import * as THREE from 'three';import {GLTFLoader} from './vendor/three/loaders/GLTFLoader.js';import {OrbitControls} from './vendor/three/controls/OrbitControls.js';import {RoomEnvironment} from './vendor/three/environments/RoomEnvironment.js';
const panel=document.querySelector('#figure-3');if(panel){const stage=panel.querySelector('.scene-stage'),select=panel.querySelector('#model-select'),mode=panel.querySelector('#scene-mode'),slider=panel.querySelector('#scene-split'),divider=panel.querySelector('.scene-divider'),status=panel.querySelector('.scene-status'),left=panel.querySelector('.scene-label-left'),right=panel.querySelector('.scene-label-right'),zh=document.documentElement.lang.startsWith('zh');let started=false,active=false,renderer,camera,controls,environment,manifest,selectedScene,truthScene,resizeObserver,split=.5,version=0;const cache=new Map();const setStatus=(text,error=false)=>{status.textContent=text;status.hidden=!text;status.classList.toggle('error',error);panel.dataset.state=error?'error':text?'loading':'ready'};
function render(){if(!renderer||!selectedScene)return;const w=stage.clientWidth,h=stage.clientHeight;renderer.setScissorTest(false);renderer.setViewport(0,0,w,h);renderer.clear();if(mode.value==='single'||select.value==='GT'||!truthScene){renderer.render(selectedScene,camera);return}const x=Math.round(w*split);renderer.setScissorTest(true);renderer.setScissor(0,0,x,h);renderer.render(selectedScene,camera);renderer.setScissor(x,0,w-x,h);renderer.render(truthScene,camera);renderer.setScissorTest(false)}
function updateMode(){const comparing=mode.value==='compare'&&select.value!=='GT';panel.classList.toggle('is-comparing',comparing);slider.disabled=!comparing;divider.hidden=!comparing;right.hidden=!comparing;left.textContent=select.value;render()}function updateSplit(value){split=Math.max(.02,Math.min(.98,Number(value)/100));slider.value=String(Math.round(split*100));stage.style.setProperty('--split',`${split*100}%`);divider.setAttribute('aria-valuenow',slider.value);render()}
function resetCamera(){if(!camera||!manifest)return;const v=manifest.camera;controls.target.fromArray(v.target);camera.position.fromArray(v.position).sub(controls.target).multiplyScalar(Math.max(1,1.5/(stage.clientWidth/stage.clientHeight))).add(controls.target);camera.near=v.near;camera.far=v.far;camera.fov=v.fov;camera.updateProjectionMatrix();controls.update();render()}function resize(){if(!renderer)return;const w=stage.clientWidth,h=stage.clientHeight;renderer.setSize(w,h,false);const oldFit=Math.max(1,1.5/camera.aspect);camera.aspect=w/h;if(controls)camera.position.sub(controls.target).multiplyScalar(Math.max(1,1.5/camera.aspect)/oldFit).add(controls.target);camera.updateProjectionMatrix();render()}
function loadScene(id){if(!cache.has(id)){const promise=new GLTFLoader().loadAsync(manifest.models[id].url).then(gltf=>{const scene=new THREE.Scene();scene.background=new THREE.Color('#e9ede5');scene.environment=environment;scene.add(new THREE.HemisphereLight(0xffffff,0x68746b,2));const sun=new THREE.DirectionalLight(0xffffff,2.3);sun.position.set(12,25,18);scene.add(sun);let hiddenCutaway=0;if(id!=='GT'){const rows=manifest.models[id].runtime_matrix_gltf_y_up;gltf.scene.applyMatrix4(new THREE.Matrix4().set(...rows.flat()));gltf.scene.traverse(node=>{const name=node.name||'',isShell=/(ceiling|roof|wall|facade)/i.test(name),isDetail=/(emblem|art|grass|metal)/i.test(name);if(isShell&&!isDetail){node.visible=false;hiddenCutaway++}})}scene.add(gltf.scene);const bounds=new THREE.Box3().setFromObject(gltf.scene);scene.userData.method=id;scene.userData.hiddenCutaway=hiddenCutaway;scene.userData.bounds={min:bounds.min.toArray(),max:bounds.max.toArray()};return scene}).catch(e=>{cache.delete(id);throw e});cache.set(id,promise)}return cache.get(id)}
