POV-Ray

Using the concat function is tedious. Why not just have an operator with which to concatenate strings?

“Hello " + “world!”

“Hello " . “world!”

When right-clicking on a tab in the editor window a list of options should appear, such as:

* Close
* Close all but this
* Save
* Save as
* Print

See Notepad++, EditPad Lite, and Firefox for examples.

It would be nice to configure an INI option to add render information like render time, date, and input file to output images.

There are various scripts around the Net meant for approximating things like isosurfaces and parametric objects using meshes. It would probably run bit faster and be easier to use if this were supported natively within Povray. The feature would require an additional object parameter in order to toggle this behavior on/off.

Currently, many POV scenes/include files behave differently depending on the basic units used within the scene. Scaling them differently can affect things like ior and media. A master system variable that users can set to configure the scene’s units would be beneficial for sharing and collaboration purposes, so that person A’s glass interior works correctly in person B’s wine glass scene. Just like the #version system variable, it should have a default value but should be possible to explicitly override.

Currently, arrays may contain only one object type. Would be nice to eliminate this restriction and allow arrays to contain objects of different types.

In POV SDL it can sometimes be ambiguous what exactly a macro returns. An explicit #RETURNS statement would make this unambiguous.

Request a system variable to test whether a scene file has been included by another scene file.

For instance:

#if (is_included)
  camera {...}
#end

Many programming languages support an indeterminate number of parameters in functions/macros.

JavaScript for instance supports an “arguments” object.

Lua for instance supports the “args” object.

I would like to see that added to POV as well.

Here’s an JavaScript example:

function ArgTest(a, b){
   var i, s = "The ArgTest function expected ";
   var numargs = arguments.length;     //Get number of arguments passed.
   var expargs = ArgTest.length;       //Get number of arguments expected.
   if (expargs < 2)
      s += expargs + " argument. ";
   else
      s += expargs + " arguments. ";
   if (numargs < 2)
      s += numargs + " was passed.";
   else
      s += numargs + " were passed.";
   s += "\n\n"
   for (i =0 ; i < numargs; i++){      //Get argument contents.
   s += "  Arg " + i + " = " + arguments[i] + "\n";
   }
   return(s);                          //Return list of arguments.
}

Request #BREAK statement inside #WHILE and #FOR loops.

Request an #ELSEIF statement in POV SDL.

Assuming there are no performance issues, it would be nice to tell Povray to select the pixels to render randomly, so that the image gets filled in gradually instead of from top to bottom and from left to right.

Also, maybe an option to tell it to render every Nth pixel.

20 library paths is a bit small given the sheer number of include files I’ve collected over the years. An increase in the number, and/or the ability to include wildcards in the search path, would be great.

There should be a table of contents on each page of the documentation, or at least on the very long pages. Scrolling through the entire page to figure out what topics are covered sucks.

The included scenes\advanced\benchmark.pov (v1.02)is different then the winpov menu render\run benchmark (v2.01).

The winpov menu render\run benchmark is missing some objects, turned off in early betas?

When using “filter all VALUE” with an image_map using a 4-bit (16-color) paletted bmp image, debug builds of POV-Ray fail with an assertion.

According to code analysis, other paletted image formats with <256 palette entries are also likely to be affected; similar assertion fails can be expected when using the “filter INDEX, VALUE” feature on such files with an index exceeding the palette size. “transmit” shows the same flaws.

Mosaic preview display didn’t work as expected, given these command line options: +sp64 +ep16. The preview was solid colored instead of the coarse preview that you’d expect.

I’ve tested a fix to unix/disp_sdl.cpp from clipka and it appears to work.

Reflections in multi-layered textures are broken in 3.7 betas, as can be demonstrated with the following scene showing two reflective hemispheres on a checkered plane:

camera {
  location  <1.0, 0.5, -4.0>
  direction 1.5*z
  right     x*image_width/image_height
  look_at   <0.0, 0.0,  0.0>
}

sky_sphere {
  pigment {
    gradient y
    color_map {
      [0.0 rgb <0.6,0.7,1.0>]
      [0.7 rgb <0.0,0.1,0.8>]
    }
  }
}

light_source {
  <0, 0, 0>            // light's position (translated below)
  color rgb <1, 1, 1>  // light's color
  translate <-30, 30, -30>
}

default {
 finish { diffuse 0 ambient 0 specular 0 }
}

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

plane {               // checkered floor
  y, -1
  texture
  {
    pigment { checker color rgb 1 color blue 1 }
    finish{ diffuse 0.8 ambient 0.1 }
  }
}

