micycle1 · micycle1 · Oct 4, 2025 · Feb 8, 2024 · Jan 19, 2025 · Jan 25, 2025
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -5,6 +5,79 @@ All notable changes to PGS will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). Dates are *YYYY-MM-DD*.
 
+## **2.1** *(2025-xx-xx)*
+
+### Added
+* `smoothLaneRiesenfeld` to `PGS_Morphology`. Smooths a shape using Lane-Riesenfeld curve subdivision with 4-point refinement to reduce contraction.
+* New method signature for `PGS_Conversion.roundVertexCoords()` that accepts a number of decimal places.
+* `interiorAngles()` to `PGS_ShapePredicates`. Calculates all interior angles of a polygon.
+* `forEachShape()` and `forEachShapeWithIndex()`* to `PGS_Processing`. Applies a specified transformation function of a desired type `T` to each child of the given PShape, returning a list of  `T` (*additionally with child's index).
+* `maximumInscribedTriangle()` to `PGS_Optimisation`. Finds an approximate largest area triangle (of arbitrary orientation) contained within a polygon.
+* `closestPoint()` to `PGS_Optimisation`. Finds the closest point in a collection of points to a specified point.
+* `distanceTree()` to `PGS_Contour`. Generates a tree structure representing the shortest paths from a start point to all other vertices in a mesh.
+* `vertexCount()` to `PGS_ShapePredicates`. Returns the total number of vertices that make up a shape.
+* `matchingQuadrangulation()` to `PGS_Meshing`. Converts a triangulation into a quadrangulation, by pairing up triangles and merging them into high-quality quads.
+* `filterNear()` to `PGS_SegmentSet`. Removes segments that are near others.
+* `spiralSortFaces()` to `PGS_Optimisation`. Reorders the faces of a mesh into an anti-clockwise “spiral” (breadth-first rings) starting from a given face.
+* `centroidSortFaces()` to `PGS_Optimisation`. Reorders the faces of a mesh by the x and then y coordinates of their centroids.
+* `radialSortFaces()` to `PGS_Optimisation`. Sorts the faces of a mesh radially around a given centre.
+* `unionLines()` to `PGS_ShapeBoolean`. Unions the linework of two shapes, creating polygonal faces from their intersecting lines.
+* `closestVertex()` and `farthestVertex()` to `PGS_Optimisation`. Returns the closest/farthest vertex of a shape to a query point.
+* `farthestPoint()` to `PGS_Optimsation`. Finds the farthest point in the collection from a specified point.
+* `annularBricks()` to `PGS_Tiling`. Generates a geometric arrangement composed of annular-sector bricks arranged in concentric circular rings.
+* `overlapRegions()` to `PGS_ShapeBoolean`. Finds the regions where at least two shapes overlap.
+* `normalise()` to `PGS_Processing`. Normalises a shape by standardising its vertex ordering and orientation.
+* `boundingBox()` to `PGS_Hull`. Calculates the axis-aligned bounding box (replaces `envelope()` in `PGS_Optimisation`.)
+* `farthestPointVoronoi()` to `PGS_Voronoi`. Generates a farthest-point Voronoi diagram for a given set of sites and a bounding box.
+* `intersections()` to `PGS_SegmentSet`. Computes all intersection points between two collections of line segments.
+* `minimumWidthAnnulus()` to `PGS_Optimisation`. Computes the minimum-width annulus (ring) that encloses the vertices of a shape.
+* Overloads of `minimumBoundingCircle()` and `maximumInscribedCircle()` that accept a PVector to output the circle center and radius.
+* `createRect()` to  `PGS_Construction`. Creates a rectangle with uniformly rounded corners
+* New method signature for `PGS_Meshing.areaMerge()` that allows merging faces until the mesh contains exactly a user-specified number of faces.
+* `minimumInteriorAngle()` to `PGS_ShapePredicates`. Computes the minimum interior angle of a shape.
+* New method signature for `isolines()` having an intervals parameter that specifies the number of contour levels to generate.
+* New method signature for `straightSkeleton()` that accepts an integer to control the number of nearest neighboring edges considered during collision detection.
