POV-Ray rendering clipping faces

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paoligno90
Posts: 5
Joined: Sat Jun 22, 2019 2:12 pm

POV-Ray rendering clipping faces

Postby paoligno90 » Sat Jun 22, 2019 2:28 pm

Hello!

I recently started using FreeCAD to design some vacuum chambers. I create a part combining many .STEP files. I want to render the final object using POV-Ray and I get a strange behavior that I can't manage to explain. Attached are the model and the screenshots in the .zip archive. I render the entire assembly and some surfaces are completely invisible. You can see the differences in the files "Full*.png". If I make a big boolean cut with a cube, the faces appear correctly (files Big_Cut*.png), but if I cut a bit less entire pieces of the part disappear (files Small_Cut*.png). May this be related to the maximum number of polygons that FreeCAD is able to add to the POV-Ray project? Is there a way to overcome this?
Thank you very much
Attachments
Vacuum_chamber.zip
(812.62 KiB) Downloaded 10 times
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papyblaise
Posts: 449
Joined: Thu Jun 13, 2019 4:28 pm
Location: France

Re: POV-Ray rendering clipping faces

Postby papyblaise » Sat Jun 22, 2019 4:01 pm

Hello
Maybe , you have to do a total fuse of all parts , if you cut the main pipe, you obtain the alf pipe only wiyhout the flanges
schupin
Posts: 294
Joined: Sun Jan 21, 2018 1:43 pm

Re: POV-Ray rendering clipping faces

Postby schupin » Sat Jun 22, 2019 4:08 pm

Did you select all the part you want to render when you add it to the povray project ?

EDIT : if you've made it from the provided .step file, you shouldn't have problem. I'll try it by my side
paoligno90
Posts: 5
Joined: Sat Jun 22, 2019 2:12 pm

Re: POV-Ray rendering clipping faces

Postby paoligno90 » Sat Jun 22, 2019 4:53 pm

papyblaise wrote:
Sat Jun 22, 2019 4:01 pm
Hello
Maybe , you have to do a total fuse of all parts , if you cut the main pipe, you obtain the alf pipe only wiyhout the flanges
The part is already a single big piece.
schupin wrote:
Sat Jun 22, 2019 4:08 pm
Did you select all the part you want to render when you add it to the povray project ?

EDIT : if you've made it from the provided .step file, you shouldn't have problem. I'll try it by my side
It's only one single part. I tried with various cuts to see the differences in the .pov file. It seems that the number of meshes increases reducing the cut size and then it goes down losing some and therefore losing details and faces. I guess I will have to redo the part keeping different pieces and render them not as single piece, but still this is a very weird behavior
schupin
Posts: 294
Joined: Sun Jan 21, 2018 1:43 pm

Re: POV-Ray rendering clipping faces

Postby schupin » Sat Jun 22, 2019 5:25 pm

I took your .step and did this render with povray :
TstRayVaccum.png
TstRayVaccum.png (348.27 KiB) Viewed 243 times

I had zero issue
I'm using

Code: Select all

OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.17091 (Git)
Build type: Release
Branch: master
Hash: 4a0be9d3ba28ca14906574370de1f2f005af0d54
Python version: 3.6.8
Qt version: 5.12.1
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: French/France (fr_FR)
And 3.7 version of povray

(I modified the .pov file according to this pages : http://www.f-lohmueller.de/pov_tut/backgrnd/p_sky10.htm and https://www.freecadweb.org/wiki/Tutoria ... AD_POV_ray)
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quick61
Posts: 3793
Joined: Sat Aug 24, 2013 2:49 am
Location: u.S.A.

Re: POV-Ray rendering clipping faces

Postby quick61 » Sat Jun 22, 2019 6:22 pm

schupin wrote:
Sat Jun 22, 2019 5:25 pm
I took your .step and did this render with povray :
TstRayVaccum.png


I had zero issue
I'm using

Code: Select all

OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.17091 (Git)
Build type: Release
Branch: master
Hash: 4a0be9d3ba28ca14906574370de1f2f005af0d54
Python version: 3.6.8
Qt version: 5.12.1
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: French/France (fr_FR)
And 3.7 version of povray

(I modified the .pov file according to this pages : http://www.f-lohmueller.de/pov_tut/backgrnd/p_sky10.htm and https://www.freecadweb.org/wiki/Tutoria ... AD_POV_ray)
That's a very nice render! Would you mind sharing the script for that? you can copy and paste with the </> code tag or rename the .pov to .txt and attach. Looks like the HDRI environment mapping might make for a nice template.

