STL Loading

/**
 * STL file loader supporting both ASCII and binary STL formats
 */
class STLFileLoader implements ISceneLoaderPlugin {
  /** Don't alter file coordinates during import (default: false) */
  static DO_NOT_ALTER_FILE_COORDINATES: boolean;
  
  // Core properties  
  readonly name: string; // "stl"
  readonly extensions: { [key: string]: { isBinary: boolean } }; // { ".stl": { isBinary: true } }
  
  // Parsing regex patterns
  readonly solidPattern: RegExp;
  readonly facetsPattern: RegExp; 
  readonly normalPattern: RegExp;
  readonly vertexPattern: RegExp;
  
  /**
   * Import mesh from STL file data
   * @param meshesNames - Names of meshes to import (ignored for STL)
   * @param scene - Target scene for the mesh
   * @param data - STL file data as string or ArrayBuffer
   * @param rootUrl - Root URL for the file (used for naming)
   * @param meshes - Array to receive the imported meshes
   * @param onProgress - Progress callback
   * @param fileName - Name of the STL file
   * @returns True if import succeeded
   */
  importMesh(
    meshesNames: any,
    scene: Scene,
    data: string | ArrayBuffer,
    rootUrl: string,
    meshes: AbstractMesh[],
    onProgress?: (event: ISceneLoaderProgressEvent) => void,
    fileName?: string
  ): boolean;
  
  /**
   * Load STL file into an asset container
   * @param scene - Target scene
   * @param data - STL file data
   * @param rootUrl - Root URL for the file
   * @param onProgress - Progress callback  
   * @param fileName - Name of the STL file
   * @returns Asset container with the loaded mesh
   */
  loadAssetContainer(
    scene: Scene,
    data: string | ArrayBuffer,
    rootUrl: string,
    onProgress?: (event: ISceneLoaderProgressEvent) => void,
    fileName?: string
  ): AssetContainer;
}

import { STLFileLoader } from "@babylonjs/loaders";
import { SceneLoader } from "@babylonjs/core";

// Basic usage with automatic loader selection
const result = await SceneLoader.ImportMeshAsync("", "/models/", "part.stl", scene);
const mesh = result.meshes[0];

console.log(`Loaded STL mesh: ${mesh.name}`);
console.log(`Vertices: ${mesh.getTotalVertices()}`);

// Configure coordinate system handling
STLFileLoader.DO_NOT_ALTER_FILE_COORDINATES = true;

// Load with coordinate preservation
const result2 = await SceneLoader.ImportMeshAsync("", "/cad/", "precise_part.stl", scene);

import { STLFileLoader } from "@babylonjs/loaders";

const loader = new STLFileLoader();

// Load STL data (from file or fetch)
const stlData = await fetch("/models/gear.stl").then(r => r.arrayBuffer());

// Load into asset container
const assetContainer = loader.loadAssetContainer(scene, stlData, "/models/", undefined, "gear.stl");

console.log(`Loaded ${assetContainer.meshes.length} meshes`);

// The mesh is loaded but not added to scene automatically
// Add when ready
assetContainer.addAllToScene();

// Or access the mesh directly
const stlMesh = assetContainer.meshes[0];
stlMesh.position.x = 5;

solid name
  facet normal nx ny nz
    outer loop
      vertex x1 y1 z1
      vertex x2 y2 z2
      vertex x3 y3 z3
    endloop
  endfacet
  ...
endsolid name

import { STLFileLoader } from "@babylonjs/loaders";

// Preserve original coordinate system (useful for CAD precision)
STLFileLoader.DO_NOT_ALTER_FILE_COORDINATES = true;

// Default behavior applies Babylon.js coordinate system transformations
STLFileLoader.DO_NOT_ALTER_FILE_COORDINATES = false;

import { STLFileLoader, StandardMaterial, Color3 } from "@babylonjs/loaders";

// Load STL mesh
const result = await SceneLoader.ImportMeshAsync("", "/models/", "part.stl", scene);
const mesh = result.meshes[0];

// STL meshes have no material by default - create one
const material = new StandardMaterial("stlMaterial", scene);
material.diffuseColor = new Color3(0.8, 0.8, 0.8);
material.specularColor = new Color3(0.2, 0.2, 0.2);

mesh.material = material;

// Enable wireframe view (common for STL inspection)
material.wireframe = true;

import { STLFileLoader } from "@babylonjs/loaders";

// For large STL files, consider mesh optimization
const result = await SceneLoader.ImportMeshAsync("", "/models/", "large_part.stl", scene);
const mesh = result.meshes[0];

// Optimize mesh for rendering
mesh.simplify([
  { quality: 0.8, distance: 0.1 }
], false, () => {
  console.log("Mesh simplified");
});

// Or freeze mesh if it won't change
mesh.freezeWorldMatrix();
mesh.material?.freeze();

import "@babylonjs/loaders/STL";
import { SceneLoader, StandardMaterial, Color3 } from "@babylonjs/core";

// Load STL for 3D printing preview
const result = await SceneLoader.ImportMeshAsync("", "/prints/", "model.stl", scene);
const printMesh = result.meshes[0];

// Apply print material appearance
const printMaterial = new StandardMaterial("printMaterial", scene);
printMaterial.diffuseColor = new Color3(0.9, 0.9, 0.9);
printMaterial.specularColor = new Color3(0.1, 0.1, 0.1);
printMaterial.roughness = 0.8;

printMesh.material = printMaterial;

// Center the model
const boundingInfo = printMesh.getBoundingInfo();
const center = boundingInfo.boundingBox.center;
printMesh.position.subtractInPlace(center);

import { STLFileLoader } from "@babylonjs/loaders";

// Preserve exact coordinates for CAD precision
STLFileLoader.DO_NOT_ALTER_FILE_COORDINATES = true;

const result = await SceneLoader.ImportMeshAsync("", "/cad/", "precision_part.stl", scene);
const cadMesh = result.meshes[0];

// Inspect mesh properties
console.log(`Bounding box: ${cadMesh.getBoundingInfo().boundingBox.extendSize}`);
console.log(`Vertex count: ${cadMesh.getTotalVertices()}`);
console.log(`Face count: ${cadMesh.getTotalIndices() / 3}`);

// Enable wireframe for detailed inspection
const wireframeMaterial = new StandardMaterial("wireframe", scene);
wireframeMaterial.wireframe = true;
wireframeMaterial.diffuseColor = new Color3(0, 1, 0);
cadMesh.material = wireframeMaterial;