/*
* Copyright 2015-2017 WorldWind 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.
*/
/**
* @exports Frustum
*/
define([
'../error/ArgumentError',
'../geom/Matrix',
'../geom/Plane',
'../util/Logger'
],
function (ArgumentError,
Matrix,
Plane,
Logger) {
"use strict";
/**
* Constructs a frustum.
* @alias Frustum
* @constructor
* @classdesc Represents a six-sided view frustum in Cartesian coordinates.
* @param {Plane} left The frustum's left plane.
* @param {Plane} right The frustum's right plane.
* @param {Plane} bottom The frustum's bottom plane.
* @param {Plane} top The frustum's top plane.
* @param {Plane} near The frustum's near plane.
* @param {Plane} far The frustum's far plane.
* @throws {ArgumentError} If any specified plane is null or undefined.
*/
var Frustum = function (left, right, bottom, top, near, far) {
if (!left || !right || !bottom || !top || !near || !far) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "Frustum", "constructor", "missingPlane"));
}
// Internal. Intentionally not documented. See property accessors below for public interface.
this._left = left;
this._right = right;
this._bottom = bottom;
this._top = top;
this._near = near;
this._far = far;
// Internal. Intentionally not documented.
this._planes = [this._left, this._right, this._top, this._bottom, this._near, this._far];
};
// These accessors are defined in order to prevent changes that would make the properties inconsistent with the
// planes array.
Object.defineProperties(Frustum.prototype, {
/**
* This frustum's left plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
left: {
get: function() {
return this._left;
}
},
/**
* This frustum's right plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
right: {
get: function() {
return this._right;
}
},
/**
* This frustum's bottom plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
bottom: {
get: function() {
return this._bottom;
}
},
/**
* This frustum's top plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
top: {
get: function() {
return this._top;
}
},
/**
* This frustum's near plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
near: {
get: function() {
return this._near;
}
},
/**
* This frustum's far plane.
* @memberof Frustum.prototype
* @type {Plane}
* @readonly
*/
far: {
get: function() {
return this._far;
}
}
});
/**
* Transforms this frustum by a specified matrix.
* @param {Matrix} matrix The matrix to apply to this frustum.
* @returns {Frustum} This frustum set to its original value multiplied by the specified matrix.
* @throws {ArgumentError} If the specified matrix is null or undefined.
*/
Frustum.prototype.transformByMatrix = function (matrix) {
if (!matrix) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "Frustum", "transformByMatrix", "missingMatrix"));
}
this._left.transformByMatrix(matrix);
this._right.transformByMatrix(matrix);
this._bottom.transformByMatrix(matrix);
this._top.transformByMatrix(matrix);
this._near.transformByMatrix(matrix);
this._far.transformByMatrix(matrix);
return this;
};
/**
* Normalizes the plane vectors of the planes composing this frustum.
* @returns {Frustum} This frustum with its planes normalized.
*/
Frustum.prototype.normalize = function () {
this._left.normalize();
this._right.normalize();
this._bottom.normalize();
this._top.normalize();
this._near.normalize();
this._far.normalize();
return this;
};
/**
* Returns a new frustum with each of its planes 1 meter from the center.
* @returns {Frustum} The new frustum.
*/
Frustum.unitFrustum = function () {
return new Frustum(
new Plane(1, 0, 0, 1), // left
new Plane(-1, 0, 0, 1), // right
new Plane(0, 1, 1, 1), // bottom
new Plane(0, -1, 0, 1), // top
new Plane(0, 0, -1, 1), // near
new Plane(0, 0, 1, 1) // far
);
};
/**
* Extracts a frustum from a projection matrix.
* <p>
* This method assumes that the specified matrix represents a projection matrix. If it does not represent a projection matrix
* the results are undefined.
* <p>
* A projection matrix's view frustum is a Cartesian volume that contains everything visible in a scene displayed
* using that projection matrix.
*
* @param {Matrix} matrix The projection matrix to extract the frustum from.
