Is there a standard way to create a photo studio-like background (e.g.,
https://i.ebayimg.com/images/g/KxwAAOSwzvlW-6Kv/s-l1600.jpg)

It is the combination of two planes as an object shadow drops on them depending
on the distance.

I tried to make one by merging two perpendicular planes (to eliminate the
horizon line), but wasn't successful.

Post a reply to this message

"Kima" <nomail@nomail> wrote:

> I tried to make one by merging two perpendicular planes (to eliminate the
> horizon line), but wasn't successful.

You could use a bezier patch, a polynomial, blobbing together two planes

http://news.povray.org/povray.binaries.images/thread/%3Cweb.5cf31c5f43128c364eec112d0%40news.povray.org%3E/

doing an interpolation between two planes,

http://news.povray.org/povray.binaries.images/thread/%3Cweb.5d4b7ce3a683fa3a4eec112d0%40news.povray.org%3E/

or just use a curved function for an isosurface:



#version 3.8;
global_settings {assumed_gamma 1.0 }
#include "colors.inc"
#include "functions.inc"
#include "math.inc"



camera {
 //location <0, 0, -2.5>
 location <0, 5, -10>
 right x*image_width/image_height
 up y
 look_at <0, 2, 0>
 //look_at <0, 0, 0.01>
}
light_source {<10, 10, -10> rgb 1}
background {Gray10}

#declare Tan = texture {pigment {rgb <0.92, 0.60, 0.20>} finish {diffuse 0.7
specular 0.2 reflection 0.02}}


  isosurface {
    function {y-1/z}
    open
    threshold 0
    #declare Gradient = 1000;
    #declare Min_factor= 0.6;
    max_gradient Gradient
    //evaluate Gradient*Min_factor,  sqrt(Gradient/(Gradient*Min_factor)),  min
(0.7, 1.0)
    accuracy     0.01
    contained_by {box {<-3, 0, 0.0000001>, <3, 5, 5>}}
    //all_intersections
    polarity off
      interior_texture {Tan} texture {Tan}
      rotate y*180
     scale 1
     //translate -x*10
    }

Post a reply to this message

A very, very basic solution would be to make a union of very thin boxes 
(horizontal and vertical) joined by a quarter section of a horizontal 
cylindrical sheet with identical thickness (difference between two 
cylinders). You will be able to follow that up I am sure ;-)

-- 
Thomas

Post a reply to this message

On 8/21/19 12:36 PM, Kima wrote:
> Is there a standard way to create a photo studio-like background (e.g.,
> https://i.ebayimg.com/images/g/KxwAAOSwzvlW-6Kv/s-l1600.jpg)
> 
...
> 

Not sure about a standard way, but as have several others, Tek created a 
studio set up back in 2006 I've used. See:

http://news.povray.org/povray.binaries.scene-files/thread/%3C453d41ff%241%40news.povray.org%3E/

He posted a sample image too at the time to p.b.i.

Bill P.

Post a reply to this message

Op 22/08/2019 om 10:56 schreef William F Pokorny:
> On 8/21/19 12:36 PM, Kima wrote:
>> Is there a standard way to create a photo studio-like background (e.g.,
>> https://i.ebayimg.com/images/g/KxwAAOSwzvlW-6Kv/s-l1600.jpg)
>>
> ...
>>
> 
> Not sure about a standard way, but as have several others, Tek created a 
> studio set up back in 2006 I've used. See:
> 
>
http://news.povray.org/povray.binaries.scene-files/thread/%3C453d41ff%241%40news.povray.org%3E/

> 
> 
> He posted a sample image too at the time to p.b.i.
> 
> Bill P.

Now that you mention this, there is also Jaime Vives Piqueres:
http://www.ignorancia.org/index.php/technical/tools-objects/studio-lighting-kit/

-- 
Thomas

Post a reply to this message

Le 19-08-21 à 12:36, Kima a écrit :
> Is there a standard way to create a photo studio-like background (e.g.,
> https://i.ebayimg.com/images/g/KxwAAOSwzvlW-6Kv/s-l1600.jpg)
> 
> It is the combination of two planes as an object shadow drops on them depending
> on the distance.
> 
> I tried to make one by merging two perpendicular planes (to eliminate the
> horizon line), but wasn't successful.
> 
> 
Using merge does nothing to the line where the planes intersect. All it 
does is to suppress the surfaces that are inside the planes.

You can place a clipped cylinder to smooth it out.

union{
  plane{x, -1}
  plane{-z, -1}
  cylinder{1001*x, -1001*x, 1
    clipped_by box{<1000,0,0><-1000,-1,-1> inverse}
   }
}

Adjust the radius of the cylinder, the clipping box and location of the 
planes to suit your need.

Post a reply to this message