THREE.js 三角形是黑色的

Question

所以我使用了 THREE.JS 并创建了一个三角形。 但即使我给它颜色：0xFF0000，它在屏幕上显示为黑色。

这是我的脚本：

var camera, scene, renderer;
var geometry, material, mesh;

init();
animate();

function init() {

    scene = new THREE.Scene();
    camera = new THREE.PerspectiveCamera(35, window.innerWidth / window.innerHeight, 1, 10000);
    camera.position.z = 500;
    scene.add(camera);

    var geometry = new THREE.Geometry(200,200,200);
    var v1 = new THREE.Vector3(200,0,0);   // Vector3 used to specify position
    var v2 = new THREE.Vector3(-100,0,0);
    var v3 = new THREE.Vector3(0,50,0);   // 2d = all vertices in the same plane.. z = 0

    // Push vertices represented by position vectors
    geometry.vertices.push(v1);
    geometry.vertices.push(v2);
    geometry.vertices.push(v3);

    // Push face, defined with vertices in counter clock-wise order
    geometry.faces.push(new THREE.Face3(0, 2, 1));

    // Create a material and combine with geometry to create our mesh
    var redMat = new THREE.MeshLambertMaterial({color: 0xFF0000});
    var triangle = new THREE.Mesh(geometry, redMat);
    scene.add(triangle);

    renderer = new THREE.CanvasRenderer();
    renderer.setSize(window.innerWidth, window.innerHeight);

    document.body.appendChild(renderer.domElement);

}

function animate() {

    requestAnimationFrame(animate);
    render();

}

function render() {

    renderer.render(scene, camera);

}

希望你能找出我犯的错误。 我敢肯定这只是一些非常愚蠢的事情。

Answer 1

聚会迟到了……但对于所有跟随我的人。 这里的问题是使用的材料类型

改变

new THREE.MeshLambertMaterial({color: 0xFF0000});

到

new THREE.MeshBasicMaterial({color: 0xFF0000});

它会显示为红色

Answer 2

甚至我已经为这个问题苦苦挣扎了一段时间。 如果您使用的是 Lambert 材质，我的解决方案是向场景添加环境光。

只需添加：

var light = new THREE.AmbientLight(0xffffff);
scene.add(light);

Answer 3

尝试在几何对象上添加computeFaceNormals调用：

geometry.computeFaceNormals();

*来自https://stackoverflow.com/a/49226898/2154075