// left hemisphere
intersection {
  sphere { 0, 1 }
  plane { x, -0.002 }
  texture {
    pigment { color rgb 1 }
    finish{ reflection { 0.5 } }
  }
  texture {
    pigment { color rgbt 1 }
    finish{ reflection { 0.4 } }
  }
  texture {
    pigment { color rgbt 1 }
    finish{ reflection { 0.1 } }
  }
}

// right hemisphere
intersection {
  sphere { 0, 1 }
  plane { -x, -0.002 }
  texture {
    pigment { color rgb 1 }
    finish{ reflection { 1.0 } }
  }
}

Note that the reflection parameters of the left, multi-layered hemisphere sum up to 1.0, i.e. the same value as used in the single layer in the right hemisphere.

The first attached file (test_3.6.2.png), rendered with POV-Ray 3.6.2, shows the expected output: Both hemispheres appear to have the same reflectivity.

The second attached file (test_3.7.0.beta37a.png), rendered with POV-Ray 3.7.0.beta.37a, shows a much brighter left (multi-layered) sphere.

As it turns out, in order to get the expected result with POV-Ray 3.7.0.beta.37a, the reflectivity of each layer must be divided by 3, 2 and 1, respectively (which obviously does not sum up to 1.0):

  ...
  texture {
    pigment { color rgb 1 }
    finish{ reflection { 0.5 / 3 } }
  }
  texture {
    pigment { color rgbt 1 }
    finish{ reflection { 0.4 / 2 } }
  }
  texture {
    pigment { color rgbt 1 }
    finish{ reflection { 0.1 / 1 } }
  }
  ...

OpenEXR output currently writes an alpha channel when Output_Alpha=off (-UA), and does not write an alpha channel when Output_Alpha=on (+UA), i.e. doing it just the wrong way round.

Automatic removal of user-specified bounding boxes cannot be disabled in current POV-Ray 3.7 betas; the Remove_Bounds ini file setting and the +/-UR command line option are silently ignored.

The following line in the lathe1a.pov, lathe1b.pov, and lathe1c.pov appears to have an error in it.

  <3.6.9>, <4, 1.1>, <3.4, 2>, <3, 1>, <2, 1>,

Although it works in version 3.6, only in 3.7 does a render time error ocurr.

Scene source should be adjusted to the following

  <3.6, 0.9>, <4, 1.1>, <3.4, 2>, <3, 1>, <2, 1>,

The function of the “Debug_File=” .ini option has changed from 3.6 to 3.7.37a.
In 3.6, when rendering multiple frames, a debug file would be created that then appended the debug lines for each frame into the file. It was therefore able to have debug data that identified what parameters were used in which frame in case a frame did not have the desired effect.

In 3.7.37a, the debug file does not perform this function. Instead it creates a new debug file (overwriting the prior) with each new frame. Therefore the debug data is only useful for the final frame (or wherever the render was halted). This is useful for a single frame render or for identifying a fault within a series of frames (because only the last one will remain) but it is not useful for many frames that render successfully.

This problem does not cause any rendering errors or other defects. The debug file specified will only contain the debug data for the last frame rendered.

Per discussion in the forum it was unknown if this was a bug or “feature”. At this time it is causing me a problem so I am submitting the bug. No related bugs were found searching for “output” or “debug” in any status.

Operating System in use is Windows XP. I cannot test 3.7.37a in additional OSes, but it does not seem like it would be OS-specific.

I can no longer run a Myfile.ini over a network, on a different computer.

Possiblely related to:

    http://bugs.povray.org/task/97   FS#97  (Forward-slash pathnames not fully supported in Windows version)

-
Cannot open INI file
‘\\STEPHEN-POVRAY\Bishop3d\Objects\Industrial_enclosure\Telco_enclosure_extra.ini’.
Failed to start render: Failed to parse INI file

POV-Ray 3.7 does not show output options, such as:

Output Options
  Image resolution 640 by 480 (rows 1 to 480, columns 1 to 640).
  Output file: D:\foo\test.png, 24 bpp PNG
  Graphic display......On  (gamma: 2.2)
  Mosaic preview.......Off
  CPU usage histogram..Off
  Continued trace......Off

(the above is what 3.6 used to show)

Setting File_Gamma=1.0 produces unexpectedly bright output files for most output file formats, as if File_Gamma was set to 2.2 instead.

