WebGL GLSL off-load to CDN

• asynchronous (non-blocking) fetching of WebGL GLSL shaders from the Content Delivery Network (CDN) in the client-side JavaScript
• further reduced the compressed size of the initial web page response down to 1.73kB by off-loading the GLSL shaders to the CDN

reduced web page loading times

• switched to a versioned Font Awesome Kit in order to take advantage of a browser cache
• compress the main web page response, reducing the trasmitted size from 173kB to 35kB

page loading speed-ups

• removed fetching of the binned PNG background image from the JVO server whilst the FITS dataset is being loaded (saves several hundred kilobytes in Internet traffic)
• removed preloading of the metadata for three MP4 help video files (saves three HTTP requests to the CDN)
• optimised loading from the browser cache of the zero-md JavaScript library + dependencies, used to display the CHANGELOG

even faster web page loading

• further improved asynchronous loading of WebAssembly

faster web page loading

• asynchronous (non-blocking) loading of WebAssembly to speed up the initial web page loading

a stable release (out of beta)

• changed the display of the approximate size of FITS cut-outs to the IEC binary format (i.e. MiB, GiB, TiB, etc.)
• switched the display of the FITS file size to IEC binary
• improved automatic hiding of the newly-opened empty tab upon performing FITS cut-outs (browser dependent)
• re-wrote the server-side real-time WebSocket communication between the server and the web browser (replaced the mongoose C networking library with a custom C code loosely based on libmicrohttpd_ws)
• added reference counting to the FORTRAN FITS dataset derived type
• re-compiled the WebAssembly with the latest emscripten compiler
• out of beta into stable operation and maintenance, receiving bug fixes, tweaks and improvements

maintenance

• fixed a "bit rot" in the FORTRAN code (due to changed handling of implicit integer conversions by the gfortran compiler)
• shifted handling of </range/id> HTTP POST requests from mongoose to libmicrohttpd

a bug fix

• set the ZeroMQ port to 0 by default, hence assuming a single-server mode (the port can be specified in the config.ini file)
• corrected the P-V Diagram line length calculation inside a FORTRAN subroutine, added capacity checks to prevent potential out-of-bounds accesses

multi-dataset support

• added a 120s timeout to libmicrohttpd start-up flags, removed MHD_USE_TURBO
• replaced HTML5 Canvas with WebGL for streaming video frames
• removed the optional mongoose HTTP client part (using libcurl instead)
• added a CHANGELOG popup to the Help menu
• completed the multi-dataset support

bug fixes, WebSocket improvements

• corrected a problem with spectral lines (molecules) not being displayed after clicking F_REST in a web browser
• updated the server-side mongoose C networking library and replaced a UDP wake-up helper with a new mg_wakeup() function from mongoose
• the server-side WebSockets: separated the event loops for real-time spectra/video and PV-Diagram WebSocket messages
• .tar.gz FUGIN multiple-dataset partial FITS downloads compressed with a microtar ANSI C library
• added handling of HTTP 204 replies to the client-side JavaScript fetch_image_spectrum() function