chore: ECMAScript 2016, replace Math.pow by exponentiation operator (**)

.eslintrc.js

@@ -7,7 +7,7 @@ module.exports = {
    'eslint-config-airbnb-base/rules/strict',
  ],
   parserOptions: {
-    ecmaVersion: 6,
+    ecmaVersion: 7,
     sourceType: 'module',
     ecmaFeatures: {
       impliedStrict: true

src/Controls/GlobeControls.js

@@ -223,7 +223,7 @@ function GlobeControls(view, targetCoordinate, range, globeRadius, options = {})
     };
 
     this.getDollyScale = function getDollyScale() {
-        return Math.pow(0.95, this.zoomSpeed);
+        return 0.95 ** this.zoomSpeed;
     };
 
     this.rotateLeft = function rotateLeft(angle = 0) {

src/Controls/PlanarControls.js

@@ -868,7 +868,7 @@ function onContextMenu(event) {
 function smooth(value) {
     // p between 1.0 and 1.5 (empirical)
     const p = 1.20;
-    return Math.pow((value * value * (3 - 2 * value)), p);
+    return (value ** 2 * (3 - 2 * value)) ** p;
 }
 
 export default PlanarControls;

src/Core/Geographic/Extent.js

@@ -88,7 +88,7 @@ Extent.prototype.as = function as(crs) {
     if (this.isTiledCrs()) {
         if (this._crs == 'WMTS:PM' || this._crs == 'TMS') {
             // Convert this to the requested crs by using 4326 as an intermediate state.
-            const nbCol = Math.pow(2, this.zoom);
+            const nbCol = 2 ** this.zoom;
             const nbRow = nbCol;
             const sizeRow = 1.0 / nbRow;
             // convert row PM to Y PM
@@ -120,7 +120,7 @@ Extent.prototype.as = function as(crs) {
                 }
             }
         } else if (this._crs == 'WMTS:WGS84G' && crs == 'EPSG:4326') {
-            const nbRow = Math.pow(2, this.zoom);
+            const nbRow = 2 ** this.zoom;
             const size = 180 / nbRow;
             const north = size * (nbRow - this.row) - 90;
             const south = size * (nbRow - (this.row + 1)) - 90;
@@ -177,7 +177,7 @@ Extent.prototype.offsetToParent = function offsetToParent(other, target = new TH
     }
     if (this.isTiledCrs()) {
         const diffLevel = this.zoom - other.zoom;
-        const diff = Math.pow(2, diffLevel);
+        const diff = 2 ** diffLevel;
         const invDiff = 1 / diff;
 
         const r = (this.row - (this.row % diff)) * invDiff;
@@ -286,7 +286,7 @@ Extent.prototype.isInside = function isInside(other, epsilon) {
             return false;
         } else {
             const diffLevel = this.zoom - other.zoom;
-            const diff = Math.pow(2, diffLevel);
+            const diff = 2 ** diffLevel;
             const invDiff = 1 / diff;
 
             const r = (this.row - (this.row % diff)) * invDiff;
@@ -433,7 +433,7 @@ Extent.prototype.extentParent = function extentParent(levelParent) {
     if (this.isTiledCrs()) {
         if (levelParent && levelParent < this.zoom) {
             const diffLevel = this.zoom - levelParent;
-            const diff = Math.pow(2, diffLevel);
+            const diff = 2 ** diffLevel;
             const invDiff = 1 / diff;
 
             const r = (this.row - (this.row % diff)) * invDiff;

src/Core/Geographic/Projection.js

@@ -56,7 +56,7 @@ const Projection = {
         var zoom = Math.floor(
             Math.log(Math.PI / MathExt.degToRad(dim.y)) / LOG_TWO + 0.5);
 
-        var nY = Math.pow(2, zoom);
+        var nY = 2 ** zoom;
         var nX = 2 * nY;
 
         var uX = Math.PI * 2 / nX;
@@ -83,7 +83,7 @@ const Projection = {
 function WMTS_WGS84ToWMTS_PM(cWMTS, bbox) {
     var wmtsBox = [];
     var level = cWMTS.zoom + 1;
-    var nbRow = Math.pow(2, level);
+    var nbRow = 2 ** level;
 
     var sizeRow = 1.0 / nbRow;
 

src/Core/Picking.js

@@ -46,7 +46,7 @@ function screenCoordsToNodeId(view, tileLayer, viewCoords, radius) {
         const idx = (y * 2 * radius + x) * 4;
         const data = buffer.slice(idx, idx + 4);
         depthRGBA.fromArray(data).divideScalar(255.0);
-        const unpack = unpack1K(depthRGBA, Math.pow(256, 3));
+        const unpack = unpack1K(depthRGBA, 256 ** 3);
 
         const _id = Math.round(unpack);
         if (ids.indexOf(_id) < 0) {

src/Core/Prefab/Globe/Atmosphere.js

@@ -90,7 +90,7 @@ Atmosphere.prototype._initRealisticLighning = function _initRealisticLighning()
 
     var uniformsSky = {
         v3LightPosition: { value: LIGHTING_POSITION.clone().normalize() },
-        v3InvWavelength: { value: new THREE.Vector3(1 / Math.pow(atmosphere.wavelength[0], 4), 1 / Math.pow(atmosphere.wavelength[1], 4), 1 / Math.pow(atmosphere.wavelength[2], 4)) },
+        v3InvWavelength: { value: new THREE.Vector3(1 / atmosphere.wavelength[0] ** 4, 1 / atmosphere.wavelength[1] ** 4, 1 / atmosphere.wavelength[2] ** 4) },
         fCameraHeight: { value: 0.0 },
         fCameraHeight2: { value: 0.0 },
         fInnerRadius: { value: atmosphere.innerRadius },

src/Core/Prefab/Globe/BuilderEllipsoidTile.js

@@ -28,7 +28,7 @@ BuilderEllipsoidTile.prototype.constructor = BuilderEllipsoidTile;
 // init projected object -> params.projected
 