The underlying problem is a bug that, when File_Gamma is set to exactly 1.0, causes the encoding gamma function to be undefined, which was not meant to happen in current versions, and instead was reserved for future versions to signal that a file-format-specific default encoding gamma should be used. The image file output handlers already support this, most of them choosing the sRGB transfer function, giving roughly the same output as setting File_Gamma=2.2.

As a preliminary workaround, users may want to set File_Gamma=1.02 (any value smaller than 0.99 or greater than 1.01 should do).

POV-Ray 3.7-generated JPEG image output files do not conform to the JFIF standard. Most importantly, the files written do not use the standard YCbCr color model (they seem to use plain RGB instead), nor do they have a proper JFIF tag.

As a consequence, some software may be unable to read the generated JPEG files properly. In addition, it seems that POV-Ray mixes up the Red and Blue channels.

The #switch directive isn’t parsing correctly. In the following construct NO warning or error is generated:

#switch (RF)

case (0)
	rotate z*355
#break
case (144)
	rotate z*7.5
#break
case (216)
	rotate z*5
#break

#end

RF is a variable passed to the macro in which this construct resides. The first ‘case’ action IS executed, but none of the others are on successive calls to the macro. If I properly add ‘#’ to the second case the 1st and 2nd condition are executed but not the last. If ‘#’ is REMOVED from any of the break directives an error is generated and parsing halts.

woodmaps.inc depends on colors.inc, more specifically the definition of the color “Clear” perhaps a #ifndef colors.inc belongs in woodmaps.inc or probably more correctly changing the call of “Clear” to rgbf 1

When using cutaway_textures the differenced part traces black. Simple scene file attached.

The current Windows version of POV-Ray does not fully support forward slashes in pathnames; specifically, POV-Ray fails to recognize drive letters when followed by a forward slash, e.g. “C:/foo/bar.pov” or “C:/foo\bar.pov”, rejecting such names for e.g. Input_File_Name.

The code to attenuate transmitted photons according to surface texture was apparently duplicated during refactoring of the source code for version 3.7. Behavior has changed from 3.6 to 3.7 (beta.36) accordingly, as can be demonstrated with the following scene:

global_settings {
  assumed_gamma 1.0
  max_trace_level 10
  photons { spacing 0.02 }
}

camera {
  right x*image_width/image_height
  location  <0,2.6,-10>
  look_at   <0,0.75,0>
}

light_source {
  <500,300,150>
  color rgb 1.3
  photons {
    refraction on
    reflection on
  }
}

sky_sphere {
  pigment {
    gradient y
    color_map {
      [0.0 rgb <0.6,0.7,1.0>]
      [0.7 rgb <0.0,0.1,0.8>]
    }
  }
}

plane {
  y, 0
  texture { pigment { color rgb <1.0, 0.8, 0.6> } }
}

#declare M_Glass=
material {
  texture {
    pigment {rgbt 1}
    finish {
      ambient 0.0
      diffuse 0.05
      specular 0.6
      roughness 0.005
      reflection { 0.1, 1.0 fresnel on }
      conserve_energy
    }
  }
  interior {
    ior 1.5
    fade_power 1001
    fade_distance 0.9
    fade_color <0.5,0.8,0.6>
  }
}

#declare M_PseudoGlass2=
material {
  texture {
    pigment {rgbf <0.8,0.2,0.2,0.8>}
    finish {
      ambient 0.0
      diffuse 0.05
      specular 0.6
      roughness 0.005
      reflection { 0.1, 1.0 fresnel on }
      conserve_energy
    }
  }
  interior {
    ior 1.0
  }
}

sphere {
  <1.1,1,-1.3>, 1
  material { M_Glass }
  photons {
    target 1.0
    refraction on
    reflection on
  }
}

box {
  <2.4,0,-2.3>, <2.6,4,0.3>
  material { M_PseudoGlass2 }
  photons { target 1.0 refraction on reflection on }
}

I’ve tried to model this setup:
http://kschwebke.webng.com/povray/ior-interfaces/drawing.png with the following SDL:
http://kschwebke.webng.com/povray/ior-interfaces/rs2.pov.txt

A small overlap between the two transparent solids is needed, because a gap
would lead to total reflection. The camera in the test scene looks in the
direction of the ray in the setup drawing. The setup is surrounded with angular
markers, so one can easily read the final resulting looking angle.

