I used for the orange/glassy portion of the artifact was incredibly
slow to render, so it took almost two days.

As a post-processing step I also wrote a simple brightness mask scene file that
reads in an existing image and masks off (as black) areas that are below a
specified brightness threshold. A simple 5x5 Gaussian convolution matrix is then
iterated across the resulting masked image to blur the remaining pixels for a
simple glow effect (not sure if this is similar to what Sam Benge does for his

multi-pass rendering methods that I posted here a decade ago, the glow results
are then composited with the original image (e.g., the halo around the

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On 2/17/21 10:59 PM, Robert McGregor wrote:
> Here is the result of assembling my sci-fi assets into a scene, as astronauts
> investigate an ancient alien artifact at sunrise on a distant world. 
...

Cool. :-)

The hint of atmosphere in the star field - is that something added to 
the star field, added as fog or is it related to the added luminous bloom?

Bill P.

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Op 18/02/2021 om 04:59 schreef Robert McGregor:
> Here is the result of assembling my sci-fi assets into a scene, as astronauts
> investigate an ancient alien artifact at sunrise on a distant world. The
> material I used for the orange/glassy portion of the artifact was incredibly
> slow to render, so it took almost two days.
> 
> As a post-processing step I also wrote a simple brightness mask scene file that
> reads in an existing image and masks off (as black) areas that are below a
> specified brightness threshold. A simple 5x5 Gaussian convolution matrix is then
> iterated across the resulting masked image to blur the remaining pixels for a
> simple glow effect (not sure if this is similar to what Sam Benge does for his

> multi-pass rendering methods that I posted here a decade ago, the glow results
> are then composited with the original image (e.g., the halo around the

> 

Excellent! And Thanks for the detailed explanation; I shall note that 
carefully down for future study and use. The pose rig is particularly 
interesting for me. I have done some of this in Poser and there it is - 
not difficult - but demanding a close attention. How is this in Blender? 
more straightforward? Somehow, I guess it needs a close attention there too.

-- 
Thomas

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On 2/17/21 10:59 PM, Robert McGregor wrote:
> Here is the result of assembling my sci-fi assets into a scene, as astronauts
> investigate an ancient alien artifact at sunrise on a distant world. The
> material I used for the orange/glassy portion of the artifact was incredibly
> slow to render, so it took almost two days.
> 
> As a post-processing step I also wrote a simple brightness mask scene file that
> reads in an existing image and masks off (as black) areas that are below a
> specified brightness threshold. A simple 5x5 Gaussian convolution matrix is then
> iterated across the resulting masked image to blur the remaining pixels for a
> simple glow effect (not sure if this is similar to what Sam Benge does for his

> multi-pass rendering methods that I posted here a decade ago, the glow results
> are then composited with the original image (e.g., the halo around the

> 

like the the alien moon... nice!

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"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> Here is the result of assembling my sci-fi assets into a scene, as astronauts
> investigate an ancient alien artifact at sunrise on a distant world. The
> material I used for the orange/glassy portion of the artifact was incredibly
> slow to render, so it took almost two days.
>
> As a post-processing step I also wrote a simple brightness mask scene file that
> reads in an existing image and masks off (as black) areas that are below a
> specified brightness threshold. A simple 5x5 Gaussian convolution matrix is then
> iterated across the resulting masked image to blur the remaining pixels for a
> simple glow effect (not sure if this is similar to what Sam Benge does for his

> multi-pass rendering methods that I posted here a decade ago, the glow results
> are then composited with the original image (e.g., the halo around the




The figures are excellent - i love them...

I dont like the structure and the material - you made materials much more
elaborate than this...

Norbert

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"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:
> Here is the result of assembling my sci-fi assets into a scene, as astronauts
> investigate an ancient alien artifact at sunrise on a distant world. The
> material I used for the orange/glassy portion of the artifact was incredibly
> slow to render, so it took almost two days.
>
> As a post-processing step I also wrote a simple brightness mask scene file that
> reads in an existing image and masks off (as black) areas that are below a
> specified brightness threshold. A simple 5x5 Gaussian convolution matrix is then
> iterated across the resulting masked image to blur the remaining pixels for a
> simple glow effect (not sure if this is similar to what Sam Benge does for his

> multi-pass rendering methods that I posted here a decade ago, the glow results
> are then composited with the original image (e.g., the halo around the


This is efficient and reads like it was fast enough to lay out ! Good enough to
make us want more images like that please ! Maybe it would be worth getting
another discussion specifically about the slow orange material so that we get
the best experts views around here on how to tweak it faster or in the worse
case on what makes it so slow, maybe as a point to improve in later pov versions
?

My favourite part is the heightfield satellite.

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"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote:

That's a wonderful scene, very mysterious and evocative. And thanks for sharing
the details of your techniques, plus the image of the various assets you used.
>
> As a post-processing step I also wrote a simple brightness mask scene file that
> reads in an existing image and masks off (as black) areas that are below a
> specified brightness threshold.

