cesium
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CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.
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JavaScript
import BoundingSphere from './BoundingSphere.js';
import Cartesian3 from './Cartesian3.js';
import Check from './Check.js';
import ComponentDatatype from './ComponentDatatype.js';
import defaultValue from './defaultValue.js';
import defined from './defined.js';
import Geometry from './Geometry.js';
import GeometryAttribute from './GeometryAttribute.js';
import GeometryAttributes from './GeometryAttributes.js';
import PrimitiveType from './PrimitiveType.js';
import VertexFormat from './VertexFormat.js';
/**
* Describes geometry representing a plane centered at the origin, with a unit width and length.
*
* @alias PlaneGeometry
* @constructor
*
* @param {Object} options Object with the following properties:
* @param {VertexFormat} [options.vertexFormat=VertexFormat.DEFAULT] The vertex attributes to be computed.
*
* @example
* var planeGeometry = new Cesium.PlaneGeometry({
* vertexFormat : Cesium.VertexFormat.POSITION_ONLY
* });
*/
function PlaneGeometry(options) {
options = defaultValue(options, defaultValue.EMPTY_OBJECT);
var vertexFormat = defaultValue(options.vertexFormat, VertexFormat.DEFAULT);
this._vertexFormat = vertexFormat;
this._workerName = 'createPlaneGeometry';
}
/**
* The number of elements used to pack the object into an array.
* @type {Number}
*/
PlaneGeometry.packedLength = VertexFormat.packedLength;
/**
* Stores the provided instance into the provided array.
*
* @param {PlaneGeometry} value The value to pack.
* @param {Number[]} array The array to pack into.
* @param {Number} [startingIndex=0] The index into the array at which to start packing the elements.
*
* @returns {Number[]} The array that was packed into
*/
PlaneGeometry.pack = function(value, array, startingIndex) {
//>>includeStart('debug', pragmas.debug);
Check.typeOf.object('value', value);
Check.defined('array', array);
//>>includeEnd('debug');
startingIndex = defaultValue(startingIndex, 0);
VertexFormat.pack(value._vertexFormat, array, startingIndex);
return array;
};
var scratchVertexFormat = new VertexFormat();
var scratchOptions = {
vertexFormat: scratchVertexFormat
};
/**
* Retrieves an instance from a packed array.
*
* @param {Number[]} array The packed array.
* @param {Number} [startingIndex=0] The starting index of the element to be unpacked.
* @param {PlaneGeometry} [result] The object into which to store the result.
* @returns {PlaneGeometry} The modified result parameter or a new PlaneGeometry instance if one was not provided.
*/
PlaneGeometry.unpack = function(array, startingIndex, result) {
//>>includeStart('debug', pragmas.debug);
Check.defined('array', array);
//>>includeEnd('debug');
startingIndex = defaultValue(startingIndex, 0);
var vertexFormat = VertexFormat.unpack(array, startingIndex, scratchVertexFormat);
if (!defined(result)) {
return new PlaneGeometry(scratchOptions);
}
result._vertexFormat = VertexFormat.clone(vertexFormat, result._vertexFormat);
return result;
};
var min = new Cartesian3(-0.5, -0.5, 0.0);
var max = new Cartesian3( 0.5, 0.5, 0.0);
/**
* Computes the geometric representation of a plane, including its vertices, indices, and a bounding sphere.
*
* @param {PlaneGeometry} planeGeometry A description of the plane.
* @returns {Geometry|undefined} The computed vertices and indices.
*/
PlaneGeometry.createGeometry = function(planeGeometry) {
var vertexFormat = planeGeometry._vertexFormat;
var attributes = new GeometryAttributes();
var indices;
var positions;
if (vertexFormat.position) {
// 4 corner points. Duplicated 3 times each for each incident edge/face.
positions = new Float64Array(4 * 3);
// +z face
positions[0] = min.x;
positions[1] = min.y;
positions[2] = 0.0;
positions[3] = max.x;
positions[4] = min.y;
positions[5] = 0.0;
positions[6] = max.x;
positions[7] = max.y;
positions[8] = 0.0;
positions[9] = min.x;
positions[10] = max.y;
positions[11] = 0.0;
attributes.position = new GeometryAttribute({
componentDatatype : ComponentDatatype.DOUBLE,
componentsPerAttribute : 3,
values : positions
});
if (vertexFormat.normal) {
var normals = new Float32Array(4 * 3);
// +z face
normals[0] = 0.0;
normals[1] = 0.0;
normals[2] = 1.0;
normals[3] = 0.0;
normals[4] = 0.0;
normals[5] = 1.0;
normals[6] = 0.0;
normals[7] = 0.0;
normals[8] = 1.0;
normals[9] = 0.0;
normals[10] = 0.0;
normals[11] = 1.0;
attributes.normal = new GeometryAttribute({
componentDatatype : ComponentDatatype.FLOAT,
componentsPerAttribute : 3,
values : normals
});
}
if (vertexFormat.st) {
var texCoords = new Float32Array(4 * 2);
// +z face
texCoords[0] = 0.0;
texCoords[1] = 0.0;
texCoords[2] = 1.0;
texCoords[3] = 0.0;
texCoords[4] = 1.0;
texCoords[5] = 1.0;
texCoords[6] = 0.0;
texCoords[7] = 1.0;
attributes.st = new GeometryAttribute({
componentDatatype : ComponentDatatype.FLOAT,
componentsPerAttribute : 2,
values : texCoords
});
}
if (vertexFormat.tangent) {
var tangents = new Float32Array(4 * 3);
// +z face
tangents[0] = 1.0;
tangents[1] = 0.0;
tangents[2] = 0.0;
tangents[3] = 1.0;
tangents[4] = 0.0;
tangents[5] = 0.0;
tangents[6] = 1.0;
tangents[7] = 0.0;
tangents[8] = 0.0;
tangents[9] = 1.0;
tangents[10] = 0.0;
tangents[11] = 0.0;
attributes.tangent = new GeometryAttribute({
componentDatatype : ComponentDatatype.FLOAT,
componentsPerAttribute : 3,
values : tangents
});
}
if (vertexFormat.bitangent) {
var bitangents = new Float32Array(4 * 3);
// +z face
bitangents[0] = 0.0;
bitangents[1] = 1.0;
bitangents[2] = 0.0;
bitangents[3] = 0.0;
bitangents[4] = 1.0;
bitangents[5] = 0.0;
bitangents[6] = 0.0;
bitangents[7] = 1.0;
bitangents[8] = 0.0;
bitangents[9] = 0.0;
bitangents[10] = 1.0;
bitangents[11] = 0.0;
attributes.bitangent = new GeometryAttribute({
componentDatatype : ComponentDatatype.FLOAT,
componentsPerAttribute : 3,
values : bitangents
});
}
// 2 triangles
indices = new Uint16Array(2 * 3);
// +z face
indices[0] = 0;
indices[1] = 1;
indices[2] = 2;
indices[3] = 0;
indices[4] = 2;
indices[5] = 3;
}
return new Geometry({
attributes : attributes,
indices : indices,
primitiveType : PrimitiveType.TRIANGLES,
boundingSphere : new BoundingSphere(Cartesian3.ZERO, Math.sqrt(2.0))
});
};
export default PlaneGeometry;