@bitbybit-dev/manifold/lib/api/manifold-service.js

Bit By Bit Developers Manifold based CAD Library to Program Geometry

import { Manifold } from "./services/manifold/manifold";
import { CrossSection } from "./services/cross-section/cross-section";
import { Mesh } from "./services/mesh/mesh";
import { BaseBitByBit } from "../base";
// Worker make an instance of this class itself
export class ManifoldService {
    constructor(wasm) {
        this.base = new BaseBitByBit();
        this.crossSection = new CrossSection(wasm, this.base);
        this.manifold = new Manifold(wasm);
        this.mesh = new Mesh(wasm);
    }
    toPolygonPoints(inputs) {
        // Ensure the manifold is decomposed to access the mesh data.
        // The getMesh() method provides the necessary structure.
        if (inputs.manifold.getMesh) {
            const mesh = inputs.manifold.getMesh();
            if (!mesh || !mesh.vertProperties || !mesh.triVerts || mesh.vertProperties.length === 0 || mesh.triVerts.length === 0) {
                console.warn("Manifold does not contain valid mesh data or is empty.");
                return [];
            }
            const vertProperties = mesh.vertProperties; // Float32Array [x1, y1, z1, [prop4...], x2, y2, z2, [prop4...]...]
            const triVerts = mesh.triVerts; // Uint32Array [idx1, idx2, idx3, idx4, idx5, idx6, ...]
            const numProp = mesh.numProp; // Number of properties per vertex
            // We need at least x, y, z data.
            if (numProp < 3) {
                throw new Error(`Cannot convert to PolygonPoints: Expected numProp >= 3 (for x, y, z), but found ${numProp}.`);
            }
            if (triVerts.length % 3 !== 0) {
                throw new Error(`Mesh data corruption: triVerts length (${triVerts.length}) is not a multiple of 3.`);
            }
            const polygons = [];
            const numVertices = vertProperties.length / numProp;
            for (let i = 0; i < triVerts.length; i += 3) {
                const index1 = triVerts[i];
                const index2 = triVerts[i + 1];
                const index3 = triVerts[i + 2];
                if (index1 >= numVertices || index2 >= numVertices || index3 >= numVertices) {
                    console.error(`Invalid vertex index found in triVerts at offset ${i}. Max index should be ${numVertices - 1}. Indices: ${index1}, ${index2}, ${index3}`);
                    continue; // Skip this triangle
                }
                // Calculate the starting position of each vertex's data in vertProperties.
                // This calculation works regardless of numProp.
                const vert1Offset = index1 * numProp;
                const vert2Offset = index2 * numProp;
                const vert3Offset = index3 * numProp;
                // Extract only the first 3 properties (x, y, z) starting from the offset for each vertex.
                const point1 = [vertProperties[vert1Offset], vertProperties[vert1Offset + 1], vertProperties[vert1Offset + 2]];
                const point2 = [vertProperties[vert2Offset], vertProperties[vert2Offset + 1], vertProperties[vert2Offset + 2]];
                const point3 = [vertProperties[vert3Offset], vertProperties[vert3Offset + 1], vertProperties[vert3Offset + 2]];
                const triangle = [point1, point2, point3];
                polygons.push(triangle);
            }
            return polygons;
        }
        else {
            return undefined;
        }
    }
    decomposeManifoldOrCrossSection(inputs) {
        if (inputs.manifoldOrCrossSection.getMesh) {
            return inputs.manifoldOrCrossSection.getMesh(inputs.normalIdx);
        }
        else {
            return inputs.manifoldOrCrossSection.toPolygons();
        }
    }
    decomposeManifoldsOrCrossSections(inputs) {
        return inputs.manifoldsOrCrossSections.map((manifoldOrCrossSection, index) => {
            const normalIdx = inputs.normalIdx ? inputs.normalIdx[index] : undefined;
            return this.decomposeManifoldOrCrossSection({
                manifoldOrCrossSection,
                normalIdx
            });
        });
    }
}