That idea gave me some thoughts about my recent post regarding AA problems with
very bright objects, where AA fails for those bright pixels (Thanks!) So I put
together something similar(?) to your idea: Rendering a scene the normal way,
then bringing the image back into POV-ray and doing an
image-to-function-to-pigments conversion on it (all 3 color channels). Then
re-combining (using 'average') those 3 pigment functions-- with simple but
proper r-g-b color_maps-- to re-create the image as before. At this point, I
discovered that I could change the color_maps' index values to effectively
mask-off (as black) any pixels over a certain 0-1 brightness threshold... like
your idea. Great, so far!

> A simple 5x5 Gaussian convolution matrix is then
> iterated across the resulting masked image to blur the remaining pixels for a
> simple glow effect...

This is the 2nd part of my task. I looked up 'gaussian blur', and I see that it
involves matrix use in some way. I'm still a rank beginner when it comes to
manipulating matrices, but aside from that small problem (ha), I can't even get
a *basic* experiment with a matrix to work in v3.8xx for Windows:

#declare MY_MATRIX =
transform{
              matrix
              <1,1,1,
              1,1,1,
              1,1,1,
              0,0,1>
              }

.... with or without a semi-colon at the end. "Fatal error in parser:
uncategorized error"

So I must be doing something basically wrong-- or else my syntax is incorrect,
although I don't see where.

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William F Pokorny <ano### [at] anonymousorg> wrote:
> Cool. :-)
>
> The hint of atmosphere in the star field - is that something added to
> the star field, added as fog or is it related to the added luminous bloom?

It's just running some pigments through a couple of compositing macros and
building an averaged texture to "project" onto a background sky plane, something
like this:

#macro Pigment_Attenuate(p1, amt, rgb_clr)

   #local p2 = pigment { rgb rgb_clr }

   // return the new attenuated pigment
   #local pgmt_Attenuated = pigment {
      average
      pigment_map {
         [amt   p1]
         [1-amt p2]
      }
   }
   pgmt_Attenuated
#end

#macro Pigment_Overlay(pgmt_Orig, pgmt_Blend, blendAmt)

   #local pgmt_Blend = pigment {
      Pigment_Attenuate(pgmt_Blend, blendAmt, 0)
   }
   #local fp1 = function { pigment { pgmt_Orig } }
   #local fp2 = function { pigment { pgmt_Blend } }

   // overlay pigments
   #local RedChannel = pigment {
      function {
         (fp2(x,y,z).red*(1-fp1(x,y,z).red)/0.5)
        +(fp1(x,y,z).red-(1-fp1(x,y,z).red))
      }
      color_map { [0 rgb 0][1 rgb <1,0,0>] }
   }

   #local GreenChannel = pigment {
      function {
         (fp2(x,y,z).green*(1-fp1(x,y,z).green)/0.5)
        +(fp1(x,y,z).green-(1-fp1(x,y,z).green))
      }
      color_map { [0 rgb 0][1 rgb <0,1,0>] }
   }

   #local BlueChannel = pigment {
      function {
         (fp2(x,y,z).blue*(1-fp1(x,y,z).blue)/0.5)
        +(fp1(x,y,z).blue-(1-fp1(x,y,z).blue))
      }
      color_map { [0 rgb 0][1 rgb <0,0,1>] }
   }

   // return this new blended pigment
   #local pgmt_Blended = pigment {
      average
      pigment_map {
         [1 RedChannel]
         [1 GreenChannel]
         [1 BlueChannel]
      }
   }
   pgmt_Blended
#end

// stars
#declare P_Stars = pigment {
   image_map { png "starfield_and_moon" interpolate 2 map_type 0 once }
   translate -0.5
}

// atmosphere
#declare P_Clouds = pigment {
   gradient y
   pigment_map {
      [0
         bozo
         pigment_map {
            [0 rgb <44, 43, 58>/255]
            [1 rgb 0]
         }
         turbulence 1
         scale 0.2
      ]
      [0.75 rgb 0]
   }
   translate y*0.5
}

// Combined
plane {z, 200
   texture {
      average
      texture_map {
         [1
            pigment { Pigment_Overlay(P_Stars, P_Clouds, 0.15) }
            finish { emission 1 diffuse 0 }
         ]
         [1
            pigment { P_Stars }
            finish { emission 3 diffuse 0 }
         ]
      }
      scale x*image_width/image_height
      scale 160
      translate y*5
   }
}

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Thomas de Groot <tho### [at] degrootorg> wrote:

> Excellent! And Thanks for the detailed explanation; I shall note that
> carefully down for future study and use. The pose rig is particularly
> interesting for me. I have done some of this in Poser and there it is -
> not difficult - but demanding a close attention. How is this in Blender?
> more straightforward? Somehow, I guess it needs a close attention there too.

Thanks Thomas. The posing in Blender is pretty straightforward, it just takes
time to get all the bones in situated properly within the mesh. I spent about 3
hours building the rig and trying various poses.

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