 BuilderEllipsoidTile.prototype.Prepare = function Prepare(params) {
-    params.nbRow = Math.pow(2.0, params.level + 1.0);
+    params.nbRow = 2 ** (params.level + 1.0);
 
     var st1 = WGS84ToOneSubY(params.extent.south());
 

src/Core/Prefab/Globe/GlobeLayer.js

@@ -84,7 +84,7 @@ class GlobeLayer extends TiledGeometryLayer {
                 1 / ellipsoidSizes.y,
                 1 / ellipsoidSizes.z));
 
-        subdivisionRatio = 1 / Math.pow(2, this.maxDeltaElevationLevel);
+        subdivisionRatio = 1 / 2 ** this.maxDeltaElevationLevel;
     }
 
     preUpdate(context, changeSources) {
@@ -202,7 +202,7 @@ class GlobeLayer extends TiledGeometryLayer {
         let sinus = distance * preSinus;
         let zoom = Math.log(Math.PI / (2.0 * Math.asin(sinus))) / Math.log(2);
 
-        const delta = Math.PI / Math.pow(2, zoom);
+        const delta = Math.PI / 2 ** zoom;
         const circleChord = 2.0 * ellipsoidSizes.x * Math.sin(delta * 0.5);
         const radius = circleChord * 0.5;
 
@@ -214,7 +214,7 @@ class GlobeLayer extends TiledGeometryLayer {
     }
 
     computeDistanceCameraFromTileZoom(zoom, camera) {
-        const delta = Math.PI / Math.pow(2, zoom);
+        const delta = Math.PI / 2 ** zoom;
         const circleChord = 2.0 * ellipsoidSizes.x * Math.sin(delta * 0.5);
         const radius = circleChord * 0.5;
         const error = radius / SIZE_TEXTURE_TILE;

src/Core/Prefab/GlobeView.js

@@ -170,7 +170,7 @@ function GlobeView(viewerDiv, coordCarto, options = {}) {
 
         // Compute fog distance, this function makes it possible to have a shorter distance
         // when the camera approaches the ground
-        this.fogDistance = mfogDistance * Math.pow((len - ellipsoidSizes.x * 0.99) * 0.25 / ellipsoidSizes.x, 1.5);
+        this.fogDistance = mfogDistance * ((len - ellipsoidSizes.x * 0.99) * 0.25 / ellipsoidSizes.x) ** 1.5;
 
         // get altitude camera
         coordCam.set(this.referenceCrs, this.camera.camera3D.position).as('EPSG:4326', coordGeoCam);

src/Core/Prefab/Planar/PlanarLayer.js

@@ -70,7 +70,7 @@ class PlanarLayer extends TiledGeometryLayer {
                 const offsetScale = nodeLayer.offsetScales[0];
                 const ratio = offsetScale.z;
                 // ratio is node size / texture size
-                if (ratio < 1 / Math.pow(2, maxDeltaElevationLevel)) {
+                if (ratio < 1 / (2 ** maxDeltaElevationLevel)) {
                     return false;
                 }
             }

src/Core/Prefab/Planar/PlanarTileBuilder.js

@@ -18,7 +18,7 @@ PlanarTileBuilder.prototype.constructor = PlanarTileBuilder;
 // prepare params
 // init projected object -> params.projected
 PlanarTileBuilder.prototype.Prepare = function Prepare(params) {
-    params.nbRow = Math.pow(2.0, params.zoom + 1.0);
+    params.nbRow = 2 ** (params.zoom + 1.0);
     params.projected = new THREE.Vector3();
 };
 

src/Parser/VectorTileParser.js

@@ -59,7 +59,7 @@ function project(line, ox, oy, size) {
 }
 
 function toGeoJSON(x, y, z) {
-    const size = this.extent * Math.pow(2, z);
+    const size = this.extent * 2 ** z;
     const x0 = this.extent * x;
     const y0 = this.extent * y;
     let coords = this.loadGeometry();

src/Process/PointCloudProcessing.js

@@ -60,7 +60,7 @@ function computeScreenSpaceError(context, layer, elt, distance) {
     if (distance <= 0) {
         return Infinity;
     }
-    const pointSpacing = layer.metadata.spacing / Math.pow(2, elt.name.length);
+    const pointSpacing = layer.metadata.spacing / 2 ** elt.name.length;
     // Estimate the onscreen distance between 2 points
     const onScreenSpacing = context.camera.preSSE * pointSpacing / distance;
     // [  P1  ]--------------[   P2   ]

src/Renderer/c3DEngine.js

@@ -256,7 +256,7 @@ c3DEngine.prototype.depthBufferRGBAValueToOrthoZ = function depthBufferRGBAValue
         const gl_FragDepthEXT = unpack1K(depthRGBA);
         const logDepthBufFC = 2.0 / (Math.log(camera.far + 1.0) / Math.LN2);
         // invert function : gl_FragDepthEXT = log2(vFragDepth) * logDepthBufFC * 0.5;
-        return Math.pow(2.0, 2.0 * gl_FragDepthEXT / logDepthBufFC);
+        return 2 ** (2 * gl_FragDepthEXT / logDepthBufFC);
     } else {
         let gl_FragCoord_Z = unpack1K(depthRGBA);
         gl_FragCoord_Z = gl_FragCoord_Z * 2.0 - 1.0;