829 lines
40 KiB
JavaScript
829 lines
40 KiB
JavaScript
/**
|
|
* Cesium - https://github.com/CesiumGS/cesium
|
|
*
|
|
* Copyright 2011-2020 Cesium Contributors
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Columbus View (Pat. Pend.)
|
|
*
|
|
* Portions licensed separately.
|
|
* See https://github.com/CesiumGS/cesium/blob/master/LICENSE.md for full licensing details.
|
|
*/
|
|
define(['exports', './when-8d13db60', './Check-70bec281', './Math-61ede240', './Cartographic-f2a06374', './Cartesian2-16a61632', './BoundingSphere-d018a565', './ComponentDatatype-5862616f', './AttributeCompression-c177f997'], function (exports, when, Check, _Math, Cartographic, Cartesian2, BoundingSphere, ComponentDatatype, AttributeCompression) { 'use strict';
|
|
|
|
/**
|
|
* Determine whether or not other objects are visible or hidden behind the visible horizon defined by
|
|
* an {@link Ellipsoid} and a camera position. The ellipsoid is assumed to be located at the
|
|
* origin of the coordinate system. This class uses the algorithm described in the
|
|
* {@link https://cesium.com/blog/2013/04/25/Horizon-culling/|Horizon Culling} blog post.
|
|
*
|
|
* @alias EllipsoidalOccluder
|
|
*
|
|
* @param {Ellipsoid} ellipsoid The ellipsoid to use as an occluder.
|
|
* @param {Cartesian3} [cameraPosition] The coordinate of the viewer/camera. If this parameter is not
|
|
* specified, {@link EllipsoidalOccluder#cameraPosition} must be called before
|
|
* testing visibility.
|
|
*
|
|
* @constructor
|
|
*
|
|
* @example
|
|
* // Construct an ellipsoidal occluder with radii 1.0, 1.1, and 0.9.
|
|
* var cameraPosition = new Cesium.Cartesian3(5.0, 6.0, 7.0);
|
|
* var occluderEllipsoid = new Cesium.Ellipsoid(1.0, 1.1, 0.9);
|
|
* var occluder = new Cesium.EllipsoidalOccluder(occluderEllipsoid, cameraPosition);
|
|
*
|
|
* @private
|
|
*/
|
|
function EllipsoidalOccluder(ellipsoid, cameraPosition) {
|
|
//>>includeStart('debug', pragmas.debug);
|
|
Check.Check.typeOf.object('ellipsoid', ellipsoid);
|
|
//>>includeEnd('debug');
|
|
|
|
this._ellipsoid = ellipsoid;
|
|
this._cameraPosition = new Cartographic.Cartesian3();
|
|
this._cameraPositionInScaledSpace = new Cartographic.Cartesian3();
|
|
this._distanceToLimbInScaledSpaceSquared = 0.0;
|
|
|
|
// cameraPosition fills in the above values
|
|
if (when.defined(cameraPosition)) {
|
|
this.cameraPosition = cameraPosition;
|
|
}
|
|
}
|
|
|
|
Object.defineProperties(EllipsoidalOccluder.prototype, {
|
|
/**
|
|
* Gets the occluding ellipsoid.
|
|
* @memberof EllipsoidalOccluder.prototype
|
|
* @type {Ellipsoid}
|
|
*/
|
|
ellipsoid : {
|
|
get: function() {
|
|
return this._ellipsoid;
|
|
}
|
|
},
|
|
/**
|
|
* Gets or sets the position of the camera.
|
|
* @memberof EllipsoidalOccluder.prototype
|
|
* @type {Cartesian3}
|
|
*/
|
|
cameraPosition : {
|
|
get : function() {
|
|
return this._cameraPosition;
|
|
},
|
|
set : function(cameraPosition) {
|
|
// See https://cesium.com/blog/2013/04/25/Horizon-culling/
|
|
var ellipsoid = this._ellipsoid;
|
|
var cv = ellipsoid.transformPositionToScaledSpace(cameraPosition, this._cameraPositionInScaledSpace);
|
|
var vhMagnitudeSquared = Cartographic.Cartesian3.magnitudeSquared(cv) - 1.0;
|
|
|
|
Cartographic.Cartesian3.clone(cameraPosition, this._cameraPosition);
|
|
this._cameraPositionInScaledSpace = cv;
|
|
this._distanceToLimbInScaledSpaceSquared = vhMagnitudeSquared;
|
|
}
|
|
}
|
|
});
|
|
|
|
var scratchCartesian = new Cartographic.Cartesian3();
|
|
|
|
/**
|
|
* Determines whether or not a point, the <code>occludee</code>, is hidden from view by the occluder.
|
|
*
|
|
* @param {Cartesian3} occludee The point to test for visibility.
|
|
* @returns {Boolean} <code>true</code> if the occludee is visible; otherwise <code>false</code>.
|
|
*
|
|
* @example
|
|
* var cameraPosition = new Cesium.Cartesian3(0, 0, 2.5);
|
|
* var ellipsoid = new Cesium.Ellipsoid(1.0, 1.1, 0.9);
|
|
* var occluder = new Cesium.EllipsoidalOccluder(ellipsoid, cameraPosition);
|
|
* var point = new Cesium.Cartesian3(0, -3, -3);
|
|
* occluder.isPointVisible(point); //returns true
|
|
*/
|
|
EllipsoidalOccluder.prototype.isPointVisible = function(occludee) {
|
|
var ellipsoid = this._ellipsoid;
|
|
var occludeeScaledSpacePosition = ellipsoid.transformPositionToScaledSpace(occludee, scratchCartesian);
|
|
return isScaledSpacePointVisible(occludeeScaledSpacePosition, this._cameraPositionInScaledSpace, this._distanceToLimbInScaledSpaceSquared);
|
|
};
|
|
|
|
/**
|
|
* Determines whether or not a point expressed in the ellipsoid scaled space, is hidden from view by the
|
|
* occluder. To transform a Cartesian X, Y, Z position in the coordinate system aligned with the ellipsoid
|
|
* into the scaled space, call {@link Ellipsoid#transformPositionToScaledSpace}.
