addBoundary             Add boundary outlines to a spatial ggplot
addBoundaryPoly         Add boundary polygons or linestrings to a
                        spatial plot
boundaryPolyToPoints    Convert boundary polygons to boundary point
                        coordinates
buildBoundaryPoly       Convert boundary points into valid polygon
                        geometries
colors15_cheng          Custom Color Palette
computeBoundaryWeights
                        Compute spatial weights based on distance to
                        nearest boundary
computeCentroidWeights
                        Compute spatial weights based on distance to
                        the centroid
computeSEI              Compute Spatial Enrichment Index (SEI)
computeSpatialEnrichmentIndex
                        Compute Spatial Enrichment Index (SEI) for Each
                        Gene
computeSpatialInteractionMatrix
                        Compute a spatial neighborhood interaction
                        matrix using K-nearest neighbors (KNN)
extractCoords           Extract spatial coordinates and cluster
                        information
factorNaturalOrder      Create a factor with natural (human-friendly)
                        ordering
getBoundary             Extract spatial boundary points for a cluster
                        or cell population
getCellsInside          Identify cells located within spatial
                        boundaries or ring regions
getInnerBoundary        Generate an inner boundary polygon by shrinking
                        an existing boundary inward
getOuterBoundary        Generate an outer or inner boundary polygon by
                        buffering an existing boundary
getRingRegion           Generate ring regions between a boundary and
                        its outer buffer
plotBoundary            Plot spatial cell coordinates with cluster
                        boundaries
plotCellsInside         Plot cells located within spatial boundaries or
                        ring regions
plotEdge                Plot boundary edges or segmented boundary lines
plotExpression          Plot gene expression across spatial coordinates
plotInteractionMatrix   Plot a heatmap of a row-scaled spatial
                        interaction matrix
plotRegion              Plot filled spatial regions inside boundaries
                        or rings
plotSpatialExpression   Plot average gene expression along spatial
                        distance
plotStatsBar            Bar plot of cluster statistics for cells inside
                        boundaries or ring regions
plotStatsPie            Pie chart or donut chart of cluster proportions
                        inside spatial regions
plotWeights             Plot spatial weights for cells on a spatial
                        plot
removeOutliers          Removes spatial outlier cells based on local
                        k-nearest neighbor distances
runLimmaDE              Differential expression analysis between two
                        groups of cells using limma
runSpatialDE            Differential expression along spatial distance
                        gradients using splines
safeColorPalette        Generate a safe color palette for discrete
                        clusters
splineDesign            Generate an orthonormal spline-based design
                        matrix
splitBoundaryPolyByAnchor
                        Split a polygon boundary into two parts using
                        anchor points
statsCellsInside        Summarize cell counts and proportions inside
                        spatial regions
theme_spneigh           Custom ggplot2 theme
