This project is part of the @thi.ng/umbrella monorepo.
For the Clojure version, please visit: thi.ng/geom-clj
Functional, polymorphic API for 2D geometry types & SVG generation.
This project is a partially ported from the Clojure version of the same name. All polymorphic operations built on @thi.ng/defmulti.
The following operations are provided (many also applicable to shape groups directly and/or perform automatic resampling/conversion if needed):
| Operation | Description |
|---|---|
arcLength() |
compute arc length / perimeter of shape boundary |
area() |
signed/unsigned surface area |
asCubic() |
convert shape boundary to cubic bezier segments |
asPath() |
convert shape to path |
asPolygon() |
convert shape to polygon |
asPolyline() |
convert shape to polyline |
asSvg() |
serialize shape/group/hierarchy to SVG |
bounds() |
compute bounding box |
center() |
center shape around origin or point |
centroid() |
compute shape centroid |
classifyPoint() |
classify point in relation to shape boundary (in/out) |
clipConvex() |
clip shape against convex boundary |
closestPoint() |
compute closest point on shape boundary |
convexHull() |
compute convex hull (2d only) |
edges() |
extract edges |
fitIntoBounds() |
rescale/reposition shapes into a destination boundary |
flip() |
reverse order (vertices or direction) |
intersects() |
pairwise shape intersection (various types) |
mapPoint() |
transform world space point into local shape space |
offset() |
shape/path offsetting |
pointAt() |
compute point on shape boundary at parametric position |
pointInside() |
check if point is inside shape |
resample() |
resample/convert shape |
rotate() |
rotate shape |
scale() |
scale shape (uniformly/non-uniformly) |
scatter() |
create random points inside a shape boundary |
simplify() |
simplify shape/boundary (Douglas-Peucker) |
splitAt() |
split shape/boundary at parametric position |
splitNear() |
split shape/boundary near world position |
subdivCurve() |
recursively apply curve subdivision kernel |
tangentAt() |
compute tangent at parametric position |
tessellate() |
(recursively) tessellate shape |
transformVertices() |
apply custom function to each vertex |
transform() |
apply transformation matrix |
translate() |
translate shape |
union() |
compute shape union |
vertices() |
extract/sample vertices from shape boundary |
volume() |
compute shape volume (3D only) |
warpPoints() |
transfer points between the local spaces defined by 2 shapes |
This package acts as a higher-level frontend for most of the following related packages (which are more low-level, lightweight and usable by themselves too):
- @thi.ng/geom-accel - n-D spatial indexing data structures with a shared ES6 Map/Set-like API
- @thi.ng/geom-api - Shared type & interface declarations for @thi.ng/geom packages
- @thi.ng/geom-arc - 2D circular / elliptic arc operations
- @thi.ng/geom-clip-line - 2D line clipping (Liang-Barsky)
- @thi.ng/geom-clip-poly - 2D polygon clipping / offsetting (Sutherland-Hodgeman, Grainer-Hormann)
- @thi.ng/geom-closest-point - 2D / 3D closest point / proximity helpers
- @thi.ng/geom-fuzz - Highly configurable, fuzzy line & polygon creation with presets and composable fill & stroke styles. Canvas & SVG support
- @thi.ng/geom-hull - Fast 2D convex hull (Graham Scan)
- @thi.ng/geom-io-obj - Wavefront OBJ parser (& exporter soon)
- @thi.ng/geom-isec - 2D/3D shape intersection checks
- @thi.ng/geom-isoline - Fast 2D contour line extraction / generation
- @thi.ng/geom-poly-utils - 2D polygon/polyline analysis & processing utilities
- @thi.ng/geom-resample - Customizable nD polyline interpolation, re-sampling, splitting & nearest point computation
- @thi.ng/geom-sdf - 2D Signed Distance Field creation from @thi.ng/geom shapes, conversions, sampling, combinators
- @thi.ng/geom-splines - nD cubic & quadratic curve analysis, conversion, interpolation, splitting
- @thi.ng/geom-subdiv-curve - Freely customizable, iterative nD subdivision curves for open / closed geometries
- @thi.ng/geom-tessellate - 2D/3D convex polygon tessellators
- @thi.ng/geom-voronoi - Fast, incremental 2D Delaunay & Voronoi mesh implementation
STABLE - used in production
Search or submit any issues for this package
yarn add @thi.ng/geomES module import:
<script type="module" src="https://cdn.skypack.dev/@thi.ng/geom"></script>For Node.js REPL:
# with flag only for < v16
node --experimental-repl-await
> const geom = await import("@thi.ng/geom");
Package sizes (gzipped, pre-treeshake): ESM: 13.50 KB
- @thi.ng/api
- @thi.ng/arrays
- @thi.ng/associative
- @thi.ng/checks
- @thi.ng/defmulti
- @thi.ng/equiv
- @thi.ng/errors
- @thi.ng/geom-api
- @thi.ng/geom-arc
- @thi.ng/geom-clip-line
- @thi.ng/geom-clip-poly
- @thi.ng/geom-closest-point
- @thi.ng/geom-hull
- @thi.ng/geom-isec
- @thi.ng/geom-poly-utils
- @thi.ng/geom-resample
- @thi.ng/geom-splines
- @thi.ng/geom-subdiv-curve
- @thi.ng/geom-tessellate
- @thi.ng/hiccup
- @thi.ng/hiccup-svg
- @thi.ng/math
- @thi.ng/matrices
- @thi.ng/random
- @thi.ng/strings
- @thi.ng/transducers
- @thi.ng/vectors
Several demos in this repo's /examples directory are using this package.
A selection:
| Screenshot | Description | Live demo | Source |
|---|---|---|---|
 |
Convex hull & shape clipping of 2D polygons | Demo | Source |
 |
geom-fuzz basic shape & fill examples | Demo | Source |
 |
Animated, recursive polygon tessellations | Demo | Source |
 |
Poisson-disk shape-aware sampling, Voronoi & Minimum Spanning Tree visualization | Demo | Source |
 |
Mouse gesture / stroke analysis, simplification, corner detection | Demo | Source |
 |
2D Bezier curve-guided particle system | Demo | Source |
 |
Animated arcs & drawing using hiccup-canvas | Demo | Source |
 |
Canvas based Immediate Mode GUI components | Demo | Source |
 |
Animated sine plasma effect visualized using contour lines | Demo | Source |
 |
2D Poisson-disc sampler with procedural gradient map | Demo | Source |
 |
Polygon to cubic curve conversion & visualization | Demo | Source |
 |
Animated Voronoi diagram, cubic splines & SVG download | Demo | Source |
 |
2D scenegraph & shape picking | Demo | Source |
 |
2D scenegraph & image map based geometry manipulation | Demo | Source |
 |
Compute cubic spline position & tangent using Dual Numbers | Demo | Source |
 |
3D wireframe textmode demo | Demo | Source |
TODO
Karsten Schmidt
If this project contributes to an academic publication, please cite it as:
@misc{thing-geom,
title = "@thi.ng/geom",
author = "Karsten Schmidt",
note = "https://thi.ng/geom",
year = 2013
}© 2013 - 2022 Karsten Schmidt // Apache Software License 2.0