面向THREE.js的边界框

// 创建一个 Box3 边界框
const boundingBox = new THREE.Box3();

// 设置边界框的最小点和最大点
boundingBox.set(new THREE.Vector3(-1, -1, -1), new THREE.Vector3(1, 1, 1));

// 获取场景中某个物体的边界框
const object = scene.getObjectByName('myObject');
const boundingBox = new THREE.Box3().setFromObject(object);

// 检测两个边界框是否相交
const boundingBox1 = new THREE.Box3().setFromObject(object1);
const boundingBox2 = new THREE.Box3().setFromObject(object2);
const isIntersecting = boundingBox1.intersectsBox(boundingBox2);

// 使用视锥体剔除优化渲染性能
const camera = scene.camera;
const frustum = new THREE.Frustum();
const viewProjectionMatrix = new THREE.Matrix4();

function updateFrustum() {
    viewProjectionMatrix.multiplyMatrices(camera.projectionMatrix, camera.matrixWorldInverse);
    frustum.setFromProjectionMatrix(viewProjectionMatrix);
}

function isInFrustum(object) {
    const boundingBox = new THREE.Box3().setFromObject(object);
    return frustum.intersectsBox(boundingBox);
}

// 在渲染循环中更新视锥体并剔除不在视锥体内的物体
function render() {
    updateFrustum();
    scene.traverse(object => {
        if (object.isMesh && !isInFrustum(object)) {
            object.visible = false;
        } else {
            object.visible = true;
        }
    });
    renderer.render(scene, camera);
}