import AttributeCompression from "./AttributeCompression.js";
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import Cartesian2 from "./Cartesian2.js";
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import Cartesian3 from "./Cartesian3.js";
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import ComponentDatatype from "./ComponentDatatype.js";
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import defaultValue from "./defaultValue.js";
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import defined from "./defined.js";
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import CesiumMath from "./Math.js";
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import Matrix4 from "./Matrix4.js";
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import TerrainExaggeration from "./TerrainExaggeration.js";
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import TerrainQuantization from "./TerrainQuantization.js";
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var cartesian3Scratch = new Cartesian3();
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var cartesian3DimScratch = new Cartesian3();
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var cartesian2Scratch = new Cartesian2();
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var matrix4Scratch = new Matrix4();
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var matrix4Scratch2 = new Matrix4();
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var SHIFT_LEFT_12 = Math.pow(2.0, 12.0);
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/**
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* Data used to quantize and pack the terrain mesh. The position can be unpacked for picking and all attributes
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* are unpacked in the vertex shader.
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*
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* @alias TerrainEncoding
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* @constructor
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*
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* @param {Cartesian3} center The center point of the vertices.
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* @param {AxisAlignedBoundingBox} axisAlignedBoundingBox The bounds of the tile in the east-north-up coordinates at the tiles center.
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* @param {Number} minimumHeight The minimum height.
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* @param {Number} maximumHeight The maximum height.
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* @param {Matrix4} fromENU The east-north-up to fixed frame matrix at the center of the terrain mesh.
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* @param {Boolean} hasVertexNormals If the mesh has vertex normals.
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* @param {Boolean} [hasWebMercatorT=false] true if the terrain data includes a Web Mercator texture coordinate; otherwise, false.
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* @param {Boolean} [hasGeodeticSurfaceNormals=false] true if the terrain data includes geodetic surface normals; otherwise, false.
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* @param {Number} [exaggeration=1.0] A scalar used to exaggerate terrain.
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* @param {Number} [exaggerationRelativeHeight=0.0] The relative height from which terrain is exaggerated.
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*
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* @private
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*/
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function TerrainEncoding(
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center,
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axisAlignedBoundingBox,
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minimumHeight,
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maximumHeight,
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fromENU,
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hasVertexNormals,
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hasWebMercatorT,
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hasGeodeticSurfaceNormals,
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exaggeration,
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exaggerationRelativeHeight
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) {
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var quantization = TerrainQuantization.NONE;
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var toENU;
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var matrix;
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if (
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defined(axisAlignedBoundingBox) &&
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defined(minimumHeight) &&
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defined(maximumHeight) &&
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defined(fromENU)
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) {
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var minimum = axisAlignedBoundingBox.minimum;
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var maximum = axisAlignedBoundingBox.maximum;
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var dimensions = Cartesian3.subtract(
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maximum,
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minimum,
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cartesian3DimScratch
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);
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var hDim = maximumHeight - minimumHeight;
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var maxDim = Math.max(Cartesian3.maximumComponent(dimensions), hDim);
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if (maxDim < SHIFT_LEFT_12 - 1.0) {
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quantization = TerrainQuantization.BITS12;
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} else {
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quantization = TerrainQuantization.NONE;
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}
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toENU = Matrix4.inverseTransformation(fromENU, new Matrix4());
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var translation = Cartesian3.negate(minimum, cartesian3Scratch);
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Matrix4.multiply(
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Matrix4.fromTranslation(translation, matrix4Scratch),
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toENU,
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toENU
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);
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var scale = cartesian3Scratch;
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scale.x = 1.0 / dimensions.x;
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scale.y = 1.0 / dimensions.y;
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scale.z = 1.0 / dimensions.z;
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Matrix4.multiply(Matrix4.fromScale(scale, matrix4Scratch), toENU, toENU);
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matrix = Matrix4.clone(fromENU);
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Matrix4.setTranslation(matrix, Cartesian3.ZERO, matrix);
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fromENU = Matrix4.clone(fromENU, new Matrix4());
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var translationMatrix = Matrix4.fromTranslation(minimum, matrix4Scratch);
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var scaleMatrix = Matrix4.fromScale(dimensions, matrix4Scratch2);
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var st = Matrix4.multiply(translationMatrix, scaleMatrix, matrix4Scratch);
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Matrix4.multiply(fromENU, st, fromENU);
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Matrix4.multiply(matrix, st, matrix);
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}
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/**
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* How the vertices of the mesh were compressed.
