INX extension descriptor format

Introduction

In order for Inkscape to make use of an external script or program, you must describe that script to inkscape using an INX file. The INX file is an XML file with Inkscape-specific content that can be edited in a plain-text editor.

The INX file allows the author to:

  • Specify what type of extension it is, for example input, output, or effect

  • Identify which interpreter should be used to run the extension

  • List dependencies; files or other extensions required for operation

  • Define parameters that can be set in the extension

  • Create a GUI with control widgets for those parameters

  • Add a submenu to the Extensions menu for the extension to reside in

  • Label strings for translation

  • Chain extensions

  • Etc

Nothing beats a working example, and Inkscape includes a great number of extensions with INX files that you can read. To find the location of your Inkscape extensions directory, where included extensions and their INX files are located, look in the System pane of Inkscape Preferences, under “Inkscape extensions”.

Translation of extensions

Inkscape extensions repository

When extensions are included in the Inkscape Extensions Repository, various scripts will scan each INX file for translatable text and prepare translation files for others to translate.

Use translatable="no" to make an item (e.g. a unit name) untranslatable.

Third party extensions

Third party extensions can set their own translation files by setting up their own unique translation domain.

Example:

<inkscape-extension translationdomain="my_extension" xmlns="http://www.inkscape.org/namespace/inkscape/extension">

Use the inx.its file from the Inkscape main repo and run xgettext my_extension.inx --its=inx.its -o my_extension.pot. This will generate the pot file, which you can distribute to translators. Use the .mo files generated from those in a special structure:

locale/
├── ar
│   └── LC_MESSAGES
│       └── my_extension.mo
├── as
│   └── LC_MESSAGES
│       └── my_extension.mo
├── az
│   └── LC_MESSAGES
│       └── my_extension.mo
...

If the files are, for instance, in .config/inkscape/extensions/my_extension/locale/<lang>/LC_MESSAGES/my_extension.mo, then an inx file at .config/inkscape/extensions/my_extension/my_extension.inx with the translationdomain my_extension will be translated in the interface.

The following three locations are recursively searched for “${translationdomain}.mo”:

  • the ‘locale’ directory in the .inx file’s folder

  • the ‘locale’ directory in the “extensions” folder containing the .inx file

  • the system location for gettext catalogs, i.e. where Inkscape’s own catalog is located

Attributes description

Attribute name

Allowed values

implements-custom-gui

New in version 1.0.

"true" | "false" (default)

If set to true requires an effect extension to implement custom GUI.

Hint

Implementation detail: The “extension is working” window is not shown for this kind of extensions. This means user interaction with the Inkscape interface is blocked until the extension returns, with no way for the user to abort the running extension! It is therefore absolutely essential that your extension provides the necessary visual feedback for the user and has proper error handling, to rule out any dead-locking behavior.

needs-document

New in version 1.0.

"true" (default) | "false"

If set to false an effect extension will not be passed a document nor will a document be read back (“no-op” effect). This is currently a hack to make extension manager work and will likely be removed/replaced in future, so use at your own risk!

needs-live-preview

"true" (default) "false"

If set to true in an effect extension, it will offer a “Live preview” checkbox in its GUI. When the user checks that box, it will run the extension in a “preview mode”, visually showing the effect of the extension, but not making any changes to the SVG document, unless the user clicks the Apply button. While “Live preview” is checked in the GUI, any changes that the user makes to parameters accessible in the GUI will generate an updated preview.

savecopyonly

New in version 1.2.

"true" | "false" (default)

If set to true in an output extension, it will limit the extension to being available only in the “Save a Copy” menu.

