lux image and panorama viewer: version 1.1.6 released

[kfj]

Dear all!

I've just released lux 1.1.6. The main change is that lux now uses highway as it's default

SIMD back-end, which should result in better performance for machines with AVX512f,

which Vc does not support. All builds which I publish on the download page will now be

done with highway. Apart from the change to highway, there were a few changes to the user interface.

 Here's a copy of the tag annotation I pushed with the 1.1.6 tag:

   with lux 1.1.6, highway is the default backend for SIMD operations.
    For i86 builds, there is no more dedicated AVX support with this
    back-end, only the (slow) 'fallback', SSE4.2, AVX2 and AVX512f.
    If you need dedicated AVX support, configure the build to use
    Vc and add the AVX flavour (-DUSE_HWY_LIBRARY=OFF -DUSE_VC_LIBRARY=ON
    -DFLV_AVX=ON). Performance of the SSE4.2 code is quite similar to
    dedicated AVX, and CPUs with AVX are getting increasingly rare,
    so I suppose it's okay to make this change. Up to the AVX2 ISA,
    Vc and highway produce quite similar performance, but for AVX512f,
    highway seems to perform better. For ARM builds, highway is the
    only option producing native ARM SIMD code anyway. Other architectures
    should also rceive native SIMD code with highway, but I have no test
    results confirming that.
    Apart from that, there were some bug fixes, and some changes to the
    user interface. lux can now do 'focused zoom', a zoom which is centered
    on the current mouse position. For mouse-wheel-mediated zoom, this is now
    the default, for vertical-secondary-button-click-drag it's optional.
    The behaviour can be switched on/off with the CL arguments scw_focused_zoom,
    and scvd_focused_zoom, respectively. Single click processing was also
    changed: a single primary-button click will stop an active auto-pan,
    but it won't start it (as it did previously). To start auto-pan with the
    mouse, there's a new gesture: the 'slap' or 'spin' gesture. It's a
    primary-button single-click executed while the mouse is in horizontal motion.
    The depression and release of the mouse button have to be no more than
    300msec apart for this gesture, otherwise it's taken as a click-drag.
    A secondary-button single-click will now move the click position to view
    center. There are two keys for quickly doubling/halving the zoom factor:
    the 2 and 3 keys. This gives another route to quickly zoom to interesting
    detail: secondary-click on the detail, then press 2 repeatedly.
    The 'focused zoom' can 'act funny' near the zenith and nadir because the
    viewer maintains the vertical. For work near zenith and nadir, it can be
    preferable to 'release the vertical' (F2). To 'regain the vertical', you
    can now use the 'J' key, which sets camera roll to zero, and pressing F2
    again after that will re-lock the vertical.

Enjoy!

Kay