POV-Ray : Newsgroups : povray.beta-test : 16-bit PGM pigment and height field problems : Re: 16-bit PGM pigment and height field problems Server Time
4 Nov 2024 21:20:36 EST (-0500)
  Re: 16-bit PGM pigment and height field problems  
From: Mike Hough
Date: 2 Oct 2001 12:55:22
Message: <3bb9f17a@news.povray.org>
> Mike, your PGM file has a couple of problems.  First, xv thinks it's
> truncated (and pgmtoppm spins forever trying to read it, which backs up
> xv's assertion.)

The file was created by Bryce which can also read the image.  Paint shop pro
reports the image as being 128x128 both prior to and after opening.  POV-Ray
3.1 reads and reproduces the file correctly as well.  Short of counting each
entry in the map, it seems that it does have the number of values indicated
in the header.

> Second, the lines are too long: the pgm spec says lines
> must be 70 characters or less.

Although it does say this for writing files, it also says that programs that
read this format should be as lenient as possible, accepting anything that
looks remotely like a graymap.  POV-Ray 3.1 would except longer lines.

There may have been another problem with PGM files.  I seem to recall having
to remove the comments (text following # character) in order for the file to
parse.  I would double check it but my beta has expired.


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