Mark
This post made with 0.0% Micro$oft products - GOT LINUX?
schupin
Posts: 294
Joined: Sun Jan 21, 2018 1:43 pm

Re: POV-Ray rendering clipping faces

Postby schupin » Sat Jun 22, 2019 6:52 pm

quick61 wrote:
Sat Jun 22, 2019 6:22 pm
That's a very nice render! Would you mind sharing the script for that? you can copy and paste with the </> code tag or rename the .pov to .txt and attach. Looks like the HDRI environment mapping might make for a nice template.
Sure, here is the .pov file (I didn't put the mesh part that is a bit long (the .pov file is 35 Mo)) :

Code: Select all

// Persistence of Vision Ray Tracer Scene Description File
// for FreeCAD (http://www.freecadweb.org)

#version 3.7;

#include "colors.inc"
#include "metals.inc"  
#include "rad_def.inc"


// ----------------------------------------
#declare Rad_Quality = 3;

global_settings {
    assumed_gamma 1.0
    ambient_light color rgb <1.0,1.0,1.0>
    max_trace_level 20

#switch (Rad_Quality)
 #case (1)
    radiosity { // Settings 1 (fast)
        Rad_Settings(Radiosity_Fast, off, off)
    }
    #break
 #case (2)
    radiosity { // Settings 2 (medium quality)
        Rad_Settings(Radiosity_2Bounce, on, on)
    }
    #break
 #case (3)
    radiosity{ // Settings 3 (high quality)
        Rad_Settings(Radiosity_IndoorHQ, on, on)
        recursion_limit 2
    }
    #break
#end
}  

// ----------------------------------------


sky_sphere{ pigment{ image_map{ hdr "building_probe.hdr"
                                gamma 1.1
                                map_type 1 interpolate 2 }
                   }
            rotate < 0,10,0>  // adapt it to your direction
          } // end sky_sphere
                  

// ----------------------------------------

plane {
  y, -1
  texture { pigment {rgb <0.05,0.05,0.06>} finish {ambient 0.0 reflection 0.05 specular 0.0} }
}           


#declare T_metal = texture {T_Silver_1B}

// declares position and view direction

// Generated by FreeCAD (http://www.freecadweb.org/)
#declare cam_location =  <431.012,559.256,-486.816>;
#declare cam_look_at  = <-34.5,222.5,-8.83868>;
#declare cam_sky      = <-0.254258,0.889696,0.379203>;
#declare cam_angle    = 51; 
camera {
  location  cam_location
  look_at   cam_look_at
  sky       cam_sky
  angle     cam_angle 
  right x*800/600
}  

//default light
light_source {
  cam_location + cam_angle * 100
  color rgb <1.5, 1.5, 1.5>
} 

// Written by FreeCAD http://www.freecadweb.org/
// face number1 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#declare Pov_Part__Feature1 = mesh2{

MESH

}
// instance to render
object {Pov_Part__Feature
 texture {T_metal  }
}
The hdri image was taken here : http://www.pauldebevec.com/Probes/building_probe.hdr
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quick61
Posts: 3793
Joined: Sat Aug 24, 2013 2:49 am
Location: u.S.A.

