svgx - Man Page

svgx [-a] [-b rgb] [-f rgb] [-g geometry] [-h] [-l] [-n rgb] [-o path] [-p] [-s name] [-t type] [-T rgb] [-v] [-V] [-z] [-4] [-5] [-6] path

The svgx program extracts and converts gradients in an SVG file​. Unlike most of the other file formats handled by the cptutils package, SVG files may contain multiple gradients, so this program operates a little differently to the other programs in the package​.

There are 4 modes of operation: The default is to extract the first gradient found in the file, or one can specify --list to list the names of all gradients in the file; --select to extract the gradient with the specified name or --all to extract all of the gradients​.

The output format is specified by the --type option as listed below (in fact there are several aliases for each format: jgd for psp, ggr for gimp and so on)​. The svgcpt, svgcss3, svggimp, svggpt, svgmap, svgpg, svgpsp, svgpov, svgpng, svgqgs, svgsao, svgsvg programs are wrappers around svgx which use the --type switch to specify output type​.

Atypically, the input SVG file is a mandatory argument​. The program will write to stdout if the -o option is not specified except when -a has been specified: then files will be produced (with names taken from those of the gradients)​.

Note that some of the SVG conversions require that the en_US​.utf8 locale be enabled​. How this is done will depend on your operating system​. One would run

apt-get install locales
dpkg-reconfigure locales

on Debian-based systems, for example​.

In the following, all rgb specifications should be of the form red/green/blue where the colour components are integers in the range 0 to 255​.

-a,  --all

Extract all gradients, which will have filenames derived from the gradient names​. If this option is used then the argument of the --output option will be interpreted as the output directory​.

-b,  --background rgb

Set the background colour of cpt output​.

Note that this only modifies the "background" field in the output cpt file, it does not affect the transparency (see the --transparency option in that regard)​.

--backtrace-file path

Specify a file to which to write a formatted backtrace​. The file will only be created if there is a backtrace created, typically when an error occurs​.

--backtrace-format format

Specify the format of the backtrace written to the files specified by --backtrace-file, one of plain, xml or json​.

--comments-read path

Read the comments from the specified path and add them to the output gradient​.

The format is simply a plain text multi-line document without any comment delimiters (those will be added by the program)​.

--comments-retain

Use the comments in the input file as the comments for the output file​.

--comments-generate

Create a comment with summary data (the date of creation, name and version of the cptutils package) in the output file​.

-f,  --foreground rgb

Set the foreground colour of cpt output​.

-g,  --geometry widthxheight

Specify the size of the PNG image or SVG preview in pixels​.

-h,  --help

Brief help​.

-l,  --list

List the names of all gradients in the file​.

-n,  --nan rgb

Set the NaN (no data) colour of cpt output​.

-o,  --output path

Write the output to path, rather than stdout​.

If the --all option is specified then the path argument must be a directory (which exists) and the output files will be written into this directory​.

-p,  --preview

Include a preview in the SVG output​. See also the --geometry option​.

--strict

Do not create files which break limits of the format specification​. In particular, do not create POV-Ray headers with more than 255 stops, do not create Tecplot maps with more than 50 points​.

-s,  --select name

Extract the gradient with the specified name, see the --list output for a list of possible values​.

-t,  --type format

Set the output format, which should be one of cpt, css3, ggr, gpt, map, psp, pov, png, qgs, sao or svg​.

-T,  --transparency rgb

When converting to a format which does not support transparency, replace the transparency with the specified rgb colour​.

-v,  --verbose

Verbose operation​.

-V,  --version

Version information​.

-z,  --z-normalise

Normalise the z-values in the cpt output into the range 0/1 and add a RANGE directive​. This is the form used in GMT master files​.

This option requires that output cpt version is at least 5​.

-4,  --gmt4

Use GMT 4 conventions when writing the cpt output: the colour-model code is uppercase, and the colours are separated by spaces​.

This is incompatible with the -5 and -6 options of course​.

At present this option is the default, but that will change at some point​. So specify this option if your use of the output depends on the GMT 4 layout (consumed by a custom parser, for example)​.

-5,  --gmt5

Use GMT 5 conventions when writing the cpt output: the colour-model code is lowercase, and the colours are separated by a solidus for RGB, CMYK, by a dash for HSV​.

This is incompatible with the -4 and -6 options of course​.

-6,  --gmt6

As the -5 option, but allows the HARD_HINGE and SOFT_HINGE directives in place of the explicit HINGE = directive​.

This is incompatible with the -4 and -5 options of course​.

Inspect an SVG file for gradients:

svgx -v -l old​.svg

Extract the gradient "Sunny Road" from the same SVG file, converting the result to cpt: (note that the gradient name needs to be quoted)

svgx -v -t cpt -s "Sunny Road" -o sunny_road​.cpt old​.svg

Extract all of the svg gradients from the file kittens​.svg and give each of them a preview:

svgx -v -t svg -a -p kittens​.svg

An ill-formed SVG gradient may be translated to rubbish while not reporting an error​.

When converting between types in several calls to different programs, one should note that the SVG format preserves the alpha channel, but will coerce the range to [0, 100]​. So converting from cpt to pg via cptsvg and svgpg one loses the cpt range information, while using cptpg will perserve it​. Conversely, converting SVG to pg via svgcpt and cptpg will lose the alpha channel, while svgpg will not​. This is the reason for the apparent duplication of functionality in the package​.

J​.J​. Green

cptsvg(1), gimpsvg(1), pspsvg(1)​.