|
|
*
|
|
* @param {Cartesian3} occludeeScaledSpacePosition The point to test for visibility, represented in the scaled space.
|
|
* @returns {Boolean} <code>true</code> if the occludee is visible; otherwise <code>false</code>.
|
|
*
|
|
* @example
|
|
* var cameraPosition = new Cesium.Cartesian3(0, 0, 2.5);
|
|
* var ellipsoid = new Cesium.Ellipsoid(1.0, 1.1, 0.9);
|
|
* var occluder = new Cesium.EllipsoidalOccluder(ellipsoid, cameraPosition);
|
|
* var point = new Cesium.Cartesian3(0, -3, -3);
|
|
* var scaledSpacePoint = ellipsoid.transformPositionToScaledSpace(point);
|
|
* occluder.isScaledSpacePointVisible(scaledSpacePoint); //returns true
|
|
*/
|
|
EllipsoidalOccluder.prototype.isScaledSpacePointVisible = function(occludeeScaledSpacePosition) {
|
|
return isScaledSpacePointVisible(occludeeScaledSpacePosition, this._cameraPositionInScaledSpace, this._distanceToLimbInScaledSpaceSquared);
|
|
};
|
|
|
|
var scratchCameraPositionInScaledSpaceShrunk = new Cartographic.Cartesian3();
|
|
|
|
/**
|
|
* Similar to {@link EllipsoidalOccluder#isScaledSpacePointVisible} except tests against an
|
|
* ellipsoid that has been shrunk by the minimum height when the minimum height is below
|
|
* the ellipsoid. This is intended to be used with points generated by
|
|
* {@link EllipsoidalOccluder#computeHorizonCullingPointPossiblyUnderEllipsoid} or
|
|
* {@link EllipsoidalOccluder#computeHorizonCullingPointFromVerticesPossiblyUnderEllipsoid}.
|
|
*
|
|
* @param {Cartesian3} occludeeScaledSpacePosition The point to test for visibility, represented in the scaled space of the possibly-shrunk ellipsoid.
|
|
* @returns {Boolean} <code>true</code> if the occludee is visible; otherwise <code>false</code>.
|
|
*/
|
|
EllipsoidalOccluder.prototype.isScaledSpacePointVisiblePossiblyUnderEllipsoid = function(occludeeScaledSpacePosition, minimumHeight) {
|
|
var ellipsoid = this._ellipsoid;
|
|
var vhMagnitudeSquared;
|
|
var cv;
|
|
|
|
if (when.defined(minimumHeight) && minimumHeight < 0.0 && ellipsoid.minimumRadius > -minimumHeight) {
|
|
// This code is similar to the cameraPosition setter, but unrolled for performance because it will be called a lot.
|
|
cv = scratchCameraPositionInScaledSpaceShrunk;
|
|
cv.x = this._cameraPosition.x / (ellipsoid.radii.x + minimumHeight);
|
|
cv.y = this._cameraPosition.y / (ellipsoid.radii.y + minimumHeight);
|
|
cv.z = this._cameraPosition.z / (ellipsoid.radii.z + minimumHeight);
|
|
vhMagnitudeSquared = cv.x * cv.x + cv.y * cv.y + cv.z * cv.z - 1.0;
|
|
} else {
|
|
cv = this._cameraPositionInScaledSpace;
|
|
vhMagnitudeSquared = this._distanceToLimbInScaledSpaceSquared;
|
|
}
|
|
|
|
return isScaledSpacePointVisible(occludeeScaledSpacePosition, cv, vhMagnitudeSquared);
|
|
};
|
|
|
|
/**
|
|
* Computes a point that can be used for horizon culling from a list of positions. If the point is below
|
|
* the horizon, all of the positions are guaranteed to be below the horizon as well. The returned point
|
|
* is expressed in the ellipsoid-scaled space and is suitable for use with
|
|
* {@link EllipsoidalOccluder#isScaledSpacePointVisible}.
|
|
*
|
|
* @param {Cartesian3} directionToPoint The direction that the computed point will lie along.
|
|
* A reasonable direction to use is the direction from the center of the ellipsoid to
|
|
* the center of the bounding sphere computed from the positions. The direction need not
|
|
* be normalized.
|
|
* @param {Cartesian3[]} positions The positions from which to compute the horizon culling point. The positions
|
|
* must be expressed in a reference frame centered at the ellipsoid and aligned with the
|
|
* ellipsoid's axes.
|
|
* @param {Cartesian3} [result] The instance on which to store the result instead of allocating a new instance.
|
|
* @returns {Cartesian3} The computed horizon culling point, expressed in the ellipsoid-scaled space.