+* `contrastField()` to `PGS_Contour`. Generates vector contour lines representing a "contrast field" of a shape with respect to a given reference point.
+* `arcDivision` to `PGS_Tiling`. Creates a cellular partition of the plane using arcs formed by circles seeded along its boundary.
+* `sliceDivision` to `PGS_Tiling`. Divides the plane into randomly “sliced” polygonal regions.
+* New method signature for `pointsOnExterior()` having a starting point offset parameter that specifies the distance along the perimeter to start sampling points.
+* `centroidSplit()` to `PGS_Processing`. Splits the input shape into n wedge-shaped regions by connecting the centroid to points along the perimeter.
+* `createHobbyCurve()` to `PGS_Construction`. Creates a Hobby curve from a set of control points.
+* `pruneRandomRemoveN()` to `PGS_PointSet`. Randomly removes exactly N points from a list of points.
+* `pruneRandomToN()` to `PGS_PointSet`. Randomly prunes a list of points to exactly N points.
+* `convexMaximumInscribedCircle()` to `PGS_Optimisation`. Computes the largest inscribed circle of a convex polygon (faster and exact).
+
+### Changes
+* Optimised `PGS_CirclePacking.tangencyPack()`. It's now around 1.5-2x faster and has higher precision.
+* `PGS_Conversion.roundVertexCoords()` now returns a rounded copy of the input (rather than mutating the input).
+* Outputs from `PGS_Conversion.toDualGraph()` will now always iterate deterministically on inputs with the same geometry but having a different structure.
+* `PGS_Contour.straightSkeleton()` now always uses a more robust approach (which has been sped up considerably too).
+* Optimised `ColoringAlgorithm.RLF` (the speed increase grows with input size).
+* Improved `PGS_PointSet.findShortestTour()` TSP algorithm. It now uses a more effective heuristic that finds shorter tours in less time.
+* `PGS_Meshing.extractInnerEdges()` no longer dissolves edges in the output.
+* `PGS_Morphology.simplifyHobby()` is much faster, particularly on shapes with many vertices.
+* Optimised `PGS_Processing.maximumPerimeterSquare()`. It's about 2x faster.
+* Varying `sigma` in `PGS_smoothGaussian()` no longer causes "wobblyness" in the output.
+* New method signature for `PGS_Morphology.buffer()` that accepts a cap style parameter.
+* `PGS_PointSet.squareGrid()` now populates the grid with points upto and including `xMax` and `yMax` (inclusive).
+* Improved `PGS_Transformation.touchScale()` algorithm. It's now more performant and robust.
+* `PGS_Tiling.triangleSubdivision()` can now begin from both diagonal axes, not just the top-left to bottom-right diagonal.
+* `PGS_Processing.pointsOnExterior()` methods now return points on all elements of a shape, not just the perimeter of the first polygon.
+* `PGS_Processing.segmentsOnExterior()` now return segments on all elements of a shape, not just the perimeter of the first polygon.
+* These methods in `PGS_Morphology` now process any and all polygon/line elements in a shape: `chaikinCut()`, `smoothGaussian()`, `simplifyDCE()`, `simplifyHobby()`, `smoothEllipticFourier()`, `round()`.
+* `dissolve()` to `PGS_Processing`. Dissolves the linear components of a shape into a set of unique maximal-length lines
+
+### Fixed
+* `PGS_Morphology.rounding()` no longer gives invalid results.
+* `PGS_ShapePredicates.elongation()` now correctly measures shape elongation (previously inverted, now returns 1 for highly elongated shapes).
+* `PGS_Conversion.toGraph()` now processes `LINES` shapes correctly.
+* `PGS_Meshing.urquhartFaces()` no longer errors on triangulation inputs with no constraints.
+* `PGS_Tiling.triangleSubdivision()` subdivision is now deterministic across `maxDepth` for a given seed.
+* `PGS_Tiling.rectSubdivision()` subdivision is now deterministic across `maxDepth` for a given seed.
+* `PGS_Morphology.pinchWarp()` now preserves closed polygon inputs.
+
+### Removed
+
 ## **2.0** *(2025-01-11)*
 
