graphite-addon-loader

The addon_loader.lua script aims to load external programs or scripts as Graphite add-ons.

Prerequisites

• Graphite > v3-1.8.8

Enable Graphite loading add-ons

Get addon-loader

• Download the script file addon_loader.lua
• Put this script into a directory of your choice, preferably in a non-volatile directory with a well-formed path

Configure Graphite

You have to go to File -> Preferences -> Startup and add the lua script addon_loader.lua. Don't forget to click on Save Config. and restart Graphite.

Graphite will start and execute this script. A menu Externals should appear.

Add add-ons

You can add many add-ons at once by choosing an add-ons directory via the menu Externals -> Manage add-ons -> Parameters. The directory will be scanned (browsing all subdirectories) and all executables containing _addon in their names will be recognized as add-ons.

Synchronize

When you add or remove an add-on or change its interface, you have to synchronize Graphite with these modifications. You can update your add-ons by via the menu Externals -> Manage add-ons -> Synchronize and Quit. One this command applied Then, you have to restart Graphite manually.

Try with an existing add-on

As you probably don't have any add-ons at hand, we've put together a series of small add-on examples for you. You can go to:

https://github.com/ultimaille/graphite-addon-examples/releases/tag/v2.0

You will find binary of add-ons that you can add to Graphite.

Note: Mac OS binaries are not signed, but we hope that this will be the case in the future.

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Create add-ons

To turn a program into an add-on recognizable by addon_loader, your program must:

• Have _addon in its name, for example: my_program_addon
• Respond to the --show-params argument, returning program parameters as EPF format
• Accept to be called with arguments as the following format: k1=v2 k2=v2 ... kn=vn with ki the parameter name and vi the value of the parameter (e.g: my_program param_string=hello param_bool=true param_int=1 ...)

Note: for the programs written in C++, we encourage you to use https://github.com/ultimaille/param-parser. This micro library help you to declare parameters and return EPF format when --show-params is requested.

You will find add-on source C++ examples at https://github.com/ultimaille/graphite-addon-examples.

How Graphite recognize add-ons ?

To enable Graphite loading add-ons and generate the appropriate user interface (UI), it is necessary to present program parameters in a specific format that can be read and understood by Graphite. Let's call this format EPF format for External add-on Format / Expose Parameter Format.

This format is obtained by Graphite when executing addon_loader.lua by calling a program with --show-params argument, returning program parameters as EPF format.

EPF format

EPF format is very simple and looks like this:

 #This file contains reflexion information for calling a binary file
name=param1;type=bool;value=false;possible_values=undefined;description=A bool;type_of_param=undefined
name=param2;type=double;value=0;possible_values=undefined;description=A double;type_of_param=undefined
...

Each line contains data about one parameter:

• name: parameter name (displayed as a label in UI)
• type: parameter type {int, float, double, bool, string, file, input}
• possible_values: a list of values to be selected if parameter is an enum
• description: a description of the parameter that can be displayed as a tooltip text in UI
• type_of_param: {basic, advanced or system} describe how the parameter should be appear in UI
• visible (optional): indicate whether the parameter is visible in the UI

Line that start with # are comments.