|
|
*/
|
|
EllipsoidalOccluder.prototype.computeHorizonCullingPoint = function(directionToPoint, positions, result) {
|
|
return computeHorizonCullingPointFromPositions(this._ellipsoid, directionToPoint, positions, result);
|
|
};
|
|
|
|
var scratchEllipsoidShrunk = Cartesian2.Ellipsoid.clone(Cartesian2.Ellipsoid.UNIT_SPHERE);
|
|
|
|
/**
|
|
* Similar to {@link EllipsoidalOccluder#computeHorizonCullingPoint} except computes the culling
|
|
* point relative to an ellipsoid that has been shrunk by the minimum height when the minimum height is below
|
|
* the ellipsoid. The returned point is expressed in the possibly-shrunk ellipsoid-scaled space and is suitable
|
|
* for use with {@link EllipsoidalOccluder#isScaledSpacePointVisiblePossiblyUnderEllipsoid}.
|
|
*
|
|
* @param {Cartesian3} directionToPoint The direction that the computed point will lie along.
|
|
* A reasonable direction to use is the direction from the center of the ellipsoid to
|
|
* the center of the bounding sphere computed from the positions. The direction need not
|
|
* be normalized.
|
|
* @param {Cartesian3[]} positions The positions from which to compute the horizon culling point. The positions
|
|
* must be expressed in a reference frame centered at the ellipsoid and aligned with the
|
|
* ellipsoid's axes.
|
|
* @param {Number} [minimumHeight] The minimum height of all positions. If this value is undefined, all positions are assumed to be above the ellipsoid.
|
|
* @param {Cartesian3} [result] The instance on which to store the result instead of allocating a new instance.
|
|
* @returns {Cartesian3} The computed horizon culling point, expressed in the possibly-shrunk ellipsoid-scaled space.
|
|
*/
|
|
EllipsoidalOccluder.prototype.computeHorizonCullingPointPossiblyUnderEllipsoid = function(directionToPoint, positions, minimumHeight, result) {
|
|
var possiblyShrunkEllipsoid = getPossiblyShrunkEllipsoid(this._ellipsoid, minimumHeight, scratchEllipsoidShrunk);
|
|
return computeHorizonCullingPointFromPositions(possiblyShrunkEllipsoid, directionToPoint, positions, result);
|
|
};
|
|
/**
|
|
* Computes a point that can be used for horizon culling from a list of positions. If the point is below
|
|
* the horizon, all of the positions are guaranteed to be below the horizon as well. The returned point
|
|
* is expressed in the ellipsoid-scaled space and is suitable for use with
|
|
* {@link EllipsoidalOccluder#isScaledSpacePointVisible}.
|
|
*
|
|
* @param {Cartesian3} directionToPoint The direction that the computed point will lie along.
|
|
* A reasonable direction to use is the direction from the center of the ellipsoid to
|
|
* the center of the bounding sphere computed from the positions. The direction need not
|
|
* be normalized.
|
|
* @param {Number[]} vertices The vertices from which to compute the horizon culling point. The positions
|
|
* must be expressed in a reference frame centered at the ellipsoid and aligned with the
|
|
* ellipsoid's axes.
|
|
* @param {Number} [stride=3]
|
|
* @param {Cartesian3} [center=Cartesian3.ZERO]
|
|
* @param {Cartesian3} [result] The instance on which to store the result instead of allocating a new instance.
|
|
* @returns {Cartesian3} The computed horizon culling point, expressed in the ellipsoid-scaled space.
|
|
*/
|
|
EllipsoidalOccluder.prototype.computeHorizonCullingPointFromVertices = function(directionToPoint, vertices, stride, center, result) {
|
|
return computeHorizonCullingPointFromVertices(this._ellipsoid, directionToPoint, vertices, stride, center, result);
|
|
};
|
|
|
|
/**
|
|
* Similar to {@link EllipsoidalOccluder#computeHorizonCullingPointFromVertices} except computes the culling
|
|
* point relative to an ellipsoid that has been shrunk by the minimum height when the minimum height is below
|
|
* the ellipsoid. The returned point is expressed in the possibly-shrunk ellipsoid-scaled space and is suitable
|
|
* for use with {@link EllipsoidalOccluder#isScaledSpacePointVisiblePossiblyUnderEllipsoid}.
|
|
*
|
|
* @param {Cartesian3} directionToPoint The direction that the computed point will lie along.
|
|
* A reasonable direction to use is the direction from the center of the ellipsoid to
|
|
* the center of the bounding sphere computed from the positions. The direction need not
|
|
* be normalized.
|
|
* @param {Number[]} vertices The vertices from which to compute the horizon culling point. The positions
|
|
* must be expressed in a reference frame centered at the ellipsoid and aligned with the
|
|
* ellipsoid's axes.
|
|
* @param {Number} [stride=3]
|
|
* @param {Cartesian3} [center=Cartesian3.ZERO]
|
|
* @param {Number} [minimumHeight] The minimum height of all vertices. If this value is undefined, all vertices are assumed to be above the ellipsoid.
|
|
* @param {Cartesian3} [result] The instance on which to store the result instead of allocating a new instance.
|
|
* @returns {Cartesian3} The computed horizon culling point, expressed in the possibly-shrunk ellipsoid-scaled space.
|
|
*/
|
|
EllipsoidalOccluder.prototype.computeHorizonCullingPointFromVerticesPossiblyUnderEllipsoid = function(directionToPoint, vertices, stride, center, minimumHeight, result) {
|
|
var possiblyShrunkEllipsoid = getPossiblyShrunkEllipsoid(this._ellipsoid, minimumHeight, scratchEllipsoidShrunk);
|
|
return computeHorizonCullingPointFromVertices(possiblyShrunkEllipsoid, directionToPoint, vertices, stride, center, result);
|
|
};
|
|
|
|
var subsampleScratch = [];
|
|
|
|
/**
|
|
* Computes a point that can be used for horizon culling of a rectangle. If the point is below
|
|
* the horizon, the ellipsoid-conforming rectangle is guaranteed to be below the horizon as well.
