NEWS

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fmesher 0.6.1.9000

fmesher 0.6.1

New features

• Add fm_subset() method for constructing a subset of a mesh based on a set of triangle (for fm_mesh_2d) or tetrahedron (for fm_mesh_3d) indices. (version 0.5.0.9003)
• Add fm_zm()/fm_zm_input()/fm_zm_target() methods for adding/removing/unifying the Z/M dimensions of coordinate matrices and sf objects (version 0.5.0.9012)
• New method new_fm_int() to construct tibbles with the same output format as the fm_int() method, for user-defined integration schemes (version 0.5.0.9013)

Improved features

• Add bary=fm_bary() information to fm_subdivide() output, mapping the new mesh locations to the original mesh locations, e.g. for interpolating functions from the original mesh to the new mesh (version 0.5.0.9002)
• Speed up fm_int() for polygons by bulk pre-computing fm_bary() information instead of separate calls in fm_vertex_projection() (version 0.5.0.9004)
• Handle heterogeneous sf geometry XY/XYZ dimensions in fm_bary()/fm_basis() via fm_zm() method that is called by fm_onto_mesh() and fm_unify_coords() to promote XY to XYZ when needed, before calling sf::st_coordinates(), as sf::st_coordinates() otherwise fails. (version 0.5.0.9005)
• Allow fm_int.fm_mesh_1d() to handle lists of matrices (for interval integration) and vectors (sums over point sets), for more flexible blockwise integration and summation schemes. (version 0.5.0.9007)
• Allow fm_int.list() to include non-domain variables in the output object, e.g. for including per-transect covariates in the integration scheme. (version 0.5.0.9008)
• Allow fm_int() for numeric/character/factor/fm_mesh_1d to handle nested list samplers (version 0.5.0.9009)
• Drop gsl package dependency by using a native C++ implementation of the associated Legendre polynomials and spherical harmonics via fm_raw_basis() (version 0.5.0.9014)

Bug fixes

• Make fm_subdivide() store the indexing information for the original mesh locations in $idx$loc (version 0.5.0.9001)
• Correct off-by-one indexing error in $graph$vt triangle indices (version 0.5.0.9002)
• Propagate correct crs information in fm_bary_loc() for 2D spaces (version 0.5.0.9005)
• Fix bugs in fm_mesh_intersection() and fm_bary() C++ code that caused incorrect behaviour for locating points on meshes on subsets of the sphere. Also allow fm_mesh_intersection() to generate non-Delaunay triangles, allowing the generated meshes to be used for stable integration schemes (version 0.5.0.9006)
• Handle the weights argument in fm_basis.matrix() and fm_basis.Matrix() when full = FALSE (version 0.5.0.9013)

Deprecation updates

• Increased deprecation warning and error messages for old unsupported methods (version 0.5.0.9015)
• Removed exports of deprecated CRSargs methods (version 0.5.0.9015)

fmesher 0.5.0 (2025-07-07)

New features

• Add fm_area() method for fm_segm area calculations (version 0.4.0.9002)
• Make fm_nonconvex_hull() a unified function for "fm" and "sf" construction methods and input/output formats, with default method "fm" and output format "sf", making fm_nonconvex_hull_inla() deprecated. (version 0.4.0.9004)

Improved features

• Rename fm_mesh_components() to fm_components() and add support for fm_segm objects (version 0.4.0.9001)
• Add support for polygon output in fm_as_sfc() for closed boundary fm_segm objects (version 0.4.0.9002)
• Add support for fm_segm as boundary input to fm_hexagon_lattice() (version 0.4.0.9005)
• Add fm_segm integration support for fm_mesh_2d objects in fm_int() (version 0.4.0.9005)

Bug fixes

• Fix indexing bug in fm_basis.fm_mesh_1d() for degree = 2 and NA locations (version 0.4.0.9003)
• Detect unnamed sfc objects in fm_int() for multi-domain integration and give an error, as the user must provide a geometry name (version 0.4.0.9005)
• Check that every fm_int() sampler for domain lists has at least one corresponding domain (version 0.4.0.9007)
• Remove support for character .block information in fm_int()/fm_cprod(), forcing the use of integer, as character could lead to incorrect block aggregation output ordering. The equivalent information is now available in .block_origin. Also clean up of fm_cprod() and sf handling (version 0.4.0.9006)

fmesher 0.4.0 (2025-06-12)

New features

• Add fm_hexagon_lattice() for creating regular hexagonal lattice points to use with fm_mesh_2d(), from Man Ho Suen (version 0.3.0.9001 and 0.3.0.9006)
• Add fm_mesh_components() method for extracting (dis)connected components from 2D and 3D meshes (version 0.3.0.9005)
• Add fm_collect() method for creating a collection of meshes of the same type (version 0.3.0.9009)

