Twobjects quick reference

Twobjects is the result of migration taiwins from libweston , as libweston has many constrains, lacks of important features and has several severe bugs for daily users. Firstly I looked into wlroots and found it does not fit the design of taiwins, inspired by the two prior project. I created this library for faciliting the development of the wayland compositor. It is now merged inside libtaiwins.

Features

  • twobjects implements all the interfaces in the wayland.xml and several .. code-block:

    important protocols such as `xdg-shell` and `linux-dmabuf`.
    
  • twobjects is designed to backend agnositc, you can stack it on top of other .. code-block:

    backend implementation such as wlroots.
    
  • twobjects is designed to be autonomous. Unlike wlroots approach, which heavily exposes wl_signal from protocols so the users still has to write a layer of glue to use them. In twobjects, many of wayland protocols manages itself thus transparent to the backend developer. A good example is wl_data_device .

  • twobjects has built-in logging and profiling system and other utilites.

Building

Install dependencies:

  • meson

  • wayland

  • wayland-protocols

  • xkbcommon

  • libdrm

  • pixman

Commands for build:

meson build
ninja -C build

Commands for install:

sudo ninja -C build install

Getting started

Many protocols essentially implements a wl_global object like wl_compositor in the compositor, twobjects typically implements a corresponding type like tw_compositor . You can create the static global by using function like tw_compositor_create_global or allocate the memory yourself then use tw_compositor_init .

There are some cases where twobjects abstracts several protocols into common interface for users. For example, the tw_desktop_manager implements both wl_shell and xdg_shell and exposes tw_desktop_surface for the user, this is similar to the design of libweston.

For “middle-man” protocols like wl_data_device , the internals or managing wl_data_source , wl_data_offer is transparent to user. Users simply initialize the tw_data_manager for getting the clipboard in wayland.

Twobjects utilities

Twobjects implements utilies like matrix, cursor, logging and profiling functions for users. Check out the headers for usage.