|
|
* The returned point is expressed in the ellipsoid-scaled space and is suitable for use with
|
|
* {@link EllipsoidalOccluder#isScaledSpacePointVisible}.
|
|
*
|
|
* @param {Rectangle} rectangle The rectangle for which to compute the horizon culling point.
|
|
* @param {Ellipsoid} ellipsoid The ellipsoid on which the rectangle is defined. This may be different from
|
|
* the ellipsoid used by this instance for occlusion testing.
|
|
* @param {Cartesian3} [result] The instance on which to store the result instead of allocating a new instance.
|
|
* @returns {Cartesian3} The computed horizon culling point, expressed in the ellipsoid-scaled space.
|
|
*/
|
|
EllipsoidalOccluder.prototype.computeHorizonCullingPointFromRectangle = function(rectangle, ellipsoid, result) {
|
|
//>>includeStart('debug', pragmas.debug);
|
|
Check.Check.typeOf.object('rectangle', rectangle);
|
|
//>>includeEnd('debug');
|
|
|
|
var positions = Cartesian2.Rectangle.subsample(rectangle, ellipsoid, 0.0, subsampleScratch);
|
|
var bs = BoundingSphere.BoundingSphere.fromPoints(positions);
|
|
|
|
// If the bounding sphere center is too close to the center of the occluder, it doesn't make
|
|
// sense to try to horizon cull it.
|
|
if (Cartographic.Cartesian3.magnitude(bs.center) < 0.1 * ellipsoid.minimumRadius) {
|
|
return undefined;
|
|
}
|
|
|
|
return this.computeHorizonCullingPoint(bs.center, positions, result);
|
|
};
|
|
|
|
var scratchEllipsoidShrunkRadii = new Cartographic.Cartesian3();
|
|
|
|
function getPossiblyShrunkEllipsoid(ellipsoid, minimumHeight, result) {
|
|
if (when.defined(minimumHeight) && minimumHeight < 0.0 && ellipsoid.minimumRadius > -minimumHeight) {
|
|
var ellipsoidShrunkRadii = Cartographic.Cartesian3.fromElements(
|
|
ellipsoid.radii.x + minimumHeight,
|
|
ellipsoid.radii.y + minimumHeight,
|
|
ellipsoid.radii.z + minimumHeight,
|
|
scratchEllipsoidShrunkRadii
|
|
);
|
|
ellipsoid = Cartesian2.Ellipsoid.fromCartesian3(ellipsoidShrunkRadii, result);
|
|
}
|
|
return ellipsoid;
|
|
}
|
|
|
|
function computeHorizonCullingPointFromPositions(ellipsoid, directionToPoint, positions, result) {
|
|
//>>includeStart('debug', pragmas.debug);
|
|
Check.Check.typeOf.object('directionToPoint', directionToPoint);
|
|
Check.Check.defined('positions', positions);
|
|
//>>includeEnd('debug');
|
|
|
|
if (!when.defined(result)) {
|
|
result = new Cartographic.Cartesian3();
|
|
}
|
|
|
|
var scaledSpaceDirectionToPoint = computeScaledSpaceDirectionToPoint(ellipsoid, directionToPoint);
|
|
var resultMagnitude = 0.0;
|
|
|
|
for (var i = 0, len = positions.length; i < len; ++i) {
|
|
var position = positions[i];
|
|
var candidateMagnitude = computeMagnitude(ellipsoid, position, scaledSpaceDirectionToPoint);
|
|
if (candidateMagnitude < 0.0) {
|
|
// all points should face the same direction, but this one doesn't, so return undefined
|
|
return undefined;
|
|
}
|
|
resultMagnitude = Math.max(resultMagnitude, candidateMagnitude);
|
|
}
|
|
|
|
return magnitudeToPoint(scaledSpaceDirectionToPoint, resultMagnitude, result);
|
|
}
|
|
|
|
var positionScratch = new Cartographic.Cartesian3();
|
|
|
|
function computeHorizonCullingPointFromVertices(ellipsoid, directionToPoint, vertices, stride, center, result) {
|
|
//>>includeStart('debug', pragmas.debug);
|
|
Check.Check.typeOf.object('directionToPoint', directionToPoint);
|
|
Check.Check.defined('vertices', vertices);
|
|
Check.Check.typeOf.number('stride', stride);
|
|
//>>includeEnd('debug');
|
|
|
|
if (!when.defined(result)) {
|
|
result = new Cartographic.Cartesian3();
|
|
}
|
|
|
|
stride = when.defaultValue(stride, 3);
|
|
center = when.defaultValue(center, Cartographic.Cartesian3.ZERO);
|
|
var scaledSpaceDirectionToPoint = computeScaledSpaceDirectionToPoint(ellipsoid, directionToPoint);
|
|
var resultMagnitude = 0.0;
|
|
|
|
for (var i = 0, len = vertices.length; i < len; i += stride) {
|
|
positionScratch.x = vertices[i] + center.x;
|
|
positionScratch.y = vertices[i + 1] + center.y;
|
|
positionScratch.z = vertices[i + 2] + center.z;
|
|
|
|
var candidateMagnitude = computeMagnitude(ellipsoid, positionScratch, scaledSpaceDirectionToPoint);
|
|
if (candidateMagnitude < 0.0) {
|
|
// all points should face the same direction, but this one doesn't, so return undefined
|
|
return undefined;
|
|
}
|
|
resultMagnitude = Math.max(resultMagnitude, candidateMagnitude);
|
|
}
|
|
|
|
return magnitudeToPoint(scaledSpaceDirectionToPoint, resultMagnitude, result);
|
|
}
|
|
|
|
function isScaledSpacePointVisible(occludeeScaledSpacePosition, cameraPositionInScaledSpace, distanceToLimbInScaledSpaceSquared) {
|
|
// See https://cesium.com/blog/2013/04/25/Horizon-culling/
|
|
var cv = cameraPositionInScaledSpace;
|
|
var vhMagnitudeSquared = distanceToLimbInScaledSpaceSquared;
|
|
var vt = Cartographic.Cartesian3.subtract(occludeeScaledSpacePosition, cv, scratchCartesian);
|
|
var vtDotVc = -Cartographic.Cartesian3.dot(vt, cv);
|
|
// If vhMagnitudeSquared < 0 then we are below the surface of the ellipsoid and
|
|
// in this case, set the culling plane to be on V.
