/*global define*/
define([
'../Core/Cartesian2',
'../Core/Cartesian3',
'../Core/Cartesian4',
'../Core/defined',
'../Core/defineProperties',
'../Core/DeveloperError',
'../Core/Matrix4',
'./CullingVolume'
], function(
Cartesian2,
Cartesian3,
Cartesian4,
defined,
defineProperties,
DeveloperError,
Matrix4,
CullingVolume) {
'use strict';
/**
* The viewing frustum is defined by 6 planes.
* Each plane is represented by a {@link Cartesian4} object, where the x, y, and z components
* define the unit vector normal to the plane, and the w component is the distance of the
* plane from the origin/camera position.
*
* @alias OrthographicFrustum
* @constructor
*
* @example
* var maxRadii = ellipsoid.maximumRadius;
*
* var frustum = new Cesium.OrthographicFrustum();
* frustum.right = maxRadii * Cesium.Math.PI;
* frustum.left = -c.frustum.right;
* frustum.top = c.frustum.right * (canvas.clientHeight / canvas.clientWidth);
* frustum.bottom = -c.frustum.top;
* frustum.near = 0.01 * maxRadii;
* frustum.far = 50.0 * maxRadii;
*/
function OrthographicFrustum() {
/**
* The left clipping plane.
* @type {Number}
* @default undefined
*/
this.left = undefined;
this._left = undefined;
/**
* The right clipping plane.
* @type {Number}
* @default undefined
*/
this.right = undefined;
this._right = undefined;
/**
* The top clipping plane.
* @type {Number}
* @default undefined
*/
this.top = undefined;
this._top = undefined;
/**
* The bottom clipping plane.
* @type {Number}
* @default undefined
*/
this.bottom = undefined;
this._bottom = undefined;
/**
* The distance of the near plane.
* @type {Number}
* @default 1.0
*/
this.near = 1.0;
this._near = this.near;
/**
* The distance of the far plane.
* @type {Number}
* @default 500000000.0;
*/
this.far = 500000000.0;
this._far = this.far;
this._cullingVolume = new CullingVolume();
this._orthographicMatrix = new Matrix4();
}
function update(frustum) {
//>>includeStart('debug', pragmas.debug);
if (!defined(frustum.right) || !defined(frustum.left) ||
!defined(frustum.top) || !defined(frustum.bottom) ||
!defined(frustum.near) || !defined(frustum.far)) {
throw new DeveloperError('right, left, top, bottom, near, or far parameters are not set.');
}
//>>includeEnd('debug');
if (frustum.top !== frustum._top || frustum.bottom !== frustum._bottom ||
frustum.left !== frustum._left || frustum.right !== frustum._right ||
frustum.near !== frustum._near || frustum.far !== frustum._far) {
//>>includeStart('debug', pragmas.debug);
if (frustum.left > frustum.right) {
throw new DeveloperError('right must be greater than left.');
}
if (frustum.bottom > frustum.top) {
throw new DeveloperError('top must be greater than bottom.');
}
if (frustum.near <= 0 || frustum.near > frustum.far) {
throw new DeveloperError('near must be greater than zero and less than far.');
}
//>>includeEnd('debug');
frustum._left = frustum.left;
frustum._right = frustum.right;
frustum._top = frustum.top;
frustum._bottom = frustum.bottom;
frustum._near = frustum.near;
frustum._far = frustum.far;
frustum._orthographicMatrix = Matrix4.computeOrthographicOffCenter(frustum.left, frustum.right, frustum.bottom, frustum.top, frustum.near, frustum.far, frustum._orthographicMatrix);
}
}
defineProperties(OrthographicFrustum.prototype, {
/**
* Gets the orthographic projection matrix computed from the view frustum.
* @memberof OrthographicFrustum.prototype
* @type {Matrix4}
* @readonly
*/
projectionMatrix : {
get : function() {
update(this);
return this._orthographicMatrix;
}
}
});
var getPlanesRight = new Cartesian3();
var getPlanesNearCenter = new Cartesian3();
var getPlanesPoint = new Cartesian3();
var negateScratch = new Cartesian3();
/**
* Creates a culling volume for this frustum.
*
* @param {Cartesian3} position The eye position.
* @param {Cartesian3} direction The view direction.
* @param {Cartesian3} up The up direction.
* @returns {CullingVolume} A culling volume at the given position and orientation.
*
* @example
* // Check if a bounding volume intersects the frustum.
