POV-Ray

Suggestion:

In file screen.inc, have macro Screen_Object() set no_radiosity on the object.

I’ve got an ini file that looks like this:

Post_Frame_Return=U
Post_Frame_Command=notepad.exe

And when I render a scene using that ini file, it renders correctly but then
gives me this error:

Render halted because the post-frame shell-out (’notepad.exe’) requested POV-Ray
to generate a user abort.
Render failed

.....and it doesn’t open notepad.

I’ve unchecked the “Disable Starting Other Programs” and I’ve tried various
variations on what exe to run and whether to do it Pre/Post Frame/Scene, and
nothing has worked.

How to reproduce:

# An empty directory, an empty source file.
$ mkdir test && cd test && touch test.pov
# Generate the first 24 frames.
$ povray -D +KFF24 +Itest.pov +Otest.png
# Try to generate the 25th frame.
# `25' after `+KFF' can be changed to any integer greater than 24.
$ povray -D +C +KFF25 +Itest.pov +Otest.png

What happens:

==== [Parsing...] ==========================================================
Possible Parse Error: Cannot find file 'test.pov', even after trying to append
 file type extension.
Parse Error: Cannot open input file.
Fatal error in parser: Cannot parse input.
Render failed

OS: Gentoo AMD64 unstable
POV-Ray version: 3.7.0 rc5

Compiling the sources with clang instead of g++ (on ubuntu 12.10 with boost 1.50)

./configure COMPILED_BY=”your name here <also@email>” LIBS=-lboost_system –disable-io-restrictions CC=clang CXX=clang

there is a few warnings that catch the eyes (and other as well that I dismiss so far, such as cases not covered in switch and empty body in if, or extraneous parentheses in tests):

support/randomsequences.cpp:553:15: warning: field is uninitialized when used here [-Wuninitialized]
                        startIndex(startIndex)
                                   ^
support/randomsequences.cpp:553:15: warning: field is uninitialized when used here [-Wuninitialized]
support/randomsequences.cpp:974:40: note: in instantiation of member function 'pov::PrecomputedNumberGenerator<int>::PrecomputedNumberGenerator' requested here
        SeedableIntGeneratorPtr generator(new PrecomputedIntGenerator(factory, count));
                                              ^
support/randomsequences.cpp:553:15: warning: field is uninitialized when used here [-Wuninitialized]
                        startIndex(startIndex)
                                   ^
support/randomsequences.cpp:984:43: note: in instantiation of member function 'pov::PrecomputedNumberGenerator<double>::PrecomputedNumberGenerator' requested here
        SeedableDoubleGeneratorPtr generator(new PrecomputedDoubleGenerator(factory, count));
                                                 ^
support/randomsequences.cpp:553:15: warning: field is uninitialized when used here [-Wuninitialized]
                        startIndex(startIndex)
                                   ^
support/randomsequences.cpp:1011:43: note: in instantiation of member function 'pov::PrecomputedNumberGenerator<pov::Vector3d>::PrecomputedNumberGenerator' requested here
                return SequentialVectorGeneratorPtr(new PrecomputedVectorGenerator(factory, count));
                                                        ^
support/randomsequences.cpp:553:15: warning: field is uninitialized when used here [-Wuninitialized]
                        startIndex(startIndex)
                                   ^
support/randomsequences.cpp:1056:45: note: in instantiation of member function 'pov::PrecomputedNumberGenerator<pov::Vector2d>::PrecomputedNumberGenerator' requested here
                return SequentialVector2dGeneratorPtr(new PrecomputedVector2dGenerator(factory, count));

Self referencing member in creator does not seems to be great for a reproducible pseudorandom generator (some compiler/architecture might force to 0, other might not... seems bad karma).

                           
             povmscpp.cpp:1875:4: warning: delete called on 'POVMS_MessageReceiver::HandlerOO' that is abstract but has non-virtual destructor [-Wdelete-non-virtual-dtor]
                        delete nodeptr->handleroo;
                        ^
povmscpp.cpp:1877:4: warning: delete called on 'POVMS_MessageReceiver::Handler' that is abstract but has non-virtual destructor [-Wdelete-non-virtual-dtor]
                        delete nodeptr->handler;
                        ^

Maybe just a missing keyword (virtual) in the header file ? Or is it harder ?

shelloutprocessing.cpp:260:28: warning: expression result unused [-Wunused-value]
        for (s = str.c_str(); *s; *s++)
                                  ^~~~

Why “*s++” ? why not just “s++” ?

renderfrontend.cpp:1165:57: warning: trigraph ignored [-Wtrigraphs]
                                        default:                                    t = "(???)";                            break;
 

I guess it’s not an intended trigraph. Might nevertheless perturb some compiler/result.

There are times when scaling an entire scene up or down is difficult or just not feasible.

One suggestion is a global_settings option.

Also, I’ve noticed that in some situations, such as interactions between certain transparent objects, the epsilon seems to kick in quite early. Perhaps there could be situational or contextual epsilons, such as the “tolerance” of sphere_sweep or the “accuracy” of isosurface.

After a long parse period and a relatively quick rendering, POVray gets stuck at 99% when rendering the attached file.