|
|
var isOccluded = vhMagnitudeSquared < 0 ? vtDotVc > 0 : (vtDotVc > vhMagnitudeSquared &&
|
|
vtDotVc * vtDotVc / Cartographic.Cartesian3.magnitudeSquared(vt) > vhMagnitudeSquared);
|
|
return !isOccluded;
|
|
}
|
|
|
|
var scaledSpaceScratch = new Cartographic.Cartesian3();
|
|
var directionScratch = new Cartographic.Cartesian3();
|
|
|
|
function computeMagnitude(ellipsoid, position, scaledSpaceDirectionToPoint) {
|
|
var scaledSpacePosition = ellipsoid.transformPositionToScaledSpace(position, scaledSpaceScratch);
|
|
var magnitudeSquared = Cartographic.Cartesian3.magnitudeSquared(scaledSpacePosition);
|
|
var magnitude = Math.sqrt(magnitudeSquared);
|
|
var direction = Cartographic.Cartesian3.divideByScalar(scaledSpacePosition, magnitude, directionScratch);
|
|
|
|
// For the purpose of this computation, points below the ellipsoid are consider to be on it instead.
|
|
magnitudeSquared = Math.max(1.0, magnitudeSquared);
|
|
magnitude = Math.max(1.0, magnitude);
|
|
|
|
var cosAlpha = Cartographic.Cartesian3.dot(direction, scaledSpaceDirectionToPoint);
|
|
var sinAlpha = Cartographic.Cartesian3.magnitude(Cartographic.Cartesian3.cross(direction, scaledSpaceDirectionToPoint, direction));
|
|
var cosBeta = 1.0 / magnitude;
|
|
var sinBeta = Math.sqrt(magnitudeSquared - 1.0) * cosBeta;
|
|
|
|
return 1.0 / (cosAlpha * cosBeta - sinAlpha * sinBeta);
|
|
}
|
|
|
|
function magnitudeToPoint(scaledSpaceDirectionToPoint, resultMagnitude, result) {
|
|
// The horizon culling point is undefined if there were no positions from which to compute it,
|
|
// the directionToPoint is pointing opposite all of the positions, or if we computed NaN or infinity.
|
|
if (resultMagnitude <= 0.0 || resultMagnitude === 1.0 / 0.0 || resultMagnitude !== resultMagnitude) {
|
|
return undefined;
|
|
}
|
|
|
|
return Cartographic.Cartesian3.multiplyByScalar(scaledSpaceDirectionToPoint, resultMagnitude, result);
|
|
}
|
|
|
|
var directionToPointScratch = new Cartographic.Cartesian3();
|
|
|
|
function computeScaledSpaceDirectionToPoint(ellipsoid, directionToPoint) {
|
|
if (Cartographic.Cartesian3.equals(directionToPoint, Cartographic.Cartesian3.ZERO)) {
|
|
return directionToPoint;
|
|
}
|
|
|
|
ellipsoid.transformPositionToScaledSpace(directionToPoint, directionToPointScratch);
|
|
return Cartographic.Cartesian3.normalize(directionToPointScratch, directionToPointScratch);
|
|
}
|
|
|
|
/**
|
|
* This enumerated type is used to determine how the vertices of the terrain mesh are compressed.
|
|
*
|
|
* @exports TerrainQuantization
|
|
*
|
|
* @private
|
|
*/
|
|
var TerrainQuantization = {
|
|
/**
|
|
* The vertices are not compressed.
|
|
*
|
|
* @type {Number}
|
|
* @constant
|
|
*/
|
|
NONE : 0,
|
|
|
|
/**
|
|
* The vertices are compressed to 12 bits.
|
|
*
|
|
* @type {Number}
|
|
* @constant
|
|
*/
|
|
BITS12 : 1
|
|
};
|
|
|
|
var TerrainQuantization$1 = Object.freeze(TerrainQuantization);
|
|
|
|
var cartesian3Scratch = new Cartographic.Cartesian3();
|
|
var cartesian3DimScratch = new Cartographic.Cartesian3();
|
|
var cartesian2Scratch = new Cartesian2.Cartesian2();
|
|
var matrix4Scratch = new BoundingSphere.Matrix4();
|
|
var matrix4Scratch2 = new BoundingSphere.Matrix4();
|
|
|
|
var SHIFT_LEFT_12 = Math.pow(2.0, 12.0);
|
|
|
|
/**
|
|
* Data used to quantize and pack the terrain mesh. The position can be unpacked for picking and all attributes
|
|
* are unpacked in the vertex shader.
|
|
*
|
|
* @alias TerrainEncoding
|
|
* @constructor
|
|
*
|
|
* @param {AxisAlignedBoundingBox} axisAlignedBoundingBox The bounds of the tile in the east-north-up coordinates at the tiles center.
