another memory allocator change

• disabled the TCMALLOC memory allocator (a suspected bug in tcmalloc small memory allocations caused a segmentation fault)
• alternatively a buggy x265 library might need replacing by Intel SVT-HEVC; for now reverted the memory allocator back to the standard GNU C malloc/calloc/realloc/free whilst testing another allocator: mimalloc
• recompiled the WebAssembly with the latest emscripten compiler (enabled the mimalloc support)

fine-tuning

• adjusted the client-side JavaScript clipSize zoom viewport size variable

a memory allocator change

• replaced the external JEMALLOC memory allocator with TCMALLOC (a bug in jemalloc caused a segmentation fault)
• recompiled the WebAssembly with the latest emscripten compiler

further fine-tuning

• refined the WebGL viewport pixel coordinate translation

fine-tuning

• improved the translation between the web browser mouse coordinates and the underlying FITS image pixel coordinates
• updated the mongoose C networking library to v7.12

ds9 region import & WCSLIB integration

• a new functionality: an initial support for importing ds9 region files (*.reg) with image/physical/wcs (fk5 only) coordinates and two types of shapes: circle and point (hint: a menu setting FITS / import ds9 region)
• incorporated the WCSLIB library server-side (in the CSV export FORTRAN code ) as well as in the client-side JavaScript (calling the WASM-compiled C code), which replaces a custom implementation of the WCS conversion routines and provides a better compatibility with ds9
• a minor fix to the CSV export functionality (fixed the RA string parsing in the server C code)

a bug fix

• corrected the display of RA/DEC coordinates (for example when moving the mouse over the FITS image), which brings the beta v5 into line with FITSWebQL v4 and ds9

P-V Crosshair

• an improved P-V diagram: an all-new crosshair with a tooltip (hint: hover a mouse over the P-V diagram)

spectrum binning 2

• spectrum binning: replaced the Largest Triangle Three Buckets downsampling with true binning (averaging adjacent values)

spectrum binning

• added a new spectrum binning functionality (see a menu setting Preferences / spectrum binning)