NEWS

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grainscape 1.0.0

Dependency changes

• Migrated from raster/sp to terra/sf for all spatial operations:
  • terra and sf added to Imports;
  • raster and sp dependencies removed entirely.
• Vignette diagrams are now generated from code with DiagrammeRsvg and rsvg (added to Suggests); webshot2 is no longer needed for the vignettes and was removed from Suggests.

Breaking changes

• MPG(), patchFilter(), and ggGS() no longer accept RasterLayer inputs; pass SpatRaster objects (from terra) instead;
• corridor(), distance(), and point() no longer accept SpatialPoints inputs; pass a two-column matrix or sf object instead;
• Slot types in mpg, goc, grain, and corridor S4 classes have changed from RasterLayer/SpatialPoints/SpatialLines/SpatialLinesDataFrame to SpatRaster/sf;
• The long-deprecated gs-prefixed functions (gsMPG(), gsGOC(), gsGOCCorridor(), gsGOCDistance(), gsGOCPoint(), gsGOCVisualize(), gsGraphDataFrame(), gsMPGstitch()) are now defunct and error with a pointer to their replacement (deprecated since 0.4.0; #10);

New features

• New exported plotting helpers plotResistance() and plotWithResistance(): draw a resistance surface with a consistent colour scheme (and a discrete-value legend), and place it as an equally-sized reference panel beside a network plot for visual comparison. Both are demonstrated in the vignette's introductory figures (plotWithResistance() uses cowplot).

Bugfixes

• Fixed incorrect least-cost paths in MPG (#72);
• Fixed a regression in the #72 work where legitimate, non-redundant MPG links were dropped on high-variance resistance surfaces: the indirect-path search could treat an unset cell id (the internal -99 sentinel) as a pivot patch, fabricating a bogus two-hop route that suppressed a valid direct link. Such malformed links are now rejected and non-patch pivots are ignored (#72);
• Fixed patches being left isolated in the MPG: a patch cell that was never added as an active cell during spreading (e.g. a single-cell patch) kept the internal -99 id, so it was an unresolved link endpoint and all of its links were silently dropped. Every cell's id is now seeded from the voronoi map at initialization, so such patches are linked correctly (#72);
• Fixed an infinite loop (hang) in MPG(): a resistance surface whose first cell is NA left the C++ engine's internal cost range as NaN, so every patch cell was assigned a NaN resistance and never "settled", spinning forever. The engine now derives the cost range while skipping NA cells, and fully initializes its spreading-state struct, hardening it against this class of hang (#72);
• Fixed a Voronoi tessellation bias on high-variance resistance surfaces: patch (source) cells now begin spreading at the uniform minimum cost rather than the resistance of the cell they happen to overlap. Previously a patch sitting on a high-resistance cell spread late and lost territory to its neighbours, distorting the tessellation (and, in the extreme, leaving a patch with a single-cell region and no links). The fix changes only the tessellation: link weights are accumulated from the entered cells' resistances (independent of the source cell), so on the package's test surfaces the MPG and its weights are unchanged, and still match independent least-cost paths exactly (#72);
• Fixed graphdf returning a transposed (single-column) data frame for MPGs with only one link;
• patchFilter() no longer errors on R < 4.6 (with recent terra): it masked small patches via out[out %in% rmpatch] <- NA, which relies on %in% dispatching for a SpatRaster and fails with "'match' requires vector arguments" under older R; it now uses terra::subst() (#76);
• point() (and distance(), which calls it) now emit the "coords correspond to NA cells" warning once per call instead of once per coordinate-threshold combination (#50);
• The corridor plot() method now uses the linewidth aesthetic (rather than the deprecated size aesthetic) for its link segments, silencing a ggplot2 (>= 3.4.0) deprecation warning;

Vignette

• The "Calculating the minimum planar graph" vignette now generates its UML class diagrams, the algorithm flow chart, and the Engine call graphs directly from Graphviz/DiagrammeR specifications (rendered to vector PDFs with DiagrammeRsvg and rsvg) rather than embedding static images, so they stay in sync with the C++ engine; its technical reference was also updated for the #72 least-cost-path changes (the settled_map, createLinks(), and the parentResistance field) (#75);
• Corrected the thresholded-MPG figure (Figure 6), which plotted links above the dispersal threshold instead of the retained links below it (so the cheap, low-resistance links between neighbouring patches were hidden);
• Made the Euclidean-vs-resistance path-distance table robust by matching rows on the node pair (rather than column-binding two independently sorted tables), and the "patch 7 neighbours" table now filters explicitly for patch 7. The minimum-planar-graph figure above that table now labels exactly node 7 and its linked neighbours, derived from the graph rather than a hard-coded list of patch ids.

grainscape 0.5.0 (2025-01-15)

Dependency changes

• none

Bugfixes

• none

New features & enhancements

• none

Dependency changes

• Require R 4.2 or higher (for native pipe and placeholder)
• Add DiagrammeR, dplyr, webshot2 and withr to Suggests for use with vignettes and tests

Bugfixes

• Fixed documentation issues and 'memory not mapped' segfault errors on R-devel (#73)
• Improved handling of user-added attributes in exported objects (#71)
• Fixed partial match warnings
• Use replacements for deprecated igraph functions

New features & enhancements

• Use native R pipe throughout instead of magrittr pipe
• Improved documentation

grainscape 0.4.4 (2023-04-20)

Dependency changes

• Removed retiring spatial packages rgdal and rgeos (#68);
• Use sf for writing shapefiles;

Bugfixes

• Improved plotting of lattice MPGs (#51);
• Removed unused eucPerimWeight from documentation (#56);
• Improved error messaging for undefined thresholds in GOC() (#57);

New features & enhancements

• none

grainscape 0.4.3 (2020-09-01)

Dependency changes

• none

Bugfixes

• none

New features & enhancements

• added MEE paper citation and updated package DESCRIPTION & README.

grainscape 0.4.2 (2019-12-06)

Dependency changes

• removed unused dependency hunspell from Suggests

Bugfixes

• reduced package tarball size

New features & enhancements

• none

grainscape 0.4.1

Dependency changes

• none

Bugfixes

• fix error on R-devel exposed by change to matrix class
• fixed error in theme_grainscape() example

New features & enhancements

• added package hexsticker

grainscape 0.4.0 (2019-08-09)

Dependency changes

• Requires R >= 3.5
• remove rgeos dependency and deprecate use of sp argument to many functions (#38)

Bugfixes

• numerous bug fixes

New features & enhancements

• reimplement an algorithm to calculate the minimum planar graph using C++; no longer relies on SELES binary and is now cross-platform.
• use updated igraph functions internally
• updated vignette / tutorial (#5)
• renamed functions to remove gs and gsGOC prefixes; old names have been deprecated and will be removed in a future release (#10)
• MPG() can now handle large rasters
• use S4 classes and methods (#3, #19)
• improved plotting using ggplot2 by default (#22, #47)
• new functions export() (#39) and patchFilter() (#40)
• fix typos (#58, @jsta)

Removed features

• removed gsMPGstitch() as it was unreliable

grainscape 0.3.0

• original version from R-forge (http://grainscape.r-forge.r-project.org/)
• uses a SELES binary to calculate the minimum planar graph (Windows only)