User:Xyzzy plover/sandbox

= Virtual Colour Systems = Virtual Colour Systems was founded in 1997 and is based in Glasgow, Scotland. It provides a free-to-use web application that provides virtual representations of a number of leading colour order systems: Colorcurve, Coloroid, DIN-6164, Munsell, Natural Colour System (NCS), Optical Society of America - Uniform Color Scales (OSA-UCS), and Swiss Colour Atlas (SCA-2541), colour ranges: British Standard 5252 (BS:5252), RAL 840-GL, and RAL-841HR, and colour specification systems: CIE, CIELab, and CIELuv.

Virtual Colour Atlas
The Virtual Colour Atlas is based on the 1990 Ph.D. thesis (A Colour Notation Conversion Program) by Neville Smith at the University of Teesside; the thesis describes a number of computer algorithms that enable conversion between various colour order systems (Coloroid, DIN-6164, Munsell, NCS and OSA-UCS) using the CIE system as a common intermediary. As the notational coordinates for these systems were either directly calculated from CIE values using equations (Coloroid, DIN-6164, and OSA-UCS) or had a number of their notational coordinates tagged with CIE equivalents (Munsell and NCS) then inter-system conversion was achieved by first converting from the source notation to CIE and then onto the target notation. Subsequent post-doctoral research resulted in the extension of the algorithm suite to include the Colorcurve and SCA-2541 colour order systems. The Colour Notation Conversion Program was developed using Turbo Pascal using on the MS-DOS operating system using a command line interface.

In 2005 an attempt was made to utilise the published algorithms with a graphical user interface (GUI) and a rendering engine to display the actual atlas samples. The algorithms were coded in VB.Net with a winforms based GUI running on the Microsoft Windows operating systems (version 1 of the application). Around that time Apple Mac was popular with what was deemed would be the primary target user base of such an application and, consequently, the application was never released as there was no easy way to make the application available on MacOS.

A second version of the application was successfully released in 2012 as a free-to-use web application. The core maths engines had been re-coded in C# and the GUI redeveloped using eXtensible Application Mark-up Language (XAML) and the Microsoft Silverlight runtime allowing the application to be deployed to the web and accessed using browsers that supported the Silverlight runtime extension (primarily: Chrome, Internet Explorer, and Safari). This was successful for a few years until Microsoft announced in 2015 that it would no longer continue development of the Silverlight engine and thereafter browser support began to rapidly decline until in 2021 Internet Explorer (that had been replaced by Microsoft Edge and was also near end-of-life) was the last remaining browser to support Silverlight and host version 2 of the Virtual Colour Atlas application.

The third and current version was developed in 2021 (released in August 2021) and retained the core algorithms coded in C#. The Silverlight GUI was replaced with Microsoft Blazor that uses web assembly (wasm) designed by the World Wide Web Consortium (W3C) to enable high-performance applications on web pages. Wasm is an open-standard maintained by the W3C and widely supported by browsers (including Chrome, Edge, and Safari); the version 3 front-end is therefore not dependent on the support of a single commercial company. The full solution effectively combines a C# back-end with a (mostly) Blazor wrapped HTML5 and javascript front-end running client-side for performance reasons.

The Virtual Colour Atlas (v3.0) is free to use for any purpose, requires no registration, is not feature locked, and contains not advertisements and is available here.