var EllipseGeometryLibraryEx = (function () {
var EllipseGeometryLibrary = {};
var rotAxis = new Cesium.Cartesian3();
var tempVec = new Cesium.Cartesian3();
var unitQuat = new Cesium.Quaternion();
var rotMtx = new Cesium.Matrix3();
function pointOnEllipsoid(theta, rotation, northVec, eastVec, aSqr, ab, bSqr, mag, unitPos, result) {
var azimuth = theta + rotation;
Cesium.Cartesian3.multiplyByScalar(eastVec, Math.cos(azimuth), rotAxis);
Cesium.Cartesian3.multiplyByScalar(northVec, Math.sin(azimuth), tempVec);
Cesium.Cartesian3.add(rotAxis, tempVec, rotAxis);
var cosThetaSquared = Math.cos(theta);
cosThetaSquared = cosThetaSquared * cosThetaSquared;
var sinThetaSquared = Math.sin(theta);
sinThetaSquared = sinThetaSquared * sinThetaSquared;
var radius = ab / Math.sqrt(bSqr * cosThetaSquared + aSqr * sinThetaSquared);
var angle = radius / mag;
// Create the quaternion to rotate the position vector to the boundary of the ellipse.
Cesium.Quaternion.fromAxisAngle(rotAxis, angle, unitQuat);
Cesium.Matrix3.fromQuaternion(unitQuat, rotMtx);
Cesium.Matrix3.multiplyByVector(rotMtx, unitPos, result);
Cesium.Cartesian3.normalize(result, result);
Cesium.Cartesian3.multiplyByScalar(result, mag, result);
return result;
}
var scratchCartesian1 = new Cesium.Cartesian3();
var scratchCartesian2 = new Cesium.Cartesian3();
var scratchCartesian3 = new Cesium.Cartesian3();
var scratchNormal = new Cesium.Cartesian3();
/**
* Returns the positions raised to the given heights
* @private
*/
EllipseGeometryLibrary.raisePositionsToHeight = function (positions, options, extrude) {
var ellipsoid = options.ellipsoid;
var height = options.height;
var extrudedHeight = options.extrudedHeight;
var size = (extrude) ? positions.length / 3 * 2 : positions.length / 3;
var finalPositions = new Float64Array(size * 3);
var length = positions.length;
var bottomOffset = (extrude) ? length : 0;
for (var i = 0; i < length; i += 3) {
var i1 = i + 1;
var i2 = i + 2;
var position = Cesium.Cartesian3.fromArray(positions, i, scratchCartesian1);
ellipsoid.scaleToGeodeticSurface(position, position);
var extrudedPosition = Cesium.Cartesian3.clone(position, scratchCartesian2);
var normal = ellipsoid.geodeticSurfaceNormal(position, scratchNormal);
var scaledNormal = Cesium.Cartesian3.multiplyByScalar(normal, height, scratchCartesian3);
Cesium.Cartesian3.add(position, scaledNormal, position);
if (extrude) {
Cesium.Cartesian3.multiplyByScalar(normal, extrudedHeight, scaledNormal);
Cesium.Cartesian3.add(extrudedPosition, scaledNormal, extrudedPosition);
finalPositions[i + bottomOffset] = extrudedPosition.x;
finalPositions[i1 + bottomOffset] = extrudedPosition.y;
finalPositions[i2 + bottomOffset] = extrudedPosition.z;
}
finalPositions[i] = position.x;
finalPositions[i1] = position.y;
finalPositions[i2] = position.z;
}
return finalPositions;
};
var unitPosScratch = new Cesium.Cartesian3();
var eastVecScratch = new Cesium.Cartesian3();
var northVecScratch = new Cesium.Cartesian3();
/**
* options.semiMinorAxis：短半轴
* options.semiMajorAxis：长半轴
* options.rotation：旋转角度 弧度
* options.center：中心点 笛卡尔坐标
* options.granularity：粒度 弧度
addFillPositions：是否插值
addEdgePositions：是否添加端点
* Returns an array of positions that make up the ellipse.
