Gwyddion Files

Application:
- Translations updated: Czech, Russian.

Libraries:
- libgwyddion: ACF and PSDF fitting preset initial guesses were improved.
- libgwyddion: Function for checking for a regular lattice was added, able to
  handle rotation and some moderate defects.
- libgwyddion: gwy_raw_data_size() was updated for the new types added since
  2.65 and gwy_raw_data_size_bits() was added, useful for fractional sizes.
- libgwyddion: gwy_convert_raw_data() can handle 10byte x86 ‘extended’ floating
  point numbers.
- libgwyddion: Functions for filling an array with arithmetic progression and
  accumulation/rewind of array of counts were added.
- libgwyprocess: Function for the entire facet levelling procedure was added.
- libgwyprocess: Function for facet distribution computation was added.
- libgwyprocess: Function for polynomial scan line levelling was added.
- libgwyapp: Workaround was added for data browser drag'n'drop dropping wrong
  data in KDE Plasma in Wayland (and possibly other environments).
- libgwyapp: Log message handling can be modified using a new function.

Modules:
- Curve map fit (new): Fits general functions to curve map curves.
- Curve map volumize (new): Converts regular curve map data to volume data.
- XYZ Reduce (new): Reduces number of points in a XYZ data array. 
- XYZ 1D FFT filter (new): Performs FFT filtering in the XYZ data array,
  treating it as time series of equidistant values.
- PFM (new): Performs processing of vector Piezoresponse Force Microscopy
  data consisting of measurements in two perpendicular directions.
- Periodic translate (new): Translate image in the XY plane, treating it as
  periodic.
- Residue synthesis (new): Simulates surfaces resembling film residue after
  partial dissolution.
- HDF5: Support for Nanosurf NHF file format was added. Missing data units
  in EPFL files were corrected.
- Keyence: Wrong physical data scales and metadata in imported VK3 files were
  corrected.
- Nanoscope: Uses FV Lines for the number of scan lines in force volume data.
- Image export: Fonts with attributes like ‘Bold’ or ‘Italics’ are correctly
  loaded back from settings (instead of the font being reset to default).
  Round interpolation should make images in exported SVGs pixelated and masks
  should always be pixelated in SVG (as they are in PDF).
- Correlation length tool: Rewritten using the new self-consistent ACF paper.
  It also displays ACF and PSDF plots and lots of other improvements.
- Volume equiplane, Z-pos level: Crash for data with Z-calibration was fixed.
- Volume Crop: Missing coordinate units were corrected.
- Mutual Crop: Has a preview, can create new images and allows method
  selection.
- Statistical functions tool: Radial ACF subtracts the mean value
  automatically. Result not being always updated upon masking mode changes was
  fixed.
- Volume slice: Clear selection button was added. Fixed previews not
  correctly updating according to changing selection in some cases.
- Volume plane level: Zero mean value function was added.
- Lattice synthesis: Incorrect lattice scaling was fixed.
- Volume facet level: The progress bar actually works and the computation
  is cancellable.
- Fit terraces (image and graph) and volume and graph ASCII export: Output
  files are written with native EOLs, not always Unix.
- Facet analysis: Manual rotation of points works correctly again.
- Frequency split: A PSDF and filter shape plot was added.
- Grain filter: It now actually reads the ranges file with remembered ranges
  the for various quantities when run non-interactively.

Others:
- Compilation: configure now aborts when basic C99 maths functions like cbrt(),
  hypot() or erf() are not available. Gwyddion code has been using erf()
  unconditionally for many years so the change just makes it manifest.
- Compilation: Various auxiliary Python build scripts, generally used in builds
  from subversion, work with any Python version (2.7 or 3.x). Python checks
  were split into pygwy and interpreter for the scripts. Pygwy compiler and
  linker variables are now prefixed PYTHON2_ instead of PYTHON_.
- Plug-in proxy: Configuring with --disable-plugin-proxy now also prevents the
  installation of all plug-in support files.
- Python: Standalone Python module gwy initialises GTK+ more carefully, making
  it work at least to some degree without a display.