Improved features

• Construct better representative boundary points for mid data of fm_mesh_1d for degree = 2, boundary = "free" (version 0.3.0.9002)
• Add argument delaunay to allow non-Delaunay mesh construction in fm_subdivide() (version 0.3.0.9003)
• Better handling of line integration when triangle edges and line transects are co-linear (version 0.3.0.9004)
• Add support for order > 2 for fm_fem.fm_mesh_1d() (version 0.3.0.9011) and generally for fm_matern_precision() (version 0.3.0.9012)
• Add argument units to fm_crs() to allow setting the length unit for the CRS on creation/extraction (version 0.3.0.9013)

Bug fixes

• Improved bug fix in fm_mesh_2d_inla() from 0.2.0.9014 to allow negative offset in the second layer when the inner layer is specified only through a boundary polygon (version 0.3.0.9007)
• Bug fix for fm_mesh_2d_inla() to ensure S2 manifold meshes covering the entire sphere aren't accidentally limited to a subset of the globe (version 0.3.0.9008)
• Handle colour palettes with fewer than requested colours in fm_generate_colors() (version 0.3.0.9008)
• Fix bug in fm_detect_manifold() that caused it to return "R2" for "S2" and "M2" manifolds (version 0.3.0.9010)
• Fix bug in fm_as_mesh_3d_list() that caused it to return the mesh surface as an fm_mesh_2d object instead of the full fm_mesh_3d object (version 0.3.0.9014)

fmesher 0.3.0 (2025-03-18)

New features

• Convert fm_bary() output to a dedicated fm_bary class, with elements 'index' (index of the containing simplex) and 'where' (matrix of barycentric weights). (version 0.2.0.9001)
• Add fm_bary_simplex() generic method to extract the simplex vertex indices for an fm_bary object. (version 0.2.0.9001)
• Add fm_bary_loc() generic method for converting fm_bary information to Euclidean coordinates (version 0.2.0.9005)
• Add support for fm_mesh_3d and new fm_lattice_Nd class (version 0.2.0.9008 and 0.2.0.9011)
• Add fm_assess() method, replicating the old INLA::inla.mesh.assessment() method (version 0.2.0.9010)
• Add R implementation of fm_qinv() for computing sparse matrix partial inverses (version 0.2.0.9010)

Improved features

• Handle NA location inputs to fm_basis.fm_mesh_1d() (version 0.2.0.9002)
• Simplify fm_basis object creation, and add custom_classes developers vignette (version 0.2.0.9004)
• Add fm_basis(mesh, loc = fm_bary(mesh, ...)) support for fm_mesh_1d and fm_mesh_2d objects (version 0.2.0.9006)
• Add list() input support for fm_int.numeric, to allow multiple integration blocks for discrete domains (version 0.2.0.9012)
• Add mappings and defs support to the geom_fm.fm_mesh_1d() method, allowing separate control of the ggplot2 aesthetics for basis functions, knots, and function evaluations (version 0.2.0.9013)
• Add support for character block input to fm_block methods, to automate multi-domain integration support from fm_int() (version 0.2.0.9017)

Bug fixes

• Make fm_try_callstack() more robust against large callstack sizes; solves "C stack" crash issue for inla() error reporting (version 0.2.0.9007)
• Fix fm_bbox.fm_mesh_2d() bug for "S2" and "M2" manifold meshes (version 0.2.0.9008)
• Fix bug in fm_rcdt_2d_inla() that lead to ignoring the quality.spec argument (version 0.2.0.9009)
• Fix bug in fm_mesh_2d_inla() that improperly ignored negative offset values when creating meshes based on only boundary information (version 0.2.0.9014)
• Minor bugfix for print.fm_segm() for empty fm_segm objects (version 0.2.0.9015)
• Bugfix for fm_mesh_2d_inla(interior = ...) where part of the code incorrectly assumed interior would be a list. Now converts a list into a single fm_segm object (version 0.2.0.9016)

Deprecation updates

• Remove long deprecated inla.mesh etc legacy methods; need to explicitly convert old objects. Retaining the inla.mesh etc class suffixes for now. (version 0.2.0.9001)

fmesher 0.2.0 (2024-11-06)

New methods

• Add print methods for fm_basis and fm_evaluator objects (version 0.1.7.9003)
• Add fm_manifold_get() generic method to extract manifold information from general objects, so that external objects can implement their own manifold information storage (version 0.1.7.9005)
• Add fm_crs_plot() method for plotting fm_crs objects with optional graticules and Tissot indicatrices (version 0.1.7.9010)

New method options

• Add full argument to fm_basis() to toggle between matrix and full fm_basis object output (version 0.1.7.9002)
• Add loc plotting option to geom_fm.fm_mesh_2d and modify the ggplot mapping interface for interior and boundary segments in the same method (version 0.1.7.9009)
• Add format="loc" argument to fm_as_sfc.fm_mesh_2d() for converting mesh node coordinates to sfc_POINT format (version 0.1.7.9009)

