Zynthian MOD-GUI Guide

1 How to create modgui images for MOD-UI

1.1 What is MOD-UI?

MOD-UI is a open-source web-gui for LV2 plugins. It is written and maintained by http://www.moddevices.com. They sell a very nice effect, which uses lots of free LV2-plugins and is configurable via USV-ethernet. MOD-UI is open-source, too, so Zynthian uses it also as one of several usable engines. In MOD-UI you can drag & drop LV2-plugins of several type (modulators, equalizer, generators (=> synths), ... and connect them together in a way which is realy intuitive and easy.

1.2 What is a modgui?

As I said: MOD-UI is based on LV2 plugins. For interacting with the LV2-plugin the default icon in MOD-UI is a tin (looks like a tin for fish). But plugins also have paramters and they should look not the same. Here is the point where modgui is used. In fact it is an addition to the description of the plugin plus some graphic data and stylesheets. The description is written down in text files in the Turtle-Syntax.

1.3 What is MOD-SDK?

Writing Turtle files is (IMHO) not really easy. Also reusing and creating nice looking images for different plugins with different parameters is not easy to write down in Turtle. So MOD has created a SDK. This is an additional server (like the MOD-UI server) which has several templates for creating nice looking modguis for plugins. MOD-SDK should be installed on Zynthian but it is not enabled. Also if it is not installed: it is not difficult to get it installed and running.

1.4 How to create a modgui?

First check if MOD-SDK is installed. Currently you need to login via ssh to your Zynthian. Than try systemctl start mod-sdk. If this starts, you should be able to go to http://<YOUR-ZYNTHIAN-IP>:9000. If not here is a recipe for installing mod-sdk on your Zynthian:

 cd /zynthian
 git clone https://github.com/dcoredump/zynthian-recipe
 cd zynthian-recipe/recipe
 sh mod-sdk.sh

1.4.1 The easy way

Ok. This is really easy: Go to http://<YOUR-ZYNTHIAN-IP>:9000. You see a selection-box with Select-Bundle. Choose the LV2-plugin (bundle) which you want to edit. You get a page with an index for sub-pages and some information about the selected plugin. Now you can walk through the sub-pages.

The most important page is the 2nd: Icon. When you select it you get a button named Launch Wizard. After pressing you get a sub-window where you can choose the box-style, box color, knob-style and panel-layout. I think trying around is the best way to learn what is useful and what not. You should have in mind that plugins have different parameters and mapping all or nothing to knobs and/or select boxes may not be the best way. So I think going to the next step (button Next) shows all the parameters and how they will be mapped to knobs. Think about which parameters will be useful to have directly on top of the plugin and which not and map them (e.g. I will try to map Volume to the first button if it is available). Perhaps you have to switch Back and Next several times until you get what you want. On the last step you can create the screenshots. Do this if you like - but you can also do this later. Now press Finish and you get back to the main pages.

If you switch to the next sub-page (Icon screenshot) you can generate the screenshots, too.

On the sub-page Settings you can advise the initial parameters for this plugin.

And now: Deploy - a very nice feature. If there is not the right IP-address (includeing the port!) of your Zynthian in the text field: edit this field! After deploying you cannot see the new icons. You first have to reload MOD-UI/mod-host.