three - 灯光

灯光

• AmbientLight：环境光，均匀照亮场景种所有物体
• DirectionalLight：平行光，平行的光线，比如太阳光
• PointLight：点光源，从一个点发射的光源，比如灯泡
• SpotLight：聚光灯，照射出一个圆锥体，比如手电筒，舞台的灯光
• HemisphereLight：半球光，两种颜色的光，比如天空颜色、地面颜色相互叠加
• RectAreaLight：矩形平面光，类似窗户、LED 灯管等从一个面发光的效果

平行光

一般用来模拟太阳光，背面不可见

export const light = new THREE.DirectionalLight(0xffffff); 
light.position.set(400, 500, 300); 
light.lookAt(0, 0, 0);

const helper = new THREE.DirectionalLightHelper(light, 100);
mesh.add(helper);

点光源

背面不可见

export const light = new THREE.PointLight(0xffffff, 1000000); 
light.position.set(400, 500, 300); 
light.lookAt(0, 0, 0); 

const helper = new THREE.PointLightHelper(light, 100); 
mesh.add(helper);

环境光

背面可见

const ambientLight = new THREE.AmbientLight(0xffffff); 
mesh.add(ambientLight);

聚光灯

export const light = new THREE.SpotLight(0xffffff, 1000000);
light.distance = 1000; light.angle = Math.PI / 6; 
light.position.set(400, 500, 300); 
light.lookAt(0, 0, 0); 

const helper = new THREE.SpotLightHelper(light); 
mesh.add(helper);

半球光

export const light = new THREE.HemisphereLight( 
    new THREE.Color('orange'), 
    new THREE.Color('green'),
    1 
); 
light.position.set(400, 500, 300); 
light.lookAt(0, 0, 0); 

const helper = new THREE.HemisphereLightHelper(light, 100); 
mesh.add(helper);

矩形平面光

只对MeshStandardMaterial生效

export const light = new THREE.RectAreaLight( new THREE.Color('red'), 20, 100, 100 ); 
light.position.set(400, 500, 300);
light.lookAt(0, 0, 0); 

const helper = new RectAreaLightHelper(light); 
mesh.add(helper);