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* @type {TerrainQuantization}
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*/
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this.quantization = quantization;
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/**
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* The minimum height of the tile including the skirts.
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* @type {Number}
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*/
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this.minimumHeight = minimumHeight;
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/**
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* The maximum height of the tile.
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* @type {Number}
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*/
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this.maximumHeight = maximumHeight;
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/**
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* The center of the tile.
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* @type {Cartesian3}
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*/
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this.center = Cartesian3.clone(center);
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/**
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* A matrix that takes a vertex from the tile, transforms it to east-north-up at the center and scales
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* it so each component is in the [0, 1] range.
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* @type {Matrix4}
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*/
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this.toScaledENU = toENU;
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/**
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* A matrix that restores a vertex transformed with toScaledENU back to the earth fixed reference frame
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* @type {Matrix4}
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*/
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this.fromScaledENU = fromENU;
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/**
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* The matrix used to decompress the terrain vertices in the shader for RTE rendering.
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* @type {Matrix4}
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*/
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this.matrix = matrix;
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/**
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* The terrain mesh contains normals.
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* @type {Boolean}
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*/
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this.hasVertexNormals = hasVertexNormals;
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/**
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* The terrain mesh contains a vertical texture coordinate following the Web Mercator projection.
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* @type {Boolean}
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*/
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this.hasWebMercatorT = defaultValue(hasWebMercatorT, false);
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/**
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* The terrain mesh contains geodetic surface normals, used for terrain exaggeration.
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* @type {Boolean}
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*/
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this.hasGeodeticSurfaceNormals = defaultValue(
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hasGeodeticSurfaceNormals,
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false
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);
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/**
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* A scalar used to exaggerate terrain.
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* @type {Number}
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*/
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this.exaggeration = defaultValue(exaggeration, 1.0);
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/**
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* The relative height from which terrain is exaggerated.
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*/
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this.exaggerationRelativeHeight = defaultValue(
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exaggerationRelativeHeight,
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0.0
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);
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/**
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* The number of components in each vertex. This value can differ with different quantizations.
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* @type {Number}
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*/
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this.stride = 0;
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this._offsetGeodeticSurfaceNormal = 0;
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this._offsetVertexNormal = 0;
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// Calculate the stride and offsets declared above
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this._calculateStrideAndOffsets();
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}
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TerrainEncoding.prototype.encode = function (
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vertexBuffer,
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bufferIndex,
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position,
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uv,
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height,
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normalToPack,
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webMercatorT,
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geodeticSurfaceNormal
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) {
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var u = uv.x;
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var v = uv.y;
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if (this.quantization === TerrainQuantization.BITS12) {
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position = Matrix4.multiplyByPoint(
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this.toScaledENU,
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position,
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cartesian3Scratch
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);
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position.x = CesiumMath.clamp(position.x, 0.0, 1.0);
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position.y = CesiumMath.clamp(position.y, 0.0, 1.0);
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position.z = CesiumMath.clamp(position.z, 0.0, 1.0);
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var hDim = this.maximumHeight - this.minimumHeight;
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var h = CesiumMath.clamp((height - this.minimumHeight) / hDim, 0.0, 1.0);
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Cartesian2.fromElements(position.x, position.y, cartesian2Scratch);
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var compressed0 = AttributeCompression.compressTextureCoordinates(
