robtk facilitates creating LV2 plugins UIs with emphasis to allow porting existing gtk+ plugin UIs.

robtk provides implementations for these existing gtk+ widgets:

• label
• separator
• push button
• toggle button
• radio button
• spin box
• text combo-box
• drawing-area

as well as gtk+ container and layout objects:

• horizontal box
• vertical box
• table layout

and additional widgets

• x/y plot area
• rgb/rgba image
• (volume, gain) slider
• multi-state button

A subset of gtk's functionality and widgets were re-implemented in cairo. On compile-time GTK+ as well as openGL variants of the UI can be produced.

The complete toolkit consists of header files to be included with the UI source-code and maps functions to the underlying implementation e.g. robtk_lbl_new() to gtk_label_new(). no additional libraries or dependencies are required.

Similar to widgets and layout, the event-structure and callbacks of robtk lean onto the GTK API providing

• mouse-events: move, click up/down, scoll
• widget-events: enter, leave
• widget-allocation: size-request, allocate, position
• window-events: resize, limit-size
• widget-exposure: complete and partial redraw

robtk includes LV2-GUI wrappers and gnu-make definitions for easy use in a LV2 project. Currently it is used by meters.lv2, sisco.lv2, tuna.lv2, mixtri.lv2, fil4.lv2 and setBfree