Rendered at 6144x3072px with antialiasing set to 0.3.

Can anyone confirm?

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.

...for instance nVidia’s CUDA architecture, discussed here and other places.

General consensus is that it’s not worth the effort if only a partial set of POV-Ray’s features are possible.

‘povray -H10 -W20 myscene.pov’ will generate a file with a picture 10 pixels high and 20 pixels wide, BUT in the message pane it displays

Image resolution.....20 by 10 (rows 1 to 20, columns 1 to 10)

instead of

Image resolution.....20 by 10 (rows 1 to 10, columns 1 to 20)

or

Image resolution.....20 by 10 (columns 1 to 20, rows 1 to 10) 

The following (bogus) SDL code causes POV-Ray 3.7 beta to crash hard with an access violation:

#include "fubar.inc"
Bar(42)
#macro FooBar() #end

//fubar.inc
#macro Foo(Fnord) #end
#macro Bar(Ignord) Foo(23 #end

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.

#macro A()
  #local foo = function { x }
  foo
#end

#local bar = A();

This causes either a segfault, corruption detected by malloc, or “Parse Error: Unknown user defined function”.

After some debugging I think this is what happens.

In source/backend/parser/parse.cpp, Parser::Parse_RValue is called to define the value of bar. Get_Token is called, which invokes A() and which ultimately returns foo as a FUNCT_ID_TOKEN. This token is handled by CASE_VECTOR in Parse_RValue. The relevant clause calls Parse_Unknown_Vector to parse additional tokens (e.g. “foo ( 1 )”). There aren’t any other tokens, but in the process of determining that, #end is reached and Return_From_Macro destroys the symbol table of A, including foo.

So by the time the CASE_VECTOR clause decides that foo is a function identifier that should be copied, the function is destroyed (both the function itself and its number in the symbol table). So here:

    Temp_Data  = (void *) Copy_Identifier((void *)*Token.DataPtr,*Token.NumberPtr);

if *Token.DataPtr (in this case, a function index) was already overwritten, we get “Unknown user defined function”; if it still has the valid function number, it increments the reference count of the function (which has already been freed) back from 0, and we get a double-free later.

A similar problem occurs when foo is a spline.

A tentative patch for the function case is attached.

Consider the following script:

  #fopen F "foo.txt" read
  #read (F, Foo)
  #debug concat ("'", Foo, "'\n")
  #fclose F

Now assume that foo.txt erroneously contains unquoted text (which will result in a parse error):

  Blah

When the error is reported, POV-Ray for Windows will helpfully open foo.txt, but any attempt to save a corrected version of foo.txt will fail until you exit the POV-Ray GUI, presumably because foo.txt is not properly closed by the parser.

Input image files may have been created with gamma pre-correction for some specific target gamma, which may vary from image to image. Some file formats like PNG or HDR support embedding gamma pre-correction information in the image file, but this information may be missing or faulty, and some formats don’t support it at all. Additionally, it may be desirable to tamper with an input image’s gamma for artistic reasons.

Therefore, I suggest adding a means to explicitly specify input images’ originally intended target gamma on a per-image basis, like:

image_map { jpeg "MyImage.jpg" assumed_gamma 1.8 }

3.6x only bug with easy/known fix. Error message: “Identifier expected, incomplete function call or spline call found instead.” caused by token counter variable using the wrong special value. The symptom occurs when using a lot of splines. See this thread for details.

(I am using a self-compiled special build because I use a lot of splines in 3.6 but would rather use an official 3.6)

Reported by cshake + pov @ gmail . com in p.beta-test, 14th december 2009

I wrote a simple script to convert fractint color maps to povray color_maps so I could use ApoMap to make nice fractal colors for pov, but I ran into
“Parse Error: Blend_Map too long.” The map has entries from 0/255 up to 255/255 (inclusive). I looked up the documentation which says that color_maps can have from 2 to 256 entries, and this is exactly 256 entries.
I’m posting this in beta-test because I assume that the documentation is correct for v3.6, and that a previous version can handle 256 entries.

The following SDL code

sphere {0, 1 pigment {image_map {png "missing.png"}}

yields “render failed” in 3.7b25 and the position of the error
is not highlighted in source code, giving no clue what went wrong.
In 3.6 this yields “Parse Error: Cannot open PNG file”.

no warning is issued when an object/primitive has no pigment type given

Given the following two statements, a missing closing brace in the function declaration fn should throw a parse exception; instead it causes a memory access violation when trying to use fn in the second delcaration:

#local fn = function { 
  pigment { image_map { png "MultiPassBlobs3.png" gamma 1 map_type 0 once }} 
#local clr = fn(0,0,0);

Hello,

this bug report relates to this thread: http://news.povray.org/povray.beta-test/thread/%3Cweb.4e0064d9a3970d212b256d410%40news.povray.org%3E/

In /unix/unixoptions.cpp around line 817:

while ( !Stream.eof() )
{
	// get and preprocess line
	std::getline(Stream, line);
	line = pre_process_conf_line(line);
	++line_number;
	// skip empty line
	if(line.length() == 0)
		continue;
        [...]
}

`Stream.eof()` could never be true as well as `line.length()` always can be zero, leading to an endless loop. In my case, the problem occurred due to my ~/.povray/3.7/povray.conf being a directory instead of a file.