async function selectScene(){if(!manifest)return;const request=++version,id=select.value;setStatus(zh?`正在加载 ${id}…`:`Loading ${id}…`);try{const [model,gt]=await Promise.all([loadScene(id),loadScene('GT')]);if(request!==version)return;selectedScene=model;truthScene=gt;setStatus('');updateMode();panel.dataset.loadedModel=id;panel.dataset.gtLoaded='true'}catch(e){if(request!==version)return;console.error('Scene asset load failed',e);setStatus(zh?'场景加载失败，请重试。':'Scene loading failed. Retry.',true)}}
async function start(){if(started)return;started=true;try{setStatus(zh?'正在加载对比场景…':'Loading comparison scenes…');const response=await fetch('data/scene_comparison.json', {cache:'no-store'});if(!response.ok)throw Error(`manifest HTTP ${response.status}`);manifest=await response.json();renderer=new THREE.WebGLRenderer({antialias:true});renderer.setPixelRatio(Math.min(devicePixelRatio,1.5));renderer.toneMapping=THREE.ACESFilmicToneMapping;renderer.outputColorSpace=THREE.SRGBColorSpace;renderer.domElement.setAttribute('aria-label',zh?'重建与 GT 三维场景':'Reconstruction and GT 3D scene');renderer.domElement.tabIndex=0;stage.prepend(renderer.domElement);camera=new THREE.PerspectiveCamera(42,1,.05,500);controls=new OrbitControls(camera,renderer.domElement);controls.enableDamping=false;controls.minDistance=1;controls.maxDistance=200;controls.addEventListener('change',render);const pmrem=new THREE.PMREMGenerator(renderer),room=new RoomEnvironment();environment=pmrem.fromScene(room,.04).texture;room.dispose();pmrem.dispose();resizeObserver=new ResizeObserver(resize);resizeObserver.observe(stage);resize();resetCamera();panel.sceneDiagnostics=()=>({selected:select.value,loaded:selectedScene?.userData.method,gtLoaded:!!truthScene,hiddenCutaway:selectedScene?.userData.hiddenCutaway||0,bounds:selectedScene?.userData.bounds,camera:camera.position.toArray(),target:controls.target.toArray(),split,mode:mode.value,singleCamera:true,singleViewport:true,coordinateConversion:manifest.coordinate_conversion,cachedModels:[...cache.keys()]});await selectScene()}catch(e){console.error('Scene comparison initialization failed',e);resizeObserver?.disconnect();controls?.dispose();environment?.dispose();renderer?.dispose();renderer?.domElement.remove();renderer=camera=controls=environment=manifest=undefined;selectedScene=truthScene=undefined;cache.clear();started=false;setStatus(zh?'无法启动三维场景，请重试。':'Unable to start 3D viewer. Retry.',true)}}
select.addEventListener('change',()=>{updateMode();selectScene()});mode.addEventListener('change',updateMode);slider.addEventListener('input',()=>updateSplit(slider.value));panel.querySelector('#scene-reset').addEventListener('click',resetCamera);panel.querySelector('#scene-retry').addEventListener('click',()=>manifest&&renderer?selectScene():start());divider.addEventListener('pointerdown',e=>{e.preventDefault();active=true;divider.setPointerCapture(e.pointerId);if(controls)controls.enabled=false});divider.addEventListener('pointermove',e=>{if(!active)return;const b=stage.getBoundingClientRect();updateSplit((e.clientX-b.left)/b.width*100)});const stop=()=>{active=false;if(controls)controls.enabled=true};divider.addEventListener('pointerup',stop);divider.addEventListener('pointercancel',stop);divider.addEventListener('keydown',e=>{const d={ArrowLeft:-2,ArrowRight:2,PageDown:-10,PageUp:10};if(e.key in d){e.preventDefault();updateSplit(split*100+d[e.key])}});updateSplit(50);updateMode();const lazy=new IntersectionObserver(es=>{if(es.some(e=>e.isIntersecting)){lazy.disconnect();start()}},{rootMargin:'300px'});lazy.observe(panel)}