Minor updates

• Update documentation and vector coordinate inputs to fm_lattice_2d() to clarify input interpretation and ensure correct boundary orientation (version 0.1.7.9001)
• Add some length unit handling to fm_crs_bounds() (version 0.1.7.9008)
• Add control argument max_batch_size to fm_bary.fm_mesh_2d(), that can be supplied via fm_basis(), for optional override of the default maximal batch calculation size, see #14 (version 0.1.7.9011)

Deprecation updates

• Remove sp objects from fmexample data. Use fmexample_sp() to access them if needed (version 0.1.7.9004)
• Move sp dependency to Suggests, and remove inlabru dependency (version 0.1.7.9006)
• Further sp use protection (version 0.1.7.9007)
• Increased deprecation warning and error messages for old unsupported methods

fmesher 0.1.7 (2024-07-01)

• Fix regression bug in fm_manifold() that made it ignore all but the first given type options. See #16 (version `0.1.6.9001)
• Fix plot.fm_mesh_2d vectorisation bug (version 0.1.6.9002)
• Add new fm_subdivide() method for fm_mesh_2d meshes (version 0.1.6.9003)

fmesher 0.1.6 (2024-06-14)

• Fix for hiding away-facing triangle edges in plot.fm_mesh_2d() and lines.fm_segm().
• Fix duplicated fm_unify_coords.sf() method. Thanks to Pablo Paccioretti for debugging and reporting, see #13 (version 0.1.5.9001)
• Use batched fm_bary.fm_mesh_2d() computations for data sizes of 2e5 and upwards. This improves performance of fm_basis()/inla.spde.make.A() for large data sets, see #14 (version 0.1.5.9002)
• Automatically convert raw sfc samplers objects to sf objects in fm_int.list() (version 0.1.5.9003)
• Detect and warn about unsupported use of fm_segm objects in fm_int.list() (version 0.1.5.9004)
• Add fm_basis() and fm_fem() support for fm_tensor function spaces (version 0.1.5.9005)
• Add fm_CRS() support for terra objects (version 0.1.5.9006)

fmesher 0.1.5 (2023-12-20)

• Fix bug in fm_matern_sample() that prevented the use of a non-NULL loc argument. For earlier versions, the workaround is to make a separate call to fm_evaluate() after calling fm_matern_sample().
• Improve speed of fm_block_log_shift() by an order of magnitude for multi-block cases.
• Fix bug in plot.fm_mesh_2d for meshes with 2D coordinate storage (version 0.1.4.9002)

fmesher 0.1.4 (2023-10-28)

• Work around std::get<variant>() lack of support for MacOS < 10.14.

fmesher 0.1.3 (2023-10-18)

• Fix bug in fm_rcdt_2d_inla() that gave different defaults for the extend and refine arguments when equal to TRUE, that should be treated the same as list() (version 0.1.2.9001)
• Fix bug in fm_rcdt_2d_inla() to properly update n basis counter element when removing unused vertices. (version 0.1.2.9002)
• Fix bug giving a spurious warning about inconsistent is.bnd for empty fm_segm objects, and inconsistent grp vector lengths. (version 0.1.2.9003)
• Convert some of the old potentially unsafe C++ pointer methods to type safe C++17 features

fmesher 0.1.2 (2023-08-25)

• Various documentation improvements, in particular for INLA compatibility
• Modify mesh refinement tests to directly check the refinement criteria instead of the specific mesh result, to account for differences in floating point behaviour on M1 processors.
• Modify tests of non-mesh-generation features to use precomputed meshes or meshes with stable properties
• Protect against invalid tv inputs
• Revert from \text{} to \textrm{}, as AMS extensions are only supported from R 4.2.2 (https://www.stats.bris.ac.uk/R/doc/manuals/r-devel/R-exts.pdf 2023-08-24, page 90), and CRAN oldrel for macOS is 4.2.0, not 4.2.3

fmesher 0.1.1 (2023-08-18)

• Simplify LICENSE information in the R package DESCRIPTION
• Fix example for legacy plot_PolySet method
• Fix C++ unused-variable warning detected by clang-tidy version 16.0.6
• Add workaround for sf::st_buffer not supporting negative distance for s2 with longlat coordinates. Fixes #5

fmesher 0.1.0

• Full conversion of the fmesher interface from the standalone binary in R-INLA (https://www.r-inla.org) to an interface powered by Rcpp (https://cran.r-project.org/package=Rcpp)
• Tools for 2D and 1D function spaces, see fm_mesh_2d() and fm_mesh_1d()
• Tools for CRS handling see fm_crs() and fm_transform()
• Plotting support for base graphics, rgl, and ggplot2
• Added basic GMRF tools, see fm_matern_precision()

fmesher 0.0.9

• Basic fmesher library I/O interface
• Added a NEWS.md file to track changes to the package.