 **NOTE: Beginning at v2.0, PGS is built with Java 17.**

diff --git a/README.md b/README.md
@@ -21,7 +21,7 @@ Library functionality is split over the following classes:
 * `PGS_Contour`
   * Methods that produce various contours from shapes: medial axes, straight skeletons, offset curves, etc.
 * `PGS_Conversion`
-  * Conversion between *Processing* PShapes and *JTS* Geometries (amongst other formats)
+  * Conversion between *Processing* PShapes and *JTS* Geometries (amongst other formats).
 * `PGS_Hull`
   * Convex and concave hulls of polygons and point sets.
 * `PGS_Meshing`
@@ -74,6 +74,10 @@ PGS is hosted as an artifact for use in Maven or Gradle projects via [Jitpack](h
 A number of example Processing sketches are provided in [examples](https://github.com/micycle1/PGS/tree/master/examples).
 
 <p float="middle">
+  <a href="examples/organicSponge"><img src="resources/examples/organicSponge.png" alt="" width="24%"/></a>
+  <a href="examples/interlock"><img src="resources/examples/interlock.png" alt="" width="24%"/></a>
+  <a href="examples/warpedQuilt"><img src="resources/examples/warpedQuilt.png" alt="" width="24%"/></a>
+  <a href="examples/blobbies"><img src="resources/examples/blobbies.png" alt="" width="24%"/></a>
   <a href="examples/partitionSmooth"><img src="resources/examples/partitionSmooth.png" alt="" width="24%"/></a>
   <a href="examples/textOffsetCurves"><img src="resources/examples/textOffsetCurves.png" alt="" width="24%"/></a>
   <a href="examples/ripplingTriangles"><img src="resources/examples/ripplingTriangles.png" alt="" width="24%"/></a>
@@ -112,6 +116,15 @@ Much of the functionality (but by no means all) is demonstrated below:
     <td valign="top" width="25%"><img src="resources/boolean/intersectMesh.gif"></td>
     <td valign="top" width="25%"><img src="resources/boolean/subtractMesh.gif"></td>
   </tr>
+
+  <tr>
+    <td align="center" valign="center"><b>Union Lines</td>
+    <td align="center" valign="center"><b>Overlap Regions</td>
+  </tr>
+  <tr>
+    <td valign="top" width="25%"><img src="resources/boolean/unionLines.gif"></td>
+    <td valign="top" width="25%"><img src="resources/boolean/overlapRegions.gif"></td>
+  </tr>
 </table>
 
 ## *Transformation*
@@ -172,23 +185,15 @@ Much of the functionality (but by no means all) is demonstrated below:
 
 
 ### Metrics
-* Length/perimeter
-* Width & Height
-* Diameter
-* Circularity
-* Similarity
-* Sphericity
-* Elongation
-* Density
-* Holes
-* Maximum interior angle
-* Is simple?
-* Is convex?
-* Equal? (structural and topological equivalence)
-* Distance
-* Area
-* Centroid
-* Median
+
+| <!-- -->    | <!-- -->    | <!-- -->    |
+|-------------|-------------|-------------|
+| Length/perimeter | Similarity | Is simple? |
+| Width & Height | Sphericity | Is convex? |
+| Diameter | Elongation | Equal? (structural and topological equivalence) |
+| Circularity | Density | Distance |
+| Area | Holes | Centroid |
+| Interior angles | Maximum interior angle | Median |
 
