Subject: Hello from a new user

Hi all,

I last used POV-ray about 25 years ago and I'm giving it another whirl. It sure
has changed since I was using DOS on an i386!

Back then I generated an image which I still have. But alas, the scene source
was lost a couple decades ago. It is a logo with the ocean below and patchy
clouds in the sky above. I'm trying to recreate that image now, with mixed
results. The CSG is challenging but fun. The sea and sky are a complete mystery.
I'd show you the original image but I don't know how.


beginner questions as I go. Looking forward to learning from the community.

Thanks,
---
netfoot

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"netfoot" <nomail@nomail> wrote:

> I last used POV-ray about 25 years ago and I'm giving it another whirl.

Welcome back!  :)

> I'd show you the original image but I don't know how.

Click the [Choose File] button right below the message text entry box.

Ask away - we are all here to help - because we're all still learning.

-BW




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On 2025-05-02 19:47 (-4), netfoot wrote:
> 
> I last used POV-ray about 25 years ago and I'm giving it another whirl. It sure
> has changed since I was using DOS on an i386!

Welcome back!

These are the main changes that you need to know:

 - Scene description files are expected to start with a #version
   statement.

 - Scene description files are expected to have an assumed_gamma in the
   global_settings{} block.  The default is 1.0, but this has
   implications for the appearance of your scenes.  (See below.)

 - If you're using version 3.8 beta, the default finish ambient is
   changed to 0.0, making shadows completely black.

 - Using radiosity disables all finish ambients.  If you wish to define
   a glowing object, use the new 'emission' keyword in the finish block.

If your POV-Ray version was up-to-date as of 25 years ago, the following
features may be familiar; but these were new at the time.

 - All declarations of floats and vectors require a terminating semi-
   colon.

 - Refraction is no longer a finish feature; it is now handled by the
   interior{} block.

 - Halos are obsolete, and are replaced with media.

There are more neat toys--most notably, true caustics using photon
mapping--but you can ease into these at your leisure.

More remarks are apropos about assumed_gamma--a lot more.  Be sure to
read the documentation on gamma handling very carefully.  Prior to
version 3.7, there was no default assumed_gamma, meaning that the scene
defaulted to your monitor's gamma, typically around 2.2; and colors to
this day are typically defined with this assumption[1].  To correct the
mismatch with assumed_gamma 1.0, such colors will need to be defined
with the 'srgb' keyword or, in the case of the named colors in
colors.inc, prefixed with the 'srgbft' keyword.

Introduction to Gamma:
https://blog.johnnovak.net/2016/09/21/what-every-coder-should-know-about-gamma/

Gamma handling documentation:
https://wiki.povray.org/content/Documentation:Tutorial_Section_3.3#Gamma_Handling

How to use the sRGB keywords: https://github.com/CousinRicky/POV-Gamma-sRGB

_________________
[1] Actually, they tend to assume sRGB nowadays rather than 2.2, but the
principle is the same.

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"netfoot" <nomail@nomail> wrote:
> Subject: Hello from a new user
>
> I last used POV-ray about 25 years ago and I'm giving it another whirl. It sure
> has changed since I was using DOS on an i386!
>

That's about the time I started with POV 3.1 dos. I think by then I had the 586.
 Glad to have you back! It seems you went one way and I went another. I dove
into POV to make graphics for PC games. Then used my knowledge of programing
games to make a front end for dos POV. Over the years the computers keep getting
upgraded and POV keep getting better and I learned a lot of more programing.
 I still have the code I wrote for 3.1 and all the files that came with it. So
when you talk about the scene your trying to reconstruct, I dug around and found
a scene wrote for 3.1 'WetPaint' that has most of what you described. I thought
it might have been one of the scenes files that came with 3.1 but it looks like
I made it. Here it is:

// scene: sign 'WET PAINT'on water
  #include "colors.inc"
    camera {
    location <0, 1, -10>
    look_at 0
    angle 35
  }
  light_source { <500,500,-1000> White }
  plane { y,0
     pigment { color SeaGreen }
    finish { reflection .35 specular 1 }
    normal { waves .5 }
    }

    text { ttf "timrom.ttf" "WET PAINT" 1, 0
      pigment { Gold }
      finish { metallic reflection .25 specular 1 }
      scale <1,2,1>
      translate -2.7*x
     }
  #include "skies.inc"
  sky_sphere { S_Cloud5 }

I hope this helps you on your come back to POV.
Also, You can visit my website: http://leroy.byethost15.com
You'll see some of what I've done over the last 25 years. There are some window
programs to help with prisms,lathes,height fields and so on. There are a few POV
object files and files to help with animations and more.

Have Fun!

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