Example

<?xml version="1.0" encoding="UTF-8"?>
<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
  <name>{Friendly Extension Name}</name>
  <id>{org.domain.sub-domain.extension-name}</id>
  <dependency type="executable" location="[extensions|path|plugins|{location}]">program.ext</dependency>
  <param name="tab" type="notebook">
    <page name="controls" gui-text="Controls">
      <param name="{argumentName}" type="[int|float|string|bool]" min="{number}" max="{number}"
        gui-text="{Friendly Argument Name}">{default value}</param>
    </page>
    <page name="help" gui-text="Help">
      <param name="help_text" type="description">{Friendly Extension Help}</param>
    </page>
  </param>
  <effect>
    <object-type>[all|{element type}]</object-type>
      <effects-menu>
        <submenu name="{Extension Group Name}"/>
      </effects-menu>
  </effect>
  <script>
    <command location="[inx|extensions]" interpreter="[python|perl|ruby|bash|{some other}]">program.ext</command>
  </script>
</inkscape-extension>

More example INX files are available in the Inkscape distribution, which takes its files from the Inkscape Extensions Repository.

For a full list of currently supported interpreters, please see Supported Interpreters.

DTD XML schema

Warning

This section contains slightly outdated information.

The following XML schema may not fully describe the current INX file structure. The actual XML schema used is described in the next paragraph.

<!ELEMENT inkscape-extension (name, id, dependency*, param*,(input|output|effect),(script|plugin))>
<!ELEMENT input (extension, mimetype, filetype, filetypetooltip, output_extension?)>
<!ELEMENT output (extension, mimetype, filetype, filetypetooltip, dataloss?)>
<!ELEMENT effect (object-type|submenu?)>
<!ELEMENT script (command, helper_extension*, check*)>
<!ELEMENT plugin (name)>
<!ELEMENT name (#PCDATA)>
<!ELEMENT id (#PCDATA)>
<!ELEMENT item (#PCDATA)>
<!ELEMENT option (#PCDATA)>
<!ELEMENT dependency (#PCDATA)>
<!ELEMENT param (#PCDATA|page|item|option)*>
<!ELEMENT page (#PCDATA, param*)>
<!ELEMENT extension (#PCDATA)>
<!ELEMENT mimetype (#PCDATA)>
<!ELEMENT filetype (#PCDATA)>
<!ELEMENT filetooltip (#PCDATA)>
<!ELEMENT object-type (#PCDATA)>
<!ELEMENT command (#PCDATA)>
<!ELEMENT check (#PCDATA)>
<!ELEMENT dataloss (#PCDATA)>
<!ELEMENT helper_extension (#PCDATA)>
<!ELEMENT output_extension (#PCDATA)>
<!ELEMENT menu-tip (#PCDATA)>

<!ATTLIST check reldir (absolute|path|extensions|plugins) #REQUIRED>
<!ATTLIST command reldir (absolute|path|extensions|plugins) #REQUIRED>
<!ATTLIST command interpreter CDATA #REQUIRED>
<!ATTLIST dependency type (executable|extension) #REQUIRED>
<!ATTLIST dependency location (absolute|path|extensions|plugins) #IMPLIED>
<!ATTLIST dependency description CDATA #IMPLIED>
<!ATTLIST effect needs-live-preview (true|false) #REQUIRED>
<!ATTLIST effect implements-custom-gui (true|false) #IMPLIED>
<!ATTLIST effect needs-document (true|false) #IMPLIED>
<!ATTLIST page name CDATA #REQUIRED>
<!ATTLIST page gui-text CDATA #IMPLIED>
<!ATTLIST param name CDATA #REQUIRED>
<!ATTLIST param type (int|float|string|bool|notebook|path|optiongroup|color) #REQUIRED>
<!ATTLIST param min CDATA #IMPLIED>
<!ATTLIST param max CDATA #IMPLIED>
<!ATTLIST param max_length CDATA #IMPLIED>
<!ATTLIST param precision CDATA #IMPLIED>
<!ATTLIST param gui-text CDATA #IMPLIED>
<!ATTLIST param gui-tip CDATA #IMPLIED>
<!ATTLIST param gui-description CDATA #IMPLIED>
<!ATTLIST param scope CDATA #IMPLIED>
<!ATTLIST param gui-hidden CDATA #IMPLIED>
<!ATTLIST param appearance (minimal|) "">
<!ATTLIST submenu name CDATA #REQUIRED>

RELAX NG XML schema

The XML schema for INX files is available in the Inkscape extensions Git repository. This is a RELAX NG schema.