 ## *Contour*
 
@@ -228,10 +233,14 @@ Much of the functionality (but by no means all) is demonstrated below:
   <tr>
     <td align="center" valign="center"><b>Distance Field</td>
     <td align="center" valign="center"><b>Center Line</td>
+    <td align="center" valign="center"><b>Distance Tree</td>
+    <td align="center" valign="center"><b>Contrast Field</td>
   </tr>
   <tr>
     <td valign="top"><img src="resources/contour/distanceField.png"></td>
     <td valign="top"><img src="resources/contour/centerLine.gif"></td>
+    <td valign="top"><img src="resources/contour/distanceTree.png"></td>
+    <td valign="top"><img src="resources/contour/contrastField.png"></td>
   </tr>
     </tr>
     <tr>
@@ -266,7 +275,7 @@ Much of the functionality (but by no means all) is demonstrated below:
   </tr>
   <tr>
     <td valign="top"><img src="resources/morphology/smooth.gif"></td>
-    <td valign="top"><img src="resources/morphology/gaussianSmooth.gif"></td>
+    <td valign="top"><img src="resources/morphology/smoothGaussian.gif"></td>
     <td valign="top"><img src="resources/morphology/round.gif"></td>
     <td valign="top" ><img src="resources/morphology/round2.gif"></td>
   </tr>
@@ -337,10 +346,12 @@ Much of the functionality (but by no means all) is demonstrated below:
   <tr>
     <td align="center" valign="center"><b>Convex Hull</td>
     <td align="center" valign="center"><b>Snap Hull</td>
+    <td align="center" valign="center"><b>Bounding Box</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/morphology/convexHull.png"></td>
     <td valign="top" width="25%"><img src="resources/morphology/snapHull.gif"></td>
+    <td valign="top" width="25%"><img src="resources/optimisation/envelope.png"></td>
   </tr>
   <tr>
     <td align="center" valign="center"></td>
@@ -437,11 +448,12 @@ Much of the functionality (but by no means all) is demonstrated below:
     <tr>
     <td align="center" valign="center"><b>Extract Holes</td>
     <td align="center" valign="center"><b>Nest</td>
-
+    <td align="center" valign="center"><b>Centroid Split</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/geometry_processing/extractHoles.gif"></td>
     <td valign="top" width="25%"><img src="resources/geometry_processing/nest.gif"></td>
+    <td valign="top" width="25%"><img src="resources/geometry_processing/centroidSplit.gif"></td>
   </tr>
 </table>
 
@@ -487,10 +499,12 @@ Much of the functionality (but by no means all) is demonstrated below:
   <tr>
     <td align="center" valign="center"><b>Centroidal Relaxation</td>
     <td align="center" valign="center"><b>Multiplicatively Weighted Voronoi</td>
+    <td align="center" valign="center"><b>Farthest-Point Voronoi</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/voronoi/centroidal.gif"></td>
     <td valign="top" width="25%"><img src="resources/voronoi/mwvd.gif"></td>
+    <td valign="top" width="25%"><img src="resources/voronoi/fpvd.gif"></td>
   </tr>
 </table>
 
@@ -553,10 +567,12 @@ Much of the functionality (but by no means all) is demonstrated below:
   <tr>
     <td align="center" valign="center"><b>Extract Inner Vertices</td>
     <td align="center" valign="center"><b>Fix Breaks</td>
+    <td align="center" valign="center"><b>Matching Quadrangulation</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/meshing/extractInnerVertices.gif"></td>
     <td valign="top" width="25%"><img src="resources/geometry_processing/cleanCoverage.gif"></td>
+    <td valign="top" width="25%"><img src="resources/meshing/matchingQuadrangulation.png"></td>
   </tr>
 </table>
 
@@ -577,24 +593,25 @@ Much of the functionality (but by no means all) is demonstrated below:
   </tr>
 
   <tr>
-    <td align="center" valign="center" colspan="2"><b>Minimum Bounding Circle</td>
+    <td align="center" valign="center"><b>Maximum Inscribed Triangle</td>
+    <td align="center" valign="center"><b>Minimum Bounding Circle</td>
     <td align="center" valign="center" colspan="2"><b>Minimum Bounding Ellipse</td>
   </tr>
   <tr>
+    <td valign="top"><img src="resources/optimisation/mit.png"></td>
     <td valign="top"><img src="resources/optimisation/minimumBoundingCircle.png"></td>
-    <td valign="top"><img src="resources/optimisation/mbc2.png"></td>
     <td valign="top"><img src="resources/optimisation/mbe1.png"></td>
     <td valign="top" ><img src="resources/optimisation/mbe2.png"></td>
   </tr>
 
   <tr>
     <td align="center" valign="center"><b>Minimum Bounding Triangle</td>
-    <td align="center" valign="center"><b>Envelope</td>
+    <td align="center" valign="center"><b>Minimum-width Annulus</td>
     <td align="center" valign="center" colspan="2"><b>Problem of Apollonius</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/optimisation/mbt.png"></td>
-    <td valign="top" width="25%"><img src="resources/optimisation/envelope.png"></td>
+    <td valign="top" width="25%"><img src="resources/optimisation/minWidthAnnulus.png"></td>
     <td valign="top"><img src="resources/optimisation/apollonius1.gif"></td>
     <td valign="top"><img src="resources/optimisation/apollonius2.gif"></td>
   </tr>
@@ -613,13 +630,13 @@ Much of the functionality (but by no means all) is demonstrated below:
   </tr>
 
