Change backgrounds in post processing

LightWorks, VRay, Dribble, YafaRay and more..
User avatar
bitkar
Commander
Posts: 1454
Joined: 16 Mar 2010, 07:14
Type the number ten into the box: 0
Location: Czech Republic
Contact:

Re: Change backgrounds in post processing

Post by bitkar » 21 Jan 2016, 15:09

sooo many options... clinton is right... just render it as 32 bit PNG, its maybe easier, then load it into PS and add your background.
Michal aka bitkar
tS freak since tS2 (1998) and forever (tS7.61 modeler)

User avatar
the_ant
Petty Officer First Class
Posts: 73
Joined: 02 Jun 2009, 09:26
Type the number ten into the box: 0
Location: Perugia - Italy

Re: Change backgrounds in post processing

Post by the_ant » 22 Jan 2016, 13:24

Thank you all!!!!

i'll post the result of your help as soon as possible!!!!

:bananahi:

User avatar
the_ant
Petty Officer First Class
Posts: 73
Joined: 02 Jun 2009, 09:26
Type the number ten into the box: 0
Location: Perugia - Italy

Re: Change backgrounds in post processing

Post by the_ant » 06 Feb 2016, 10:54

i tried 32bit .png solution...but it seems to be wrong way...(see transparency of glasses)
Attachments
ClipAlfaGlassNotransp.jpg

clintonman
Captain
Posts: 3004
Joined: 21 May 2009, 21:08
Type the number ten into the box: 0
Location: California
Contact:

Re: Change backgrounds in post processing

Post by clintonman » 06 Feb 2016, 20:20

Check that you have raycast and raytracing enabled. You need both for transparency.
Clinton Reese

http://clintons3d.com

User avatar
bitkar
Commander
Posts: 1454
Joined: 16 Mar 2010, 07:14
Type the number ten into the box: 0
Location: Czech Republic
Contact:

Re: Change backgrounds in post processing

Post by bitkar » 08 Feb 2016, 09:44

and it works only for Lightworks, not Vray I think (not sure). If this wouldnt work maybe try to render to PSD and use the transparency channel.
Michal aka bitkar
tS freak since tS2 (1998) and forever (tS7.61 modeler)

User avatar
the_ant
Petty Officer First Class
Posts: 73
Joined: 02 Jun 2009, 09:26
Type the number ten into the box: 0
Location: Perugia - Italy

Re: Change backgrounds in post processing

Post by the_ant » 15 Mar 2016, 10:21

Hi all,

i must probably surrender to do this, (due to my learn limits too?)

i tried with your hints about... but always had wrong results.

Both raytracing and raycast "on" and "32bit png" fails to render a changeble background in post-pro

rear transparent objects like glass.

Same results with alpha set "on" in psd files.

Probably i need a tSp step by step tutorial but unobtainable on the web (actually).

Anyway ...thank you all to play attention about my questions and for your very quick answering.

You're all so special ...like this mighty forum!

Love so much tSp..its resources and its beautiful interface!

See you soon from Italy! :bananahi:

User avatar
Draise
Captain
Posts: 3096
Joined: 21 Sep 2009, 19:33
Type the number ten into the box: 0
Location: Bogota, Colombia
Contact:

Re: Change backgrounds in post processing

Post by Draise » 15 Mar 2016, 16:43

I gave it a shot myself. Yeah, you are right, in the PNG and PSD the alpha mask data does not account for the transparency of a shader.

And you cannot set the background color or image to anything with an alpha channel.

You can only put in a solid color.

Which means it's compllicated:
Use a color channel to drive a greyscale alpha mask in the post processed image. I do not know how to do this in photoshop or any layered system - but with nodes it's prettty easy.. but you'd need to be comfortable with postprocessing with a node based compositing system.

Sorry about the "not so simple" system.

Let me know if you need me to show you how to do it in Blender, Natron or Fusion 7 or something (all free node based compositing software).

User avatar
the_ant
Petty Officer First Class
Posts: 73
Joined: 02 Jun 2009, 09:26
Type the number ten into the box: 0
Location: Perugia - Italy

Re: Change backgrounds in post processing

Post by the_ant » 16 Mar 2016, 07:56

Thank you Draise

Have some hints in Blander could be fine (it will be a future challange in 3d software for me)..

..but i'm impressed/beloved (and don't want to leave) the capability of tSp to import "layered-3d-dxf (ascii r12)" files from Autocad-like programs (i'm an intellicad CMS 6.6 owner) i use for modelling (extrude-sweep-bool_opt) 2d polylines or regions.

So if you want ... i'll stay tuned in for yours "lectio magistralis" :worship:

P.S. I'm little weak in render Ambient Occlusion with Lightworks tSp 761 sp8 modelside...have you some hints about? :roll:

Thank you very very much.. :bananacheers:

cthulhu
Seaman
Posts: 7
Joined: 07 Sep 2015, 08:48
Type the number ten into the box: 10

Re: Change backgrounds in post processing

Post by cthulhu » 19 Mar 2016, 03:45

window.zip
(1.44 MiB) Downloaded 69 times
Attached is an example scene and output: Photoshop PSD (made in Paint Shop Pro) and TGA (32-bit uncompressed from trueSpace 7.5).

The shader for the glass is dual layer. Layer 1 has full transparency and layer 2 has glass with overdriven values for specular, mirror, etc. so that it shows up over the transparent layer.

Rendering to 32-bit uncompressed TGA, you can then load in a paint program, create a new layer, set the layer blending mode to Light, load a selection from the alpha channel, invert the selection, then paint/fill in the "background" with whatever.

Examples images:
window-tga-32bit.png
window-new-bg.png

User avatar
the_ant
Petty Officer First Class
Posts: 73
Joined: 02 Jun 2009, 09:26
Type the number ten into the box: 0
Location: Perugia - Italy

Re: Change backgrounds in post processing

Post by the_ant » 19 Mar 2016, 09:51

O.M.G. ..Amazing "cthulhu" :worship:

Thaaaaaaanks so much!!!

Immediately downloaded to explore your material...

so i'll apply your hints in my future scenes with glasses!!

:worship: :worship: :worship:

Post Reply