SpotLight --> DirectionalLight

A SpotLight must have its distance set in real world coordinates.
This was resulting in very dark scenes, where the position of the light or its intensity must take into account the bounding box.
Directional Lights do not require this settings. They light the scene in a uniform manner from afar.

src/viewer/viewer.ts

@@ -14,7 +14,7 @@ import {
   ShaderMaterial,
   PlaneGeometry,
   Scene, Mesh, Group, Object3D, Uniform,
-  Fog, SpotLight, AmbientLight,
+  Fog, DirectionalLight, AmbientLight,
   BufferGeometry, BufferAttribute,
   LineSegments, ColorSpace
 } from 'three'
@@ -203,7 +203,7 @@ export default class Viewer {
   height: number
 
   scene: Scene
-  private spotLight: SpotLight
+  private directionalLight: DirectionalLight
   private ambientLight: AmbientLight
   rotationGroup: Group
   translationGroup: Group
@@ -402,10 +402,10 @@ export default class Viewer {
 
     // light
 
-    this.spotLight = new SpotLight(
+    this.directionalLight = new DirectionalLight(
       this.parameters.lightColor.getHex(), this.parameters.lightIntensity
     )
-    this.scene.add(this.spotLight)
+    this.scene.add(this.directionalLight)
 
     this.ambientLight = new AmbientLight(
       this.parameters.ambientColor.getHex(), this.parameters.ambientIntensity
@@ -1226,11 +1226,11 @@ export default class Viewer {
   }
 
   private __updateLights () {
-    this.spotLight.color.set(this.parameters.lightColor)
-    this.spotLight.intensity = this.parameters.lightIntensity
+    this.directionalLight.color.set(this.parameters.lightColor)
+    this.directionalLight.intensity = this.parameters.lightIntensity
 
     this.distVector.copy(this.camera.position).setLength(this.boundingBoxLength * 100)
-    this.spotLight.position.copy(this.camera.position).add(this.distVector)
+    this.directionalLight.position.copy(this.camera.position).add(this.distVector)
 
     this.ambientLight.color.set(this.parameters.ambientColor)
     this.ambientLight.intensity = this.parameters.ambientIntensity