* @private
*/
EllipseGeometryLibrary.computeEllipsePositions = function (options, addEdgePositions) {
var semiMinorAxis = options.semiMinorAxis;
var semiMajorAxis = options.semiMajorAxis;
var rotation = options.rotation;//法线
var center = options.center;
var granularity = options.granularity && (typeof options.granularity === "number") ? options.granularity : (Math.PI / 180.0);// 角度间隔
if (granularity > Math.PI / 12.0) { granularity = Math.PI / 12.0; }
if (granularity < Math.PI / 180.0) { granularity = Math.PI / 180.0; }
var aSqr = semiMinorAxis * semiMinorAxis;
var bSqr = semiMajorAxis * semiMajorAxis;
var ab = semiMajorAxis * semiMinorAxis;
var mag = Cesium.Cartesian3.magnitude(center);//模
var unitPos = Cesium.Cartesian3.normalize(center, unitPosScratch);
var eastVec = Cesium.Cartesian3.cross(Cesium.Cartesian3.UNIT_Z, center, eastVecScratch);
eastVec = Cesium.Cartesian3.normalize(eastVec, eastVec);
var northVec = Cesium.Cartesian3.cross(unitPos, eastVec, northVecScratch);
var numPts = 1 + Math.ceil(Cesium.Math.PI_OVER_TWO / granularity);
var deltaTheta = Cesium.Math.PI_OVER_TWO / (numPts - 1);
var theta = Cesium.Math.PI_OVER_TWO - numPts * deltaTheta;
if (theta < 0.0) {
numPts -= Math.ceil(Math.abs(theta) / deltaTheta);
}
var positions = new Array((numPts + 1) * 3);
var positionsdown = new Array((numPts + 1) * 3);
var positionIndex = 0;
var positionsdownIndex = 0;
var position = scratchCartesian1;
var reflectedPosition = scratchCartesian2;
var outerPositionsLength = (numPts * 4) * 3;
var outerRightIndex = outerPositionsLength - 1;
var outerLeftIndex = 0;
var outerPositions = (addEdgePositions) ? new Array(outerPositionsLength) : undefined;
var i;
var j;
var numInterior;
var t;
var interiorPosition;
theta = Cesium.Math.PI_OVER_TWO;
position = pointOnEllipsoid(theta, rotation, northVec, eastVec, aSqr, ab, bSqr, mag, unitPos, position);
positions[positionIndex++] = position.x;
positions[positionIndex++] = position.y;
positions[positionIndex++] = position.z;
if (addEdgePositions) {
outerPositions[outerRightIndex--] = position.z;
outerPositions[outerRightIndex--] = position.y;
outerPositions[outerRightIndex--] = position.x;
}
theta = Cesium.Math.PI_OVER_TWO - deltaTheta;
for (i = 1; i < numPts + 1; ++i) {
position = pointOnEllipsoid(theta, rotation, northVec, eastVec, aSqr, ab, bSqr, mag, unitPos, position);
reflectedPosition = pointOnEllipsoid(Math.PI - theta, rotation, northVec, eastVec, aSqr, ab, bSqr, mag, unitPos, reflectedPosition);
positionsdown[positionsdownIndex++] = position.x;
positionsdown[positionsdownIndex++] = position.y;
positionsdown[positionsdownIndex++] = position.z;
positions[positionIndex++] = reflectedPosition.x;
positions[positionIndex++] = reflectedPosition.y;
positions[positionIndex++] = reflectedPosition.z;
if (addEdgePositions) {
outerPositions[outerRightIndex--] = position.z;
outerPositions[outerRightIndex--] = position.y;
outerPositions[outerRightIndex--] = position.x;
outerPositions[outerLeftIndex++] = reflectedPosition.x;
outerPositions[outerLeftIndex++] = reflectedPosition.y;
outerPositions[outerLeftIndex++] = reflectedPosition.z;
}
theta = Cesium.Math.PI_OVER_TWO - (i + 1) * deltaTheta;
}
for (i = numPts; i > 1; --i) {
theta = Cesium.Math.PI_OVER_TWO
可视域分析(包含引用js).7z （5个子文件） 
Tools-36MathTools.js 8KB 可视域分析.js 8KB Tools-36EllipseGeometryLibraryEx.js 12KB Tools-36TerrainToolCopy.js 1KB Tools-36PrimitivePoints.js 10KB资源评论
GISMagic2021-06-28跑不起来啊
傲雪寒梅201314992024-07-03运行不了。。。。
小嘉龙。2021-06-04这个文件只是固定的位置添加可视域分析
