the-nexus/modules/portals.js

// === PORTALS ===
import * as THREE from 'three';
import { scene } from './scene-setup.js';
import { rebuildRuneRing, setPortalsRef } from './effects.js';
import { setPortalsRefAudio, startPortalHums } from './audio.js';
import { S } from './state.js';

export const portalGroup = new THREE.Group();
scene.add(portalGroup);

export let portals = [];

// Shared geometry and material for all portal tori — populated in createPortals()
const _portalGeo = new THREE.TorusGeometry(3.0, 0.2, 16, 100);
const _portalMat = new THREE.MeshBasicMaterial({
  color: 0xffffff,  // instance color provides per-portal tint
  transparent: true,
  opacity: 1.0,     // online/offline brightness encoded into instance color
  blending: THREE.AdditiveBlending,
  side: THREE.DoubleSide,
  depthWrite: false,
});
const _portalDummy = new THREE.Object3D();
const _portalColor = new THREE.Color();

/** @type {THREE.InstancedMesh|null} */
let _portalIM = null;

function createPortals() {
  // One InstancedMesh for all portal tori — N portals = 1 draw call.
  _portalIM = new THREE.InstancedMesh(_portalGeo, _portalMat, portals.length);
  _portalIM.instanceMatrix.setUsage(THREE.DynamicDrawUsage);
  _portalIM.userData.zoomLabel = 'Portal';
  _portalIM.userData.portals = portals; // for instanceId look-up on click

  portals.forEach((portal, i) => {
    const isOnline = portal.status === 'online';
    // Encode online/offline brightness into the instance color so we need
    // only one shared material (AdditiveBlending: output = bg + color).
    _portalColor.set(portal.color).convertSRGBToLinear()
      .multiplyScalar(isOnline ? 0.7 : 0.15);
    _portalIM.setColorAt(i, _portalColor);

    _portalDummy.position.set(portal.position.x, portal.position.y + 0.5, portal.position.z);
    _portalDummy.rotation.set(Math.PI / 2, portal.rotation.y || 0, 0);
    _portalDummy.updateMatrix();
    _portalIM.setMatrixAt(i, _portalDummy.matrix);
  });

  _portalIM.instanceColor.needsUpdate = true;
  _portalIM.instanceMatrix.needsUpdate = true;
  portalGroup.add(_portalIM);
}

/** Update per-instance colors after a portal health check. */
export function refreshPortalInstanceColors() {
  if (!_portalIM) return;
  portals.forEach((portal, i) => {
    const brightness = portal.status === 'online' ? 0.7 : 0.15;
    _portalColor.set(portal.color).convertSRGBToLinear().multiplyScalar(brightness);
    _portalIM.setColorAt(i, _portalColor);
  });
  _portalIM.instanceColor.needsUpdate = true;
}

// rebuildGravityZones forward ref
let _rebuildGravityZonesFn = null;
export function setRebuildGravityZonesFn(fn) { _rebuildGravityZonesFn = fn; }

// runPortalHealthChecks forward ref
let _runPortalHealthChecksFn = null;
export function setRunPortalHealthChecksFn(fn) { _runPortalHealthChecksFn = fn; }

export async function loadPortals() {
  try {
    const res = await fetch('./portals.json');
    if (!res.ok) throw new Error('Portals not found');
    portals = await res.json();
    console.log('Loaded portals:', portals);
    setPortalsRef(portals);
    setPortalsRefAudio(portals);
    createPortals();
    rebuildRuneRing();
    if (_rebuildGravityZonesFn) _rebuildGravityZonesFn();
    startPortalHums();
    if (_runPortalHealthChecksFn) _runPortalHealthChecksFn();
  } catch (error) {
    console.error('Failed to load portals:', error);
  }
}