|
|
* @param {Number} minimumHeight The minimum height.
|
|
* @param {Number} maximumHeight The maximum height.
|
|
* @param {Matrix4} fromENU The east-north-up to fixed frame matrix at the center of the terrain mesh.
|
|
* @param {Boolean} hasVertexNormals If the mesh has vertex normals.
|
|
* @param {Boolean} [hasWebMercatorT=false] true if the terrain data includes a Web Mercator texture coordinate; otherwise, false.
|
|
*
|
|
* @private
|
|
*/
|
|
function TerrainEncoding(axisAlignedBoundingBox, minimumHeight, maximumHeight, fromENU, hasVertexNormals, hasWebMercatorT) {
|
|
var quantization = TerrainQuantization$1.NONE;
|
|
var center;
|
|
var toENU;
|
|
var matrix;
|
|
|
|
if (when.defined(axisAlignedBoundingBox) && when.defined(minimumHeight) && when.defined(maximumHeight) && when.defined(fromENU)) {
|
|
var minimum = axisAlignedBoundingBox.minimum;
|
|
var maximum = axisAlignedBoundingBox.maximum;
|
|
|
|
var dimensions = Cartographic.Cartesian3.subtract(maximum, minimum, cartesian3DimScratch);
|
|
var hDim = maximumHeight - minimumHeight;
|
|
var maxDim = Math.max(Cartographic.Cartesian3.maximumComponent(dimensions), hDim);
|
|
|
|
if (maxDim < SHIFT_LEFT_12 - 1.0) {
|
|
quantization = TerrainQuantization$1.BITS12;
|
|
} else {
|
|
quantization = TerrainQuantization$1.NONE;
|
|
}
|
|
|
|
quantization = TerrainQuantization$1.NONE;//防止精度损失，出现地形模型匹配不上，默认不压缩
|
|
|
|
center = axisAlignedBoundingBox.center;
|
|
toENU = BoundingSphere.Matrix4.inverseTransformation(fromENU, new BoundingSphere.Matrix4());
|
|
|
|
var translation = Cartographic.Cartesian3.negate(minimum, cartesian3Scratch);
|
|
BoundingSphere.Matrix4.multiply(BoundingSphere.Matrix4.fromTranslation(translation, matrix4Scratch), toENU, toENU);
|
|
|
|
var scale = cartesian3Scratch;
|
|
scale.x = 1.0 / dimensions.x;
|
|
scale.y = 1.0 / dimensions.y;
|
|
scale.z = 1.0 / dimensions.z;
|
|
BoundingSphere.Matrix4.multiply(BoundingSphere.Matrix4.fromScale(scale, matrix4Scratch), toENU, toENU);
|
|
|
|
matrix = BoundingSphere.Matrix4.clone(fromENU);
|
|
BoundingSphere.Matrix4.setTranslation(matrix, Cartographic.Cartesian3.ZERO, matrix);
|
|
|
|
fromENU = BoundingSphere.Matrix4.clone(fromENU, new BoundingSphere.Matrix4());
|
|
|
|
var translationMatrix = BoundingSphere.Matrix4.fromTranslation(minimum, matrix4Scratch);
|
|
var scaleMatrix = BoundingSphere.Matrix4.fromScale(dimensions, matrix4Scratch2);
|
|
var st = BoundingSphere.Matrix4.multiply(translationMatrix, scaleMatrix,matrix4Scratch);
|
|
|
|
BoundingSphere.Matrix4.multiply(fromENU, st, fromENU);
|
|
BoundingSphere.Matrix4.multiply(matrix, st, matrix);
|
|
}
|
|
|
|
/**
|
|
* How the vertices of the mesh were compressed.
|
|
* @type {TerrainQuantization}
|
|
*/
|
|
this.quantization = quantization;
|
|
|
|
/**
|
|
* The minimum height of the tile including the skirts.
|
|
* @type {Number}
|
|
*/
|
|
this.minimumHeight = minimumHeight;
|
|
|
|
/**
|
|
* The maximum height of the tile.
|
|
* @type {Number}
|
|
*/
|
|
this.maximumHeight = maximumHeight;
|
|
|
|
/**
|
|
* The center of the tile.
|
|
* @type {Cartesian3}
|
|
*/
|
|
this.center = center;
|
|
|
|
/**
|
|
* A matrix that takes a vertex from the tile, transforms it to east-north-up at the center and scales
|
|
* it so each component is in the [0, 1] range.
|
|
* @type {Matrix4}
|
|
*/
|
|
this.toScaledENU = toENU;
|
|
|
|
/**
|
|
* A matrix that restores a vertex transformed with toScaledENU back to the earth fixed reference frame
|
|
* @type {Matrix4}
|
|
*/
|
|
this.fromScaledENU = fromENU;
|
|
|
|
/**
|
|
* The matrix used to decompress the terrain vertices in the shader for RTE rendering.
|
|
* @type {Matrix4}
|
|
*/
|
|
this.matrix = matrix;
|
|
|
|
/**
|
|
* The terrain mesh contains normals.
|
|
* @type {Boolean}
|
|
*/
|
|
this.hasVertexNormals = hasVertexNormals;
|
|
|
|
/**
|
|
* The terrain mesh contains a vertical texture coordinate following the Web Mercator projection.