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cartesian2Scratch
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);
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Cartesian2.fromElements(position.z, h, cartesian2Scratch);
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var compressed1 = AttributeCompression.compressTextureCoordinates(
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cartesian2Scratch
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);
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Cartesian2.fromElements(u, v, cartesian2Scratch);
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var compressed2 = AttributeCompression.compressTextureCoordinates(
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cartesian2Scratch
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);
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vertexBuffer[bufferIndex++] = compressed0;
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vertexBuffer[bufferIndex++] = compressed1;
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vertexBuffer[bufferIndex++] = compressed2;
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if (this.hasWebMercatorT) {
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Cartesian2.fromElements(webMercatorT, 0.0, cartesian2Scratch);
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var compressed3 = AttributeCompression.compressTextureCoordinates(
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cartesian2Scratch
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);
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vertexBuffer[bufferIndex++] = compressed3;
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}
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} else {
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Cartesian3.subtract(position, this.center, cartesian3Scratch);
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vertexBuffer[bufferIndex++] = cartesian3Scratch.x;
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vertexBuffer[bufferIndex++] = cartesian3Scratch.y;
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vertexBuffer[bufferIndex++] = cartesian3Scratch.z;
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vertexBuffer[bufferIndex++] = height;
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vertexBuffer[bufferIndex++] = u;
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vertexBuffer[bufferIndex++] = v;
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if (this.hasWebMercatorT) {
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vertexBuffer[bufferIndex++] = webMercatorT;
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}
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}
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if (this.hasVertexNormals) {
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vertexBuffer[bufferIndex++] = AttributeCompression.octPackFloat(
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normalToPack
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);
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}
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if (this.hasGeodeticSurfaceNormals) {
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vertexBuffer[bufferIndex++] = geodeticSurfaceNormal.x;
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vertexBuffer[bufferIndex++] = geodeticSurfaceNormal.y;
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vertexBuffer[bufferIndex++] = geodeticSurfaceNormal.z;
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}
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return bufferIndex;
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};
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var scratchPosition = new Cartesian3();
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var scratchGeodeticSurfaceNormal = new Cartesian3();
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TerrainEncoding.prototype.addGeodeticSurfaceNormals = function (
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oldBuffer,
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newBuffer,
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ellipsoid
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) {
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if (this.hasGeodeticSurfaceNormals) {
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return;
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}
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var oldStride = this.stride;
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var vertexCount = oldBuffer.length / oldStride;
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this.hasGeodeticSurfaceNormals = true;
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this._calculateStrideAndOffsets();
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var newStride = this.stride;
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for (var index = 0; index < vertexCount; index++) {
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for (var offset = 0; offset < oldStride; offset++) {
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var oldIndex = index * oldStride + offset;
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var newIndex = index * newStride + offset;
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newBuffer[newIndex] = oldBuffer[oldIndex];
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}
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var position = this.decodePosition(newBuffer, index, scratchPosition);
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var geodeticSurfaceNormal = ellipsoid.geodeticSurfaceNormal(
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position,
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scratchGeodeticSurfaceNormal
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);
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var bufferIndex = index * newStride + this._offsetGeodeticSurfaceNormal;
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newBuffer[bufferIndex] = geodeticSurfaceNormal.x;
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newBuffer[bufferIndex + 1] = geodeticSurfaceNormal.y;
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newBuffer[bufferIndex + 2] = geodeticSurfaceNormal.z;
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}
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};
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TerrainEncoding.prototype.removeGeodeticSurfaceNormals = function (
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oldBuffer,
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newBuffer
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) {
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if (!this.hasGeodeticSurfaceNormals) {
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return;
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}
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var oldStride = this.stride;
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var vertexCount = oldBuffer.length / oldStride;
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this.hasGeodeticSurfaceNormals = false;
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this._calculateStrideAndOffsets();
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var newStride = this.stride;
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for (var index = 0; index < vertexCount; index++) {
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for (var offset = 0; offset < newStride; offset++) {
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var oldIndex = index * oldStride + offset;
