@wandelbots/wandelbots-js-react-components/src/components/robots/robotModelLogic.ts

React UI toolkit for building applications on top of the Wandelbots platform

import type { Object3D } from "three"
import type { GLTF } from "three-stdlib"
import { version } from "../../../package.json"

export function defaultGetModel(modelFromController: string): string {
  let useVersion = version
  if (version.startsWith("0.")) {
    useVersion = ""
  }
  return `https://cdn.jsdelivr.net/gh/wandelbotsgmbh/wandelbots-js-react-components${useVersion ? `@${useVersion}` : ""}/public/models/${modelFromController}.glb`
}

/**
 * Finds all the joint groups in a GLTF tree, as identified
 * by the _Jxx name ending convention.
 */
export function collectJoints(rootObject: Object3D): Object3D[] {
  function getAllObjects(root: Object3D): Object3D[] {
    if (root.children.length === 0) {
      return [root]
    }
    return [root, ...root.children.flatMap((child) => getAllObjects(child))]
  }

  return getAllObjects(rootObject).filter((o) => isJoint(o))
}

/**
 * Checks if a specified threejs object represents the flange of a
 * robot, based on the _FLG name ending convention.
 */
export function isFlange(node: Object3D) {
  return node.name.endsWith("_FLG")
}

/**
 * Checks if a specified threejs object represents a joint of a
 * robot, based on the _Jxx name ending convention.
 */
export function isJoint(node: Object3D) {
  return /_J[0-9]+$/.test(node.name)
}

/**
 * Validates that the loaded GLTF file has six joints and a flange group.
 */
export function parseRobotModel(gltf: GLTF, filename: string): { gltf: GLTF } {
  let flange: Object3D | undefined
  const joints: Object3D[] = []

  function parseNode(node: Object3D) {
    if (isFlange(node)) {
      if (flange) {
        throw Error(
          `Found multiple flange groups in robot model ${filename}; first ${flange.name} then ${node.name}. Only one _FLG group is allowed.`,
        )
      }

      flange = node
    }

    if (isJoint(node)) {
      joints.push(node)
    }

    node.children.map(parseNode)
  }

  parseNode(gltf.scene)

  if (!flange) {
    throw Error(
      `No flange group found in robot model ${filename}. Flange must be identified with a name ending in _FLG.`,
    )
  }

  return { gltf }
}