   <tr>
-    <td align="center" valign="center"><b>Closest Vertex</td>
     <td align="center" valign="center"><b>Circle Covering</td>
+    <td align="center" valign="center"><b>Closest Vertex</td>
     <td align="center" valign="center" colspan="2"><b>Visibility Polygon / Isovist</td>
   </tr>
   <tr>
-    <td valign="top" width="25%"><img src="resources/pgs/closestVertex.gif"></td>
     <td valign="top" width="25%"><img src="resources/optimisation/circleCoverage.gif"></td>
+    <td valign="top" width="25%"><img src="resources/pgs/closestVertex.gif"></td>
     <td valign="top" width="25%"><img src="resources/optimisation/visibility.gif"></td>
     <td valign="top" width="25%"><img src="resources/optimisation/visibility2.gif"></td>
   </tr>
@@ -637,9 +654,13 @@ Much of the functionality (but by no means all) is demonstrated below:
 
   <tr>
     <td align="center" valign="center"><b>Hilbert Sort Faces</td>
+    <td align="center" valign="center"><b>Spiral Sort Faces</td>
+    <td align="center" valign="center"><b>Centroid Sort Faces</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/optimisation/hilbertSortFaces.gif"></td>
+    <td valign="top" width="25%"><img src="resources/optimisation/spiralSort.gif"></td>
+    <td valign="top" width="25%"><img src="resources/optimisation/centroidSort.gif"></td>
   </tr>
 
 </table>
@@ -925,9 +946,19 @@ Much of the functionality (but by no means all) is demonstrated below:
   <tr>
     <td align="center" valign="center"><b>Penrose Tiling</td>
     <td align="center" valign="center"><b>Square-Triangle Tiling</td>
+    <td align="center" valign="center"><b>Annular Bricks</td>
+    <td align="center" valign="center"><b>Slice Division</td>
   </tr>
   <tr>
     <td valign="top" width="25%"><img src="resources/tiling/penrose.png"></td>
     <td valign="top" width="25%"><img src="resources/tiling/stTiling.png"></td>
+    <td valign="top" width="25%"><img src="resources/tiling/annularBricks.png"></td>
+    <td valign="top" width="25%"><img src="resources/tiling/sliceDivision.png"></td>
+  </tr>
+  <tr>
+    <td align="center" valign="center"><b>Arc Division</td>
+  </tr>
+  <tr>
+    <td valign="top" width="25%"><img src="resources/tiling/arcDivision.png"></td>
   </tr>
 </table>
diff --git a/examples/README.md b/examples/README.md
@@ -4,6 +4,10 @@ A collection of example Processing sketches using *Processing Geometry Suite*. T
 
 All examples are dynamic and/or interactive. Shown below are merely screenshots.
 
+## blobbies
+
+<img src="../resources/examples/blobbies.png" alt="" width="500"/>
+
 ## blowUp
 
 <img src="../resources/examples/blowUp.png" alt="" width="500"/>
@@ -20,6 +24,10 @@ All examples are dynamic and/or interactive. Shown below are merely screenshots.
 
 <img src="../resources/examples/dysonHatching.png" alt="" width="500"/>
 
+## interlock
+
+<img src="../resources/examples/interlock.png" alt="" width="500"/>
+
 ## intersectionBoids
 
 <img src="../resources/examples/intersectionBoids.png" alt="" width="500"/>
@@ -52,6 +60,10 @@ All examples are dynamic and/or interactive. Shown below are merely screenshots.
 
 <img src="../resources/examples/ripplingTriangles.png" alt="" width="500"/>
 
+## organicSponge
+
+<img src="../resources/examples/organicSponge.png" alt="" width="500"/>
+
 ## slice
 
 <img src="../resources/examples/slice.png" alt="" width="500"/>
@@ -78,4 +90,8 @@ All examples are dynamic and/or interactive. Shown below are merely screenshots.
 
 ## voronoiCutout
 
-<img src="../resources/examples/voronoiCutout.png" alt="" width="500"/>
+<img src="../resources/examples/voronoiCutout.png" alt="" width="500"/>
+
+## warpedQuilt
+
+<img src="../resources/examples/warpedQuilt.png" alt="" width="500"/>