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var newIndex = index * newStride + offset;
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newBuffer[newIndex] = oldBuffer[oldIndex];
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}
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}
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};
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TerrainEncoding.prototype.decodePosition = function (buffer, index, result) {
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if (!defined(result)) {
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result = new Cartesian3();
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}
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index *= this.stride;
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if (this.quantization === TerrainQuantization.BITS12) {
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var xy = AttributeCompression.decompressTextureCoordinates(
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buffer[index],
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cartesian2Scratch
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);
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result.x = xy.x;
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result.y = xy.y;
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var zh = AttributeCompression.decompressTextureCoordinates(
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buffer[index + 1],
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cartesian2Scratch
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);
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result.z = zh.x;
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return Matrix4.multiplyByPoint(this.fromScaledENU, result, result);
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}
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result.x = buffer[index];
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result.y = buffer[index + 1];
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result.z = buffer[index + 2];
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return Cartesian3.add(result, this.center, result);
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};
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TerrainEncoding.prototype.getExaggeratedPosition = function (
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buffer,
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index,
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result
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) {
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result = this.decodePosition(buffer, index, result);
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var exaggeration = this.exaggeration;
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var exaggerationRelativeHeight = this.exaggerationRelativeHeight;
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var hasExaggeration = exaggeration !== 1.0;
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if (hasExaggeration && this.hasGeodeticSurfaceNormals) {
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var geodeticSurfaceNormal = this.decodeGeodeticSurfaceNormal(
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buffer,
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index,
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scratchGeodeticSurfaceNormal
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);
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var rawHeight = this.decodeHeight(buffer, index);
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var heightDifference =
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TerrainExaggeration.getHeight(
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rawHeight,
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exaggeration,
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exaggerationRelativeHeight
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) - rawHeight;
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// some math is unrolled for better performance
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result.x += geodeticSurfaceNormal.x * heightDifference;
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result.y += geodeticSurfaceNormal.y * heightDifference;
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result.z += geodeticSurfaceNormal.z * heightDifference;
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}
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return result;
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};
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TerrainEncoding.prototype.decodeTextureCoordinates = function (
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buffer,
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index,
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result
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) {
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if (!defined(result)) {
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result = new Cartesian2();
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}
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index *= this.stride;
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if (this.quantization === TerrainQuantization.BITS12) {
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return AttributeCompression.decompressTextureCoordinates(
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buffer[index + 2],
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result
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);
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}
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return Cartesian2.fromElements(buffer[index + 4], buffer[index + 5], result);
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};
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TerrainEncoding.prototype.decodeHeight = function (buffer, index) {
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index *= this.stride;
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if (this.quantization === TerrainQuantization.BITS12) {
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var zh = AttributeCompression.decompressTextureCoordinates(
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buffer[index + 1],
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cartesian2Scratch
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);
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return (
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zh.y * (this.maximumHeight - this.minimumHeight) + this.minimumHeight
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);
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}
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return buffer[index + 3];
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};
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TerrainEncoding.prototype.decodeWebMercatorT = function (buffer, index) {
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index *= this.stride;
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if (this.quantization === TerrainQuantization.BITS12) {
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return AttributeCompression.decompressTextureCoordinates(
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buffer[index + 3],
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cartesian2Scratch
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).x;
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}
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return buffer[index + 6];
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};
