Available for initial testing is the new Essence operating system, which comes with its own kernel and graphical user interface. The project has been developed by one enthusiast since 2017, created from scratch and is notable for its original approach to building a desktop and graphics stack. The most notable feature is the ability to divide windows into tabs, which make it possible to work in one window with several programs at once and group applications into windows depending on the tasks being solved. The project code is written in C++ and distributed under the MIT license.
The window manager works at the level of the operating system kernel, and the interface is created using its own graphic library and a software vector engine that supports complex animated effects. The interface is fully vector and automatically scales for any screen resolution. All style information is stored in separate files, which makes it easy to change the appearance of applications. OpenGL programmatic rendering uses code from Mesa. Multiple languages ββare supported, and FreeType and Harfbuzz are used to render fonts.
The kernel includes a task scheduler with support for multiple priority levels, a memory management subsystem with support for shared memory, mmap and a multi-threaded memory pager, a network stack (TCP / IP), an audio subsystem for mixing sounds, VFS and an EssenceFS file system with a separate layer for data caching . In addition to its own FS, drivers for Ext2, FAT, NTFS and ISO9660 are provided. It supports the removal of functionality into modules with the ability to load such modules as needed. Drivers prepared for ACPI with ACPICA, IDE, AHCI, NVMe, BGA, SVGA, HD Audio, Ethernet 8254x and USB XHCI (storage and HID).
Compatibility with third party applications is achieved with a POSIX layer sufficient to run GCC and some of the Busybox utilities. Of the applications ported to Essence, the Musl C library, the Bochs emulator, GCC, Binutils, FFmpeg and Mesa are noted. Essence-specific graphical applications include a file manager, text editor, IRC client, image viewer, and system monitor.
The system can run on legacy hardware with less than 64 MB of RAM and takes up approximately 30 MB of disk space. To conserve resources, only the active application runs, and all background programs are suspended. Loading takes only a few seconds, and the shutdown is almost instantaneous. The project daily publishes new ready-made builds suitable for testing in QEMU.
Source: opennet.ru