|
|
* @type {Boolean}
|
|
*/
|
|
this.hasWebMercatorT = when.defaultValue(hasWebMercatorT, false);
|
|
}
|
|
|
|
TerrainEncoding.prototype.encode = function(vertexBuffer, bufferIndex, position, uv, height, normalToPack, webMercatorT) {
|
|
var u = uv.x;
|
|
var v = uv.y;
|
|
|
|
if (this.quantization === TerrainQuantization$1.BITS12) {
|
|
position = BoundingSphere.Matrix4.multiplyByPoint(this.toScaledENU, position, cartesian3Scratch);
|
|
|
|
position.x = _Math.CesiumMath.clamp(position.x, 0.0, 1.0);
|
|
position.y = _Math.CesiumMath.clamp(position.y, 0.0, 1.0);
|
|
position.z = _Math.CesiumMath.clamp(position.z, 0.0, 1.0);
|
|
|
|
var hDim = this.maximumHeight - this.minimumHeight;
|
|
var h = _Math.CesiumMath.clamp((height - this.minimumHeight) / hDim, 0.0, 1.0);
|
|
|
|
Cartesian2.Cartesian2.fromElements(position.x, position.y, cartesian2Scratch);
|
|
var compressed0 = AttributeCompression.AttributeCompression.compressTextureCoordinates(cartesian2Scratch);
|
|
|
|
Cartesian2.Cartesian2.fromElements(position.z, h, cartesian2Scratch);
|
|
var compressed1 = AttributeCompression.AttributeCompression.compressTextureCoordinates(cartesian2Scratch);
|
|
|
|
Cartesian2.Cartesian2.fromElements(u, v, cartesian2Scratch);
|
|
var compressed2 = AttributeCompression.AttributeCompression.compressTextureCoordinates(cartesian2Scratch);
|
|
|
|
vertexBuffer[bufferIndex++] = compressed0;
|
|
vertexBuffer[bufferIndex++] = compressed1;
|
|
vertexBuffer[bufferIndex++] = compressed2;
|
|
|
|
if (this.hasWebMercatorT) {
|
|
Cartesian2.Cartesian2.fromElements(webMercatorT, 0.0, cartesian2Scratch);
|
|
var compressed3 = AttributeCompression.AttributeCompression.compressTextureCoordinates(cartesian2Scratch);
|
|
vertexBuffer[bufferIndex++] = compressed3;
|
|
}
|
|
} else {
|
|
Cartographic.Cartesian3.subtract(position, this.center, cartesian3Scratch);
|
|
|
|
vertexBuffer[bufferIndex++] = cartesian3Scratch.x;
|
|
vertexBuffer[bufferIndex++] = cartesian3Scratch.y;
|
|
vertexBuffer[bufferIndex++] = cartesian3Scratch.z;
|
|
vertexBuffer[bufferIndex++] = height;
|
|
vertexBuffer[bufferIndex++] = u;
|
|
vertexBuffer[bufferIndex++] = v;
|
|
|
|
if (this.hasWebMercatorT) {
|
|
vertexBuffer[bufferIndex++] = webMercatorT;
|
|
}
|
|
}
|
|
|
|
if (this.hasVertexNormals) {
|
|
vertexBuffer[bufferIndex++] = AttributeCompression.AttributeCompression.octPackFloat(normalToPack);
|
|
}
|
|
|
|
return bufferIndex;
|
|
};
|
|
|
|
TerrainEncoding.prototype.decodePosition = function(buffer, index, result) {
|
|
if (!when.defined(result)) {
|
|
result = new Cartographic.Cartesian3();
|
|
}
|
|
|
|
index *= this.getStride();
|
|
|
|
if (this.quantization === TerrainQuantization$1.BITS12) {
|
|
var xy = AttributeCompression.AttributeCompression.decompressTextureCoordinates(buffer[index], cartesian2Scratch);
|
|
result.x = xy.x;
|
|
result.y = xy.y;
|
|
|
|
var zh = AttributeCompression.AttributeCompression.decompressTextureCoordinates(buffer[index + 1], cartesian2Scratch);
|
|
result.z = zh.x;
|
|
|
|
return BoundingSphere.Matrix4.multiplyByPoint(this.fromScaledENU, result, result);
|
|
}
|
|
|
|
result.x = buffer[index];
|
|
result.y = buffer[index + 1];
|
|
result.z = buffer[index + 2];
|
|
return Cartographic.Cartesian3.add(result, this.center, result);
|
|
};
|
|
|
|
TerrainEncoding.prototype.decodeTextureCoordinates = function(buffer, index, result) {
|
|
if (!when.defined(result)) {
|
|
result = new Cartesian2.Cartesian2();
|
|
}
|
|
|
|
index *= this.getStride();
|
|
|
|
if (this.quantization === TerrainQuantization$1.BITS12) {
|
|
return AttributeCompression.AttributeCompression.decompressTextureCoordinates(buffer[index + 2], result);
|
|
}
|
|
|
|
return Cartesian2.Cartesian2.fromElements(buffer[index + 4], buffer[index + 5], result);
|
|
};
|
|
|
|
TerrainEncoding.prototype.decodeHeight = function(buffer, index) {
|
|
index *= this.getStride();
|
|
|
|
if (this.quantization === TerrainQuantization$1.BITS12) {
|
|
var zh = AttributeCompression.AttributeCompression.decompressTextureCoordinates(buffer[index + 1], cartesian2Scratch);
|
|
return zh.y * (this.maximumHeight - this.minimumHeight) + this.minimumHeight;
|
|
}
|
|
|
|
return buffer[index + 3];
|
|
};
|
|
|
|
TerrainEncoding.prototype.decodeWebMercatorT = function(buffer, index) {
