bakana/browser/steps/utils/viz_child.js

Backend for kana's single-cell analyses. This supports single or multiple samples, execution in Node.js or the browser, in-memory caching of results for iterative analyses, and serialization to/from file for redistribution.

import * as scran from "scran.js";

export function chooseDelay(animate) {
    if (animate) {
        // TODO: using 75 for now
        // in the future the user can choose a bar for speed on the UI
        // options would be 1x, 2x, 3x
        return 75;
    } else {
        return 1000000; // effectively no delay.
    }
};

export function recreateNeighbors(neighbors) {
    var output = null;
    var rbuf = null;
    var ibuf = null;
    var dbuf = null;
  
    try {
        var num_obs = neighbors.num_obs;
        var size = neighbors.size;

        rbuf = scran.createInt32WasmArray(num_obs);
        rbuf.set(neighbors.runs);
        ibuf = scran.createInt32WasmArray(size);
        ibuf.set(neighbors.indices);
        dbuf = scran.createFloat64WasmArray(size);
        dbuf.set(neighbors.distances);

        output = scran.FindNearestNeighborsResults.unserialize(rbuf, ibuf, dbuf);

    } finally {
        if (rbuf !== null) {
            rbuf.free();
        }
        if (ibuf !== null) {
            ibuf.free();
        }
        if (dbuf !== null) {
            dbuf.free();
        }
    }

    return output;
};