refactor: move the density clustering code to its own internal package (#33)

Author: donghaoren

.gitignore

@@ -6,7 +6,6 @@ build/
 dist/
 distlib/
 target/
-pkg/
 .svelte-kit/
 .env
 .env.*

package-lock.json

@@ -5,6 +5,7 @@
     "packages/viewer",
     "packages/table",
     "packages/umap-wasm",
+    "packages/density-clustering",
     "packages/embedding-atlas",
     "packages/examples",
     "packages/backend",

package.json

@@ -1,6 +1,6 @@
 // Copyright (c) 2025 Apple Inc. Licensed under MIT License.
 
-import { findClusters } from "../../density_clustering/find_clusters.js";
+import { findClusters } from "@embedding-atlas/density-clustering";
 import { dynamicLabelPlacement } from "../../dynamic_label_placement/dynamic_label_placement.js";
 
 export { dynamicLabelPlacement, findClusters };

packages/component/src/lib/density_clustering/wasm/density_clustering_wasm_bg.wasm

@@ -8,8 +8,6 @@ export {
   type EmbeddingViewProps,
 } from "./embedding_view/api.js";
 
-export { findClusters, type Cluster, type FindClustersOptions } from "./density_clustering/find_clusters.js";
-
 export { defaultCategoryColors } from "./colors.js";
 
 export type { Theme } from "./embedding_view/theme.js";

packages/component/src/lib/embedding_view/worker/worker_functions.ts

@@ -0,0 +1,42 @@
+/** A resulting cluster from the find clusters function */
+export interface Cluster {
+  /** Cluster identifier */
+  identifier: number;
+  /** The total density */
+  sum_density: number;
+  /** The mean x location (weighted by density) */
+  mean_x: number;
+  /** The mean y location (weighted by density) */
+  mean_y: number;
+  /** The maximum density */
+  max_density: number;
+  /** The location with the maximum density */
+  max_density_location: [number, number];
+  /** The number of pixels in the cluster */
+  pixel_count: number;
+  /** The cluster's boundary represented as a list of polygons */
+  boundary?: [number, number][][];
+  /** The cluster's boundary approximated with a list of rectangles */
+  boundary_rect_approximation?: [number, number, number, number][];
+}
+
+/** Options of the find clusters function */
+export interface FindClustersOptions {
+  /** The threshold for unioning two clusters */
+  union_threshold: number;
+}
+
+/**
+ * Find clusters from a density map
+ * @param density_map the density map, a `Float32Array` with `width * height` elements
+ * @param width the width of the density map
+ * @param height the height of the density map
+ * @param options algorithm options
+ * @returns
+ */
+export async function findClusters(
+  density_map: Float32Array,
+  width: number,
+  height: number,
+  options: Partial<FindClustersOptions> = {},
+): Promise<Cluster[]>;

packages/component/src/lib/index.ts

@@ -1,34 +1,6 @@
 // Copyright (c) 2025 Apple Inc. Licensed under MIT License.
 
-import * as cluster from "./wasm/density_clustering_wasm.js";
-
-/** A resulting cluster from the find clusters function */
-export interface Cluster {
-  /** Cluster identifier */
-  identifier: number;
-  /** The total density */
-  sum_density: number;
-  /** The mean x location (weighted by density) */
-  mean_x: number;
-  /** The mean y location (weighted by density) */
-  mean_y: number;
-  /** The maximum density */
-  max_density: number;
-  /** The location with the maximum density */
-  max_density_location: [number, number];
-  /** The number of pixels in the cluster */
-  pixel_count: number;
-  /** The cluster's boundary represented as a list of polygons */
-  boundary?: [number, number][][];
-  /** The cluster's boundary approximated with a list of rectangles */
-  boundary_rect_approximation?: [number, number, number, number][];
-}
-
-/** Options of the find clusters function */
-export interface FindClustersOptions {
-  /** The threshold for unioning two clusters */
-  union_threshold: number;
-}
+import * as cluster from "../pkg/density_clustering_wasm.js";
 
 /**
  * Find clusters from a density map
@@ -38,12 +10,7 @@ export interface FindClustersOptions {
  * @param options algorithm options
  * @returns
  */
-export async function findClusters(
-  density_map: Float32Array,
-  width: number,
-  height: number,
-  options: Partial<FindClustersOptions> = {},
-): Promise<Cluster[]> {
+export async function findClusters(density_map, width, height, options = {}) {
   await cluster.default();
   // console.debug(`find clusters start, size: ${width}x${height}`);
   let t0 = new Date().getTime();
@@ -62,7 +29,7 @@ export async function findClusters(
     smooth_boundaries: true,
   });
   input.free();
-  let clusters: Cluster[] = [];
+  let clusters = [];
   for (let [id, summary] of result.summaries) {
     clusters.push({
       identifier: id,