* var cullingVolume = frustum.computeCullingVolume(cameraPosition, cameraDirection, cameraUp);
* var intersect = cullingVolume.computeVisibility(boundingVolume);
*/
OrthographicFrustum.prototype.computeCullingVolume = function(position, direction, up) {
//>>includeStart('debug', pragmas.debug);
if (!defined(position)) {
throw new DeveloperError('position is required.');
}
if (!defined(direction)) {
throw new DeveloperError('direction is required.');
}
if (!defined(up)) {
throw new DeveloperError('up is required.');
}
//>>includeEnd('debug');
var planes = this._cullingVolume.planes;
var t = this.top;
var b = this.bottom;
var r = this.right;
var l = this.left;
var n = this.near;
var f = this.far;
var right = Cartesian3.cross(direction, up, getPlanesRight);
var nearCenter = getPlanesNearCenter;
Cartesian3.multiplyByScalar(direction, n, nearCenter);
Cartesian3.add(position, nearCenter, nearCenter);
var point = getPlanesPoint;
// Left plane
Cartesian3.multiplyByScalar(right, l, point);
Cartesian3.add(nearCenter, point, point);
var plane = planes[0];
if (!defined(plane)) {
plane = planes[0] = new Cartesian4();
}
plane.x = right.x;
plane.y = right.y;
plane.z = right.z;
plane.w = -Cartesian3.dot(right, point);
// Right plane
Cartesian3.multiplyByScalar(right, r, point);
Cartesian3.add(nearCenter, point, point);
plane = planes[1];
if (!defined(plane)) {
plane = planes[1] = new Cartesian4();
}
plane.x = -right.x;
plane.y = -right.y;
plane.z = -right.z;
plane.w = -Cartesian3.dot(Cartesian3.negate(right, negateScratch), point);
// Bottom plane
Cartesian3.multiplyByScalar(up, b, point);
Cartesian3.add(nearCenter, point, point);
plane = planes[2];
if (!defined(plane)) {
plane = planes[2] = new Cartesian4();
}
plane.x = up.x;
plane.y = up.y;
plane.z = up.z;
plane.w = -Cartesian3.dot(up, point);
// Top plane
Cartesian3.multiplyByScalar(up, t, point);
Cartesian3.add(nearCenter, point, point);
plane = planes[3];
if (!defined(plane)) {
plane = planes[3] = new Cartesian4();
}
plane.x = -up.x;
plane.y = -up.y;
plane.z = -up.z;
plane.w = -Cartesian3.dot(Cartesian3.negate(up, negateScratch), point);
// Near plane
plane = planes[4];
if (!defined(plane)) {
plane = planes[4] = new Cartesian4();
}
plane.x = direction.x;
plane.y = direction.y;
plane.z = direction.z;
plane.w = -Cartesian3.dot(direction, nearCenter);
// Far plane
Cartesian3.multiplyByScalar(direction, f, point);
Cartesian3.add(position, point, point);
plane = planes[5];
if (!defined(plane)) {
plane = planes[5] = new Cartesian4();
}
plane.x = -direction.x;
plane.y = -direction.y;
plane.z = -direction.z;
plane.w = -Cartesian3.dot(Cartesian3.negate(direction, negateScratch), point);
return this._cullingVolume;
};
/**
* Returns the pixel's width and height in meters.
*
* @param {Number} drawingBufferWidth The width of the drawing buffer.
* @param {Number} drawingBufferHeight The height of the drawing buffer.
* @param {Number} distance The distance to the near plane in meters.
* @param {Cartesian2} result The object onto which to store the result.
* @returns {Cartesian2} The modified result parameter or a new instance of {@link Cartesian2} with the pixel's width and height in the x and y properties, respectively.
*
* @exception {DeveloperError} drawingBufferWidth must be greater than zero.
* @exception {DeveloperError} drawingBufferHeight must be greater than zero.
*
* @example
* // Example 1
* // Get the width and height of a pixel.
* var pixelSize = camera.frustum.getPixelDimensions(scene.drawingBufferWidth, scene.drawingBufferHeight, 0.0, new Cesium.Cartesian2());
*/
OrthographicFrustum.prototype.getPixelDimensions = function(drawingBufferWidth, drawingBufferHeight, distance, result) {
update(this);
//>>includeStart('debug', pragmas.debug);
if (!defined(drawingBufferWidth) || !defined(drawingBufferHeight)) {
throw new DeveloperError('Both drawingBufferWidth and drawingBufferHeight are required.');
}
if (drawingBufferWidth <= 0) {
throw new DeveloperError('drawingBufferWidth must be greater than zero.');
}
if (drawingBufferHeight <= 0) {
throw new DeveloperError('drawingBufferHeight must be greater than zero.');
}
if (!defined(distance)) {
throw new DeveloperError('distance is required.');
}
if (!defined(result)) {
throw new DeveloperError('A result object is required.');
}
//>>includeEnd('debug');
var frustumWidth = this.right - this.left;
var frustumHeight = this.top - this.bottom;
var pixelWidth = frustumWidth / drawingBufferWidth;
var pixelHeight = frustumHeight / drawingBufferHeight;
result.x = pixelWidth;
result.y = pixelHeight;
return result;
};
/**
* Returns a duplicate of a OrthographicFrustum instance.
*
* @param {OrthographicFrustum} [result] The object onto which to store the result.
* @returns {OrthographicFrustum} The modified result parameter or a new PerspectiveFrustum instance if one was not provided.
*/
OrthographicFrustum.prototype.clone = function(result) {
if (!defined(result)) {
result = new OrthographicFrustum();
}
result.left = this.left;
result.right = this.right;
result.top = this.top;
result.bottom = this.bottom;
result.near = this.near;
result.far = this.far;
// force update of clone to compute matrices
result._left = undefined;
result._right = undefined;
result._top = undefined;
result._bottom = undefined;
result._near = undefined;
result._far = undefined;
return result;
};
/**
* Compares the provided OrthographicFrustum componentwise and returns
* <code>true</code> if they are equal, <code>false</code> otherwise.
*
* @param {OrthographicFrustum} [other] The right hand side OrthographicFrustum.
* @returns {Boolean} <code>true</code> if they are equal, <code>false</code> otherwise.
*/
OrthographicFrustum.prototype.equals = function(other) {
return (defined(other) &&
this.right === other.right &&
this.left === other.left &&
this.top === other.top &&
this.bottom === other.bottom &&
this.near === other.near &&
this.far === other.far);
};
return OrthographicFrustum;
});