/*
* 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 TriangleMesh
*/
define([
'../shapes/AbstractMesh',
'../error/ArgumentError',
'../shaders/BasicTextureProgram',
'../geom/BoundingBox',
'../util/Color',
'../util/ImageSource',
'../geom/Location',
'../util/Logger',
'../geom/Matrix',
'../pick/PickedObject',
'../geom/Position',
'../shapes/ShapeAttributes',
'../shapes/SurfacePolygon',
'../geom/Vec2',
'../geom/Vec3',
],
function (AbstractMesh,
ArgumentError,
BasicTextureProgram,
BoundingBox,
Color,
ImageSource,
Location,
Logger,
Matrix,
PickedObject,
Position,
ShapeAttributes,
SurfacePolygon,
Vec2,
Vec3) {
"use strict";
/**
* Constructs a triangle mesh.
* @alias TriangleMesh
* @constructor
* @augments AbstractMesh
* @classdesc Represents a 3D triangle mesh.
* <p>
* Altitudes within the mesh's positions are interpreted according to the mesh's altitude mode, which
* can be one of the following:
* <ul>
* <li>[WorldWind.ABSOLUTE]{@link WorldWind#ABSOLUTE}</li>
* <li>[WorldWind.RELATIVE_TO_GROUND]{@link WorldWind#RELATIVE_TO_GROUND}</li>
* <li>[WorldWind.CLAMP_TO_GROUND]{@link WorldWind#CLAMP_TO_GROUND}</li>
* </ul>
* If the latter, the mesh positions' altitudes are ignored. (If the mesh should be draped onto the
* terrain, you might want to use {@link SurfacePolygon} instead.)
* <p>
* Meshes have separate attributes for normal display and highlighted display. They use the interior and
* outline attributes of {@link ShapeAttributes}. If those attributes identify an image, that image is
* applied to the mesh. Texture coordinates for the image may be specified, but if not specified the full
* image is stretched over the full mesh. If texture coordinates are specified, there must be one texture
* coordinate for each vertex in the mesh.
*
* @param {Position[]} positions An array containing the mesh vertices.
* There must be no more than 65536 positions. Use [split]{@link TriangleMesh#split} to subdivide large meshes
* into smaller ones that fit this limit.
* @param {Number[]} indices An array of integers identifying the positions of each mesh triangle.
* Each sequence of three indices defines one triangle in the mesh. The indices identify the index of the
* position in the associated positions array. The indices for each triangle should be in counter-clockwise
* order to identify the triangles as front-facing.
* @param {ShapeAttributes} attributes The attributes to associate with this mesh. May be null, in which case
* default attributes are associated.
*
* @throws {ArgumentError} If the specified positions array is null, empty or undefined, the number of indices
* is less than 3 or too many positions are specified (limit is 65536).
*/
var TriangleMesh = function (positions, indices, attributes) {
if (!positions) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "constructor", "missