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29 Nov 2024 18:49:15 EST (-0500)
  For anyone new ... (Message 1 to 2 of 2)  
From: Mark Wright
Subject: For anyone new ...
Date: 16 Jan 1998 00:23:41
Message: <34befd21.0@news.povray.org>
Just hope this may help someone who's lost or new to the Pov Ray Scene like
I am. Play around with the code .. it renders quite fast. All you need to do
is Copy and Paste the source code below:


// Persistence of Vision Ray Tracer Scene Description File
// File: firstimage.pov
// Vers: 3.02 for Windows
// Desc: A simple picture with a breif tutorial
//       for creating your first image. Created from the
//       Help Documentation. Play around with the colors
//       numbers, camera, textures etc.
// Date: 01/16/1998
// Auth: Mark Wright



//STANDARD POV-RAY INCLUDES
//It is a good idea to have a look through them to see
//but a few of the many possible shapes and textures available.


#include "colors.inc" // Standard Color definitions
#include "textures.inc" // Standard Texture definitions



//THE BACKGROUND
//Pretty much explains itself.

    background { color Cyan }

//ADDING A CAMERA
//Briefly, location <0,2,-3> places the camera
//up 2 units and back 3 units from the center of
//the ray-tracing universe which is at <0,0,0>.
//By default +z is into the screen and -z is back out of the screen.
//
//Also look_at <0,1,2> rotates the camera to point at the
//coordinates <0,1,2>. A point 5 units in front of and 1 unit
//lower than the camera. The look_at point should be the center
//of attention of our image.

  camera {
    location <0, 2, -3>
    look_at  <0, 1,  2>
  }

//DESCRIBING AN OBJECT
//The first vector specifies the center of the sphere.
//In this example the x coordinate is zero so it is
//centered left and right. It is also at y=1 or 1 unit
//up from the origin. The z coordinate is 2 which is 5
//units in front of the camera, which is at z=-3.
//After the center vector is a comma followed by the radius
//which in this case is 2 units. Since the radius is half
//the width of a sphere, the sphere is 4 units wide.

   sphere {
    <0, 1, 2>, 2
    texture {
      pigment { color Yellow }
    }
  }

//DEFINING A LIGHT SOURCE
//The vector in the light_source statement specifies
//the location of the light as 2 units to our right
//4 units above the origin and 3 units back from the origin.
//The light source is invisible, it only casts light, so no texture is
needed.

  light_source { <2, 4, -3> color White}


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From: Stephen Horn
Subject: BUG REPORT for v3.02
Date: 24 Jan 1998 23:43:23
Message: <34cac2ab.294776996@news.povray.org>
There is a bug in POV-Ray version 3.02  (Win95 version).

When rendering scenes with radiosity the "brightness" setting will
default to 3.3 during a pixel-by-pixel trace.  During 2x2 traces, 4x4
traces, and etc, the brightness value specified in the scene file
gives the appropriate results, as soon as a 1x1 is reached, the value
will default back to 3.3

THIS IS NOT A MINOR PROBLEM.   Brightness is the most important
setting in POV-Ray's radiosity.  To get around it, I've had to use
light sources with colour-components greater than 1.0  This trick
ruins the scene where there is direct lighting and can never match the
results of higher brightness values no matter how much larger the
light's components are made.

This bug happens even if I repeat the "brightness" statement
continually in the scene file. Even after a restart of POV-Ray.  Even
after saving the scene. Even after rebooting. With or without
anti-alaising. With or without global ambience, with or without
assumed_gamma.  Even after closing all other programs and
re-rendering.

To see this problem in action, set the brightness to some ridiculous
value (around 55.0 or so).. The first pass of the scene, usually an
8x8, the scene will be washed-out in glowing white, then during the 
final pixel-by-pixel pass, the rendered lines should look noticably
darker.  This has happened at a myriad of brightness settings above
3.3


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