* @return {Frustum} A new frustum containing the projection matrix's view frustum, in eye coordinates.
* @throws {ArgumentError} If the specified matrix is null or undefined.
*/
Frustum.fromProjectionMatrix = function (matrix) {
if (!matrix) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "Frustum", "fromProjectionMatrix", "missingMatrix"));
}
var x, y, z, w, d, left, right, top, bottom, near, far;
// Left Plane = row 4 + row 1:
x = matrix[12] + matrix[0];
y = matrix[13] + matrix[1];
z = matrix[14] + matrix[2];
w = matrix[15] + matrix[3];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
left = new Plane(x / d, y / d, z / d, w / d);
// Right Plane = row 4 - row 1:
x = matrix[12] - matrix[0];
y = matrix[13] - matrix[1];
z = matrix[14] - matrix[2];
w = matrix[15] - matrix[3];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
right = new Plane(x / d, y / d, z / d, w / d);
// Bottom Plane = row 4 + row 2:
x = matrix[12] + matrix[4];
y = matrix[13] + matrix[5];
z = matrix[14] + matrix[6];
w = matrix[15] + matrix[7];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
bottom = new Plane(x / d, y / d, z / d, w / d);
// Top Plane = row 4 - row 2:
x = matrix[12] - matrix[4];
y = matrix[13] - matrix[5];
z = matrix[14] - matrix[6];
w = matrix[15] - matrix[7];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
top = new Plane(x / d, y / d, z / d, w / d);
// Near Plane = row 4 + row 3:
x = matrix[12] + matrix[8];
y = matrix[13] + matrix[9];
z = matrix[14] + matrix[10];
w = matrix[15] + matrix[11];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
near = new Plane(x / d, y / d, z / d, w / d);
// Far Plane = row 4 - row 3:
x = matrix[12] - matrix[8];
y = matrix[13] - matrix[9];
z = matrix[14] - matrix[10];
w = matrix[15] - matrix[11];
d = Math.sqrt(x * x + y * y + z * z); // for normalizing the coordinates
far = new Plane(x / d, y / d, z / d, w / d);
return new Frustum(left, right, bottom, top, near, far);
};
Frustum.prototype.containsPoint = function (point) {
if (!point) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "Frustum", "containsPoint", "missingPoint"));
}
// See if the point is entirely within the frustum. The dot product of the point with each plane's vector
// provides a distance to each plane. If this distance is less than 0, the point is clipped by that plane and
// neither intersects nor is contained by the space enclosed by this Frustum.
if (this._far.dot(point) <= 0)
return false;
if (this._left.dot(point) <= 0)
return false;
if (this._right.dot(point) <= 0)
return false;
if (this._top.dot(point) <= 0)
return false;
if (this._bottom.dot(point) <= 0)
return false;
if (this._near.dot(point) <= 0)
return false;
return true;
};
/**
* Determines whether a line segment intersects this frustum.
*
* @param {Vec3} pointA One end of the segment.
* @param {Vec3} pointB The other end of the segment.
*
* @return {boolean} <code>true</code> if the segment intersects or is contained in this frustum,
* otherwise <code>false</code>.
*
* @throws {ArgumentError} If either point is null or undefined.
*/
Frustum.prototype.intersectsSegment = function (pointA, pointB) {
if (!pointA || !pointB) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "Frustum", "containsPoint", "missingPoint"));
}
// First do a trivial accept test.
if (this.containsPoint(pointA) || this.containsPoint(pointB))
return true;
if (pointA.equals(pointB))
return false;
for (var i = 0, len = this._planes.length; i < len; i++) {
// See if both points are behind the plane and therefore not in the frustum.
if (this._planes[i].onSameSide(pointA, pointB) < 0)
return false;
// See if the segment intersects the plane.
if (this._planes[i].clip(pointA, pointB) != null)
return true;
}
return false; // segment does not intersect frustum
};
return Frustum;
});