|
|
index *= this.getStride();
|
|
|
|
if (this.quantization === TerrainQuantization$1.BITS12) {
|
|
return AttributeCompression.AttributeCompression.decompressTextureCoordinates(buffer[index + 3], cartesian2Scratch).x;
|
|
}
|
|
|
|
return buffer[index + 6];
|
|
};
|
|
|
|
TerrainEncoding.prototype.getOctEncodedNormal = function(buffer, index, result) {
|
|
var stride = this.getStride();
|
|
index = (index + 1) * stride - 1;
|
|
|
|
var temp = buffer[index] / 256.0;
|
|
var x = Math.floor(temp);
|
|
var y = (temp - x) * 256.0;
|
|
|
|
return Cartesian2.Cartesian2.fromElements(x, y, result);
|
|
};
|
|
|
|
TerrainEncoding.prototype.getStride = function() {
|
|
var vertexStride;
|
|
|
|
switch (this.quantization) {
|
|
case TerrainQuantization$1.BITS12:
|
|
vertexStride = 3;
|
|
break;
|
|
default:
|
|
vertexStride = 6;
|
|
}
|
|
|
|
if (this.hasWebMercatorT) {
|
|
++vertexStride;
|
|
}
|
|
|
|
if (this.hasVertexNormals) {
|
|
++vertexStride;
|
|
}
|
|
|
|
return vertexStride;
|
|
};
|
|
|
|
var attributesNone = {
|
|
position3DAndHeight : 0,
|
|
textureCoordAndEncodedNormals : 1
|
|
};
|
|
var attributes = {
|
|
compressed0 : 0,
|
|
compressed1 : 1
|
|
};
|
|
|
|
TerrainEncoding.prototype.getAttributes = function(buffer) {
|
|
var datatype = ComponentDatatype.ComponentDatatype.FLOAT;
|
|
var sizeInBytes = ComponentDatatype.ComponentDatatype.getSizeInBytes(datatype);
|
|
var stride;
|
|
|
|
if (this.quantization === TerrainQuantization$1.NONE) {
|
|
var position3DAndHeightLength = 4;
|
|
var numTexCoordComponents = 2;
|
|
|
|
if (this.hasWebMercatorT) {
|
|
++numTexCoordComponents;
|
|
}
|
|
|
|
if (this.hasVertexNormals) {
|
|
++numTexCoordComponents;
|
|
}
|
|
|
|
stride = (position3DAndHeightLength + numTexCoordComponents) * sizeInBytes;
|
|
|
|
return [{
|
|
index : attributesNone.position3DAndHeight,
|
|
vertexBuffer : buffer,
|
|
componentDatatype : datatype,
|
|
componentsPerAttribute : position3DAndHeightLength,
|
|
offsetInBytes : 0,
|
|
strideInBytes : stride
|
|
}, {
|
|
index : attributesNone.textureCoordAndEncodedNormals,
|
|
vertexBuffer : buffer,
|
|
componentDatatype : datatype,
|
|
componentsPerAttribute : numTexCoordComponents,
|
|
offsetInBytes : position3DAndHeightLength * sizeInBytes,
|
|
strideInBytes : stride
|
|
}];
|
|
}
|
|
|
|
var numCompressed0 = 3;
|
|
var numCompressed1 = 0;
|
|
|
|
if (this.hasWebMercatorT || this.hasVertexNormals) {
|
|
++numCompressed0;
|
|
}
|
|
|
|
if (this.hasWebMercatorT && this.hasVertexNormals) {
|
|
++numCompressed1;
|
|
|
|
stride = (numCompressed0 + numCompressed1) * sizeInBytes;
|
|
|
|
return [{
|
|
index : attributes.compressed0,
|
|
vertexBuffer : buffer,
|
|
componentDatatype : datatype,
|
|
componentsPerAttribute : numCompressed0,
|
|
offsetInBytes : 0,
|
|
strideInBytes : stride
|
|
}, {
|
|
index : attributes.compressed1,
|
|
vertexBuffer : buffer,
|
|
componentDatatype : datatype,
|
|
componentsPerAttribute : numCompressed1,
|
|
offsetInBytes : numCompressed0 * sizeInBytes,
|
|
strideInBytes : stride
|
|
}];
|
|
}
|
|
return [{
|
|
index : attributes.compressed0,
|
|
vertexBuffer : buffer,
|
|
componentDatatype : datatype,
|
|
componentsPerAttribute : numCompressed0
|
|
}];
|
|
};
|
|
|
|
TerrainEncoding.prototype.getAttributeLocations = function() {
|
|
if (this.quantization === TerrainQuantization$1.NONE) {
|
|
return attributesNone;
|
|
}
|
|
return attributes;
|
|
};
|
|
|
|
TerrainEncoding.clone = function(encoding, result) {
|
|
if (!when.defined(result)) {
|
|
result = new TerrainEncoding();
|
|
}
|
|
|
|
result.quantization = encoding.quantization;
|
|
result.minimumHeight = encoding.minimumHeight;
|
|
result.maximumHeight = encoding.maximumHeight;
|
|
result.center = Cartographic.Cartesian3.clone(encoding.center);
|
|
result.toScaledENU = BoundingSphere.Matrix4.clone(encoding.toScaledENU);
|
|
result.fromScaledENU = BoundingSphere.Matrix4.clone(encoding.fromScaledENU);
|
|
result.matrix = BoundingSphere.Matrix4.clone(encoding.matrix);
|
|
result.hasVertexNormals = encoding.hasVertexNormals;
|
|
result.hasWebMercatorT = encoding.hasWebMercatorT;
|
|
return result;
|
|
};
|
|
|
|
exports.EllipsoidalOccluder = EllipsoidalOccluder;
|
|
exports.TerrainEncoding = TerrainEncoding;
|
|
|
|
});
|