POV-Ray 3.6.1 renders the expected result (~53° in the center of the screen):
http://kschwebke.webng.com/povray/ior-interfaces/rs2-35.jpeg

POV-Ray 3.7.0b35a (compiled Unix source) renders a different
(and in my opinion wrong) angle (~67°), however – for the very same scene file:
http://kschwebke.webng.com/povray/ior-interfaces/rs2-37b35a.jpeg

I’ve started a discussion about this issue in povray.beta-test: http://news.povray.org/povray.beta-test/thread/%3Cweb.4bba4677730ab9f3e8c084b40%40news.povray.org%3E/

All linked documents are also attached.

The following scene shows how photons are “boosted” by pass_through objects; removing one of the boxes will reduce the effect; the effect can be seen with 3.6 as well as current betas:

global_settings {
  max_trace_level 10 // makes a difference!
  photons { spacing 0.02 }
}

camera {
  right x*image_width/image_height
  location  <0,2.6,-10>
  look_at   <0,0.75,0>
}

light_source {
  <500,500,150>
  color rgb 1.3
  photons {
    refraction on
    reflection on
  }
}

sky_sphere {
  pigment {
    gradient y
    color_map {
      [0.0 rgb <0.6,0.7,1.0>]
      [0.7 rgb <0.0,0.1,0.8>]
    }
  }
}

plane {
  y, 0
  texture { pigment { color rgb <1.0, 0.8, 0.6> } }
}

#declare M_Glass=
material {
  texture {
    pigment {rgbt 1}
    finish {
      ambient 0.0
      diffuse 0.05
      specular 0.6
      roughness 0.005
      reflection { 0.1, 1.0 fresnel on }
      conserve_energy
    }
  }
  interior {
    ior 1.5
    fade_power 1001
    fade_distance 0.9
    fade_color <0.5,0.8,0.6>
  }
}


sphere {
  <1.1,1,-1.3>, 1
  material { M_Glass }
  photons {
    target 1.0
    refraction on
    reflection on
  }
}

cylinder {
  <-1.2,0.01,0.8>, <-1.2,2.5,0.8>, 1
  material { M_Glass }
  photons {  // photon block for an object
    target 1.0
    refraction on
    reflection on
  }
}

box {
  <2.4,0,-2.3>, <2.6,4,-0.3>
  material { M_Glass }
  photons { pass_through }
}

box {
  <2.9,0,-2.3>, <3.1,4,-0.3>
  material { M_Glass }
  photons { pass_through }
}

This item may need to be merged with item FS#81. This is another sphere sweep bug, though they are of different spline types.

The code is

#include "colors.inc"

camera {
  location  <0, 0.0, -4.0>
  direction 1.5*z
  right     x*image_width/image_height
  look_at   <0.0, 0.0,  0.0>
}

light_source {
  <0, 0, 0>            // light's position (translated below)
  color rgb <1, 1, 1>  // light's color
  translate <-30, 30, -30>
}


#declare i_start = 0;
#declare i_stop = 3;
#declare i_step = 0.05;
#declare i_inc = i_start;
sphere_sweep {
  linear_spline                 // linear curve

  (i_stop - i_start)/i_step + 1,    // number of specified sphere positions
#while(i_inc<=i_stop)
  
  #declare y_coor = 0.23*sin(7.1*i_inc);
  <i_inc, y_coor, 0>, 0.05
        #declare i_inc = i_inc + i_step;
 
        
#end

pigment{color Orange}

}

The following code is erroneously accepted by POV-Ray (tested with 3.7.0.beta.36):

pigment{
  slope { x }
  checker
}

The result is a checker pattern.

Apparently there is an EXIT statement missing in the slope-pattern parsing code in parstxtr.cpp.

When choosing PPM output with a bit depth other than 8 bits per color channel (e.g. +FP16), POV-Ray messes up the colors (see thread news://news.povray.org:119/4babb48f$1@news.povray.org)

File output code for virtually all file formats performs gamma correction on unclipped color values, which leads to issues when color values happen to be negative for some reason and gamma does not happen to be an integer value such as 1.0 or 2.0. As a consequence, subsequent steps (clipping and converting to integer) apparently produce compiler-dependent results. Compiled with Microsift or Intel compilers, POV-Ray seems to write zero brightness in such cases, while compiled with g++ 4.4 (and possibly other compilers) it seems to write full brightness instead.

(See thread news://news.povray.org:119/4ba819f6@news.povray.org for examples.)

The proper solution should be to apply gamma correction after clipping.