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TerrainEncoding.prototype.getOctEncodedNormal = function (
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buffer,
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index,
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result
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) {
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index = index * this.stride + this._offsetVertexNormal;
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var temp = buffer[index] / 256.0;
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var x = Math.floor(temp);
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var y = (temp - x) * 256.0;
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return Cartesian2.fromElements(x, y, result);
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};
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TerrainEncoding.prototype.decodeGeodeticSurfaceNormal = function (
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buffer,
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index,
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result
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) {
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index = index * this.stride + this._offsetGeodeticSurfaceNormal;
|
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result.x = buffer[index];
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result.y = buffer[index + 1];
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result.z = buffer[index + 2];
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return result;
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};
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TerrainEncoding.prototype._calculateStrideAndOffsets = function () {
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var vertexStride = 0;
|
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switch (this.quantization) {
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case TerrainQuantization.BITS12:
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vertexStride += 3;
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break;
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default:
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vertexStride += 6;
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}
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if (this.hasWebMercatorT) {
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vertexStride += 1;
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}
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if (this.hasVertexNormals) {
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this._offsetVertexNormal = vertexStride;
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vertexStride += 1;
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}
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if (this.hasGeodeticSurfaceNormals) {
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this._offsetGeodeticSurfaceNormal = vertexStride;
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vertexStride += 3;
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}
|
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this.stride = vertexStride;
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};
|
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var attributesIndicesNone = {
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position3DAndHeight: 0,
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textureCoordAndEncodedNormals: 1,
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geodeticSurfaceNormal: 2,
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};
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var attributesIndicesBits12 = {
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compressed0: 0,
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compressed1: 1,
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geodeticSurfaceNormal: 2,
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};
|
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TerrainEncoding.prototype.getAttributes = function (buffer) {
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var datatype = ComponentDatatype.FLOAT;
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var sizeInBytes = ComponentDatatype.getSizeInBytes(datatype);
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var strideInBytes = this.stride * sizeInBytes;
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var offsetInBytes = 0;
|
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var attributes = [];
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function addAttribute(index, componentsPerAttribute) {
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attributes.push({
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index: index,
|
vertexBuffer: buffer,
|
componentDatatype: datatype,
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componentsPerAttribute: componentsPerAttribute,
|
offsetInBytes: offsetInBytes,
|
strideInBytes: strideInBytes,
|
});
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offsetInBytes += componentsPerAttribute * sizeInBytes;
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}
|
|
if (this.quantization === TerrainQuantization.NONE) {
|
addAttribute(attributesIndicesNone.position3DAndHeight, 4);
|
|
var componentsTexCoordAndNormals = 2;
|
componentsTexCoordAndNormals += this.hasWebMercatorT ? 1 : 0;
|
componentsTexCoordAndNormals += this.hasVertexNormals ? 1 : 0;
|
addAttribute(
|
attributesIndicesNone.textureCoordAndEncodedNormals,
|
componentsTexCoordAndNormals
|
);
|
|
if (this.hasGeodeticSurfaceNormals) {
|
addAttribute(attributesIndicesNone.geodeticSurfaceNormal, 3);
|
}
|
} else {
|
// When there is no webMercatorT or vertex normals, the attribute only needs 3 components: x/y, z/h, u/v.
|
// WebMercatorT and vertex normals each take up one component, so if only one of them is present the first
|
// attribute gets a 4th component. If both are present, we need an additional attribute that has 1 component.
|
var usingAttribute0Component4 =
|
this.hasWebMercatorT || this.hasVertexNormals;
|
var usingAttribute1Component1 =
|
this.hasWebMercatorT && this.hasVertexNormals;
|
addAttribute(
|
attributesIndicesBits12.compressed0,
|
usingAttribute0Component4 ? 4 : 3
|
);
|
|
if (usingAttribute1Component1) {
|
addAttribute(attributesIndicesBits12.compressed1, 1);
|
}
|
|
if (this.hasGeodeticSurfaceNormals) {
|
addAttribute(attributesIndicesBits12.geodeticSurfaceNormal, 3);
|
}
|
}
|
|
return attributes;
|
};
|
|
TerrainEncoding.prototype.getAttributeLocations = function () {
|
if (this.quantization === TerrainQuantization.NONE) {
|
return attributesIndicesNone;
|
}
|
return attributesIndicesBits12;
|
};
|
|
TerrainEncoding.clone = function (encoding, result) {
|
if (!defined(encoding)) {
|
return undefined;
|
}
|
if (!defined(result)) {
|
result = new TerrainEncoding();
|
}
|
|
result.quantization = encoding.quantization;
|
result.minimumHeight = encoding.minimumHeight;
|
result.maximumHeight = encoding.maximumHeight;
|
result.center = Cartesian3.clone(encoding.center);
|
result.toScaledENU = Matrix4.clone(encoding.toScaledENU);
|
result.fromScaledENU = Matrix4.clone(encoding.fromScaledENU);
|
result.matrix = Matrix4.clone(encoding.matrix);
|
result.hasVertexNormals = encoding.hasVertexNormals;
|
result.hasWebMercatorT = encoding.hasWebMercatorT;
|
result.hasGeodeticSurfaceNormals = encoding.hasGeodeticSurfaceNormals;
|
result.exaggeration = encoding.exaggeration;
|
result.exaggerationRelativeHeight = encoding.exaggerationRelativeHeight;
|
|
result._calculateStrideAndOffsets();
|
|
return result;
|
};
|
export default TerrainEncoding;
|