Re: POV-Ray rendering clipping faces

Postby quick61 » Sat Jun 22, 2019 7:42 pm

schupin wrote:
Sat Jun 22, 2019 6:52 pm
quick61 wrote:
Sat Jun 22, 2019 6:22 pm
That's a very nice render! Would you mind sharing the script for that? you can copy and paste with the </> code tag or rename the .pov to .txt and attach. Looks like the HDRI environment mapping might make for a nice template.
Sure, here is the .pov file (I didn't put the mesh part that is a bit long (the .pov file is 35 Mo)) :
[snip code}
Thanks!
This post made with 0.0% Micro$oft products - GOT LINUX?
schupin
Posts: 294
Joined: Sun Jan 21, 2018 1:43 pm

Re: POV-Ray rendering clipping faces

Postby schupin » Sun Jun 23, 2019 10:24 am

paoligno90 wrote:
Sat Jun 22, 2019 4:53 pm
It's only one single part. I tried with various cuts to see the differences in the .pov file. It seems that the number of meshes increases reducing the cut size and then it goes down losing some and therefore losing details and faces. I guess I will have to redo the part keeping different pieces and render them not as single piece, but still this is a very weird behavior
I'm trying to make cuts in your part to do a slice render and I'm having some issues : I can't manage to do a boolean substraction with a cube to have a cut... Did you succeed doing such a cut in FreeCAD before render it ?
paoligno90
Posts: 5
Joined: Sat Jun 22, 2019 2:12 pm

Re: POV-Ray rendering clipping faces

Postby paoligno90 » Mon Jun 24, 2019 6:11 am

schupin wrote:
Sat Jun 22, 2019 6:52 pm
quick61 wrote:
Sat Jun 22, 2019 6:22 pm
That's a very nice render! Would you mind sharing the script for that? you can copy and paste with the </> code tag or rename the .pov to .txt and attach. Looks like the HDRI environment mapping might make for a nice template.
Sure, here is the .pov file (I didn't put the mesh part that is a bit long (the .pov file is 35 Mo)) :

Code: Select all

// Persistence of Vision Ray Tracer Scene Description File
// for FreeCAD (http://www.freecadweb.org)

#version 3.7;

#include "colors.inc"
#include "metals.inc"  
#include "rad_def.inc"


// ----------------------------------------
#declare Rad_Quality = 3;

global_settings {
    assumed_gamma 1.0
    ambient_light color rgb <1.0,1.0,1.0>
    max_trace_level 20

#switch (Rad_Quality)
 #case (1)
    radiosity { // Settings 1 (fast)
        Rad_Settings(Radiosity_Fast, off, off)
    }
    #break
 #case (2)
    radiosity { // Settings 2 (medium quality)
        Rad_Settings(Radiosity_2Bounce, on, on)
    }
    #break
 #case (3)
    radiosity{ // Settings 3 (high quality)
        Rad_Settings(Radiosity_IndoorHQ, on, on)
        recursion_limit 2
    }
    #break
#end
}  

// ----------------------------------------


sky_sphere{ pigment{ image_map{ hdr "building_probe.hdr"
                                gamma 1.1
                                map_type 1 interpolate 2 }
                   }
            rotate < 0,10,0>  // adapt it to your direction
          } // end sky_sphere
                  

// ----------------------------------------

plane {
  y, -1
  texture { pigment {rgb <0.05,0.05,0.06>} finish {ambient 0.0 reflection 0.05 specular 0.0} }
}           


#declare T_metal = texture {T_Silver_1B}

// declares position and view direction

// Generated by FreeCAD (http://www.freecadweb.org/)
#declare cam_location =  <431.012,559.256,-486.816>;
#declare cam_look_at  = <-34.5,222.5,-8.83868>;
#declare cam_sky      = <-0.254258,0.889696,0.379203>;
#declare cam_angle    = 51; 
camera {
  location  cam_location
  look_at   cam_look_at
  sky       cam_sky
  angle     cam_angle 
  right x*800/600
}  

//default light
light_source {
  cam_location + cam_angle * 100
  color rgb <1.5, 1.5, 1.5>
} 

// Written by FreeCAD http://www.freecadweb.org/
// face number1 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#declare Pov_Part__Feature1 = mesh2{

MESH

}
// instance to render
object {Pov_Part__Feature
 texture {T_metal  }
}
The hdri image was taken here : http://www.pauldebevec.com/Probes/building_probe.hdr
How did you manage to do that? When I export the .pov file it is only 600KB!! I don't have enough meshes!