Sigma OS

Sigma OS, also known as Project Sigma, was an operating system project developed during October 2022 during the series of operating systems that led to Steel OS 1.0 in late 2022. Sigma OS was cancelled later that same month, due to how ambitious it was. 39 builds of Sigma OS are known to exist, all for "Sigma OS 1.0". Sigma OS was developed by SteelsOfLiquid, who later developed Steel OS. Sigma OS was perhaps the most ambitious OS project developed by SteelsOfLiquid prior to his work on Steel OS 2.0, however, Sigma OS contained features that have yet to be added to Steel OS, such as integrated multi-language support.

## Features

Sigma OS contained many features during the short lifespan of it's development. To summarize, Sigma OS contained full vector graphics, a dynamic sound scheme, motion-based backgrounds, multiple visual themes, and support for multiple languages inside of one project.

### Full Vector Graphics

Sigma OS' graphics consisted almost entirely of SVG files, with the exception of the transparent boot shade, which was initially a PNG file. This set of graphics would later be seen in Plasma OS and OS/64, but were abandoned in November 2022 before the development of Steel OS 1.0 began, which saw the return to traditional bitmap graphics. Sigma OS took advantage of vector graphics to try and attempt to create a 3D-like interface, or at least one with skeuomorphic icons. This posed some disadvantages, however. As a result of the massive dimensions of the backgrounds, as they were converted to SVG files, resulted in a massive file size, which was larger than that of the Beta 1 Build 1927 build of Steel OS 3.

Vector graphics wouldn't be used in this way again after a certain point in the development of Plasma OS 1.0, and would be abandoned after use in a few prototypes of Steel OS. The last major use of graphics would be in OS/64 1.0 Codename "Macbeth" Build 198.

### Dynamic Sound Scheme

Sigma OS contained a full dynamic sound scheme resulting in most actions done in the system also playing a sound. For example, a chime would play if you clicked a main menu option, and logging on would play a dedicated chime that would later be reused as the startup sound in Steel OS, versions 1.0 Beta 2 to Steel OS 3 Beta 1 (as of 15 April 2023). The number of sounds in the project is rather large compared to other projects with dynamic sound schemes.

A dynamic sound scheme would later be used during the beta of Steel OS 3, this time containing sounds for various options, such as typing in a program which was keyboard-compatible, opening the main menu, and setting the wallpaper, among other things.

### Motion-Based Backgrounds

Sigma OS also contained a feature that was, and still is, popular among operating systems developed in Scratch: Backgrounds that would move with your cursor. Sigma OS took advantage of its full vector graphics and allowed the background to move whenever the mouse was moved. This feature affected all of the backgrounds that were supposed to be used in Sigma OS 1.0.

Motion-based backgrounds would later be experimented with during the development of Plasma OS, but would never be used after that. Steel OS won't ever get this feature due to the behavior of the background in programs such as Memo and Paint.

### Multiple Visual Themes

Sigma OS contained both a dark mode and a light mode, which were separate "visual themes". A setting was supposed to be introduced in order to allow this feature to be changed, but was never finished, and as a result, requires debug features in order to change the visual theme. Unlike Steel OS 3, Sigma OS 1.0 was not tolerant of the use of other visual themes, and as a result, Sigma OS could only accept the two visual themes it had pre-installed. This was due to the use of multiple languages, and unlike the plans for the Steel64 (Software) kernel, Sigma OS did not render text in a separate file from the program's window, meaning that as a result of the five languages and two visual themes in Sigma OS 1.0 Build 39, each Scratch 3 Sprite File had 10 sets of graphics.

Multiple visual themes would be experimented with in Steel OS 2.0's development (with the plans to try and retain the visual theme from Steel OS 1.0 and Steel OS 1.2 in Steel OS 2.0), but this feature would be scrapped for Steel OS 2.0. Multiple visual themes were introduced in Steel OS 3, with the introduction of various visual themes, including Steel OS Aero, Steel OS Metallic, and Steel OS Retro.

### Multiple Language Support

Sigma OS would have support for multiple languages, with Sigma OS 1.0 having support for English, Spanish, German, French, and Japanese, with planned support for Italian, Korean, and Portuguese later in development. This was done by translating the English interface of Sigma OS 1.0 (both in dark and light mode), and creating copies of each vector graphic sprite with the translated language. This feature was very ambitious (as very few, if not, any operating system(s) on Scratch had support for multiple languages), and would be what set Sigma OS apart from the rest of the prototypes leading to Steel OS 1.0.

Support for multiple languages would later be placed in the plans for Steel OS 4, which is planned to be the first version to use the Steel64 (Software) kernel. It should be noted that Japanese translations of Plasma OS and Steel OS 1.73 would later be developed and released.

## Fate

Sigma OS was, perhaps, the most ambitious of the pre-Steel OS 1.0 OS projects developed by SteelsOfLiquid. The project would later be abandoned in favor of Plasma OS, which was abandoned in favor of OS/64, which was abandoned in favor of one Steel OS prototype, which was abandoned in favor of another Steel OS prototype, which was abandoned in favor of Steel OS. During the development of a later version of Steel OS, SteelsOfLiquid planned on continuing development on Sigma OS, with the first objective being to convert the backgrounds to bitmaps, but this plan later fell through, and thus, Sigma OS became history.

It should be noted that due to the amount of features in Sigma OS, it could likely be picked up again in the future by SteelsOfLiquid, but with the development of Steel OS, this is rather unlikely.

## Usage

Sigma OS is sometimes used by SteelsOfLiquid to look for features to include in Steel OS, as it was used to rebuild the startup sound in Steel OS 1.0 Beta 2. It could likely become available on GitHub under SteelsOfLiquid's experiments repository, which is used to provide experimental prototype software that didn't get an official release. If this happens, it likely is to provide the ambitious project to Scratch operating system developers who want to try and improve their projects drastically, just like with Steel OS.

Apart from it's use by OS developers for reference, Sigma OS does not see use from the general public. This is due to the project never seeing a public release (it is documented due to SteelsOfLiquid's notes in Steel OS and SteelsOfLiquid's involvement in this wiki), therefore it never saw potential.

## Legacy

Sigma OS had a lot of features that would later be reused in versions of Steel OS, notably, the Sigma OS login sound was reused as the Steel OS startup sound, and later, the login sound, when Steel OS 2.0 introduced the lock screen.