To fix the problem, one has to consolidate this loop by not only checking for eofbit, but also for failbit and badbit of `Stream`. The getline() method on a directory does not set the eofbit, but it sets fail and bad (test: http://codepad.org/RiZGo3ia). According to http://www.cplusplus.com/reference/iostream/ios/operatornot/ fail and bad can be checked for by `!Stream`. A simple `if (!Stream) break;` within the loop fixes the problem (patch file attached).

Are there more missing checks on iostreams like this in the code? :) They should definitely be fixed.

Furthermore, one could think about using the boost filesystem library to be able to distinguish files and directories to provide good error messages.

Hope that helps,

Jan-Philip Gehrcke

I would like to suggest an additional feature regarding splines. POV-Ray’s spline objects (spline {}) are very useful to create animation paths as a function of time from reference points; however, in many cases you do not only need a position to place an object correctly, but also its velocity etc., e.g. if you are animating a car moving along a spline you do not only need to know where the car is at a given clock value but also in which direction it is going. If you want to rotate the wheels correctly you even need to know how this direction is currently changing.

In a nutshell, if you are using splines to create an animation path, you might not only need the spline value itself, but also the value of its first and second derivative. So I suggest adding an SDL capability to access these values like it is possible to access the spline value for a given parameter.

I do not think it would be too difficult to add a feature like this as far as the backend is concerned, since for computing a (cubic) spline you need the first and second derivatives anyway. (They are probably not being stored separately, but a polynomial is not that hard to differentiate.)

Indeed I do not know how an SDL language construct for it should look like (i.e. whether to use ' and ‘’ like in mathematics or a second spline function parameter).

Adjusting the brightness of an image-mapped sky sphere, although not an uncommon task especially when using HDR light probes, currently is cumbersome at best, as it is not possible to specify a “finish { ambient ... }” statement.

To simplify tuning a sky sphere’s brightness, I suggest introducing a “brightness FLOAT” modifier (defaulting to 1.0) to either the sky_sphere block or (as a more versatile solution) the image_map statement.

The parser is missing extra period characters when it parses a float as a vector component.

#local sample = <0.0.0.1,0,0>;

Doesn’t generate an error, but should.

The parser does not accept mesh objects (or CSG objects including a mesh object) as a parameter to the inside() built-in function, reporting error “Solid object identifier expected”, even if the mesh is “solidified” by specifying an inside_vector.

(see news://news.povray.org:119/4a983716@news.povray.org)

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.

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

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.

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.

Request an #ELSEIF statement in POV SDL.

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

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

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

Macros are finicky about how you type your code. What works outside macros sometimes fails inside them. For more information see the threads:

“Problems with macro (3.6)”, in p.a-u, 06-09-10
“Bad operands”, in p.g, 05-20-10

Still not sure *what* exactly the problem was, but one of my workarounds ended up working.

Currently, cameras placed inside object or union statements will halt the render with an error. Take for instance the following case:

#local temp_camera_1 = camera
{
  orthographic
  location  z*-12
  direction  z
  up    y
  right    x*image_width/image_height
  scale    32
}

#local temp_light_1 = light_source
{
  0
  color rgb 1
  translate <-30, 30, -30>
}

#local temp_light_2 = light_source
{
  0
  color rgb 1
  translate <-30, 30, +30>
}

union
{
  object {temp_light_1}
  object {temp_light_2}
//  camera {temp_camera_1}  // doesn't work!!!
}

//object {temp_camera_1}  // doesn't work!!!
camera {temp_camera_1}  // works!!!

Changing this behavior would make it possible to more easily apply transformations to scene objects and the camera at the same time in situations where the scene’s frame of reference is in motion relative to the rest of the scene, for instance in animations.

I used POV-Ray to make an animation of my Morgan driving around a slalom course. (If you are curious, you can see the output on youtube under my user name, nojonushi.) To make the long swooping fenders I used Mike William’s SweepSpline macro.

The code rendered the 1189 frames in one go with no problems. But the wheels in that animation do not rotate, so I then added code to rotate the wheels. In the calculations I added I used a #while loop to step through the spline containing the route coordinates and total up the distance traveled. Running POV-Ray on this file produced a random number of images and then issued an error, e.g.

 0:00:00 Processing Frame 456 of 1189
 0:00:00 Parsing

File: mogslalom.pov Line: 1918
Parse Warning: Patch objects not allowed in intersection.
File: mogslalom.pov Line: 2988
File Context (5 lines):

                object {
                SweepSpline(TFSpline,

Parse Error: Identifier expected, incomplete function call or spline call found instead.

Most of the parameters for the macro are missing. But this is after successfully generating, in this case, 455 images.

I have attached a text file with set-up and sample code that has given the error on two different machines.

I got a 29023 Segmentation fault ... but it was NOT repeatable. I reran the render job repeatedly and it displayed appropriate error message. I had renamed a texture identifier but missed an occurrence inside texture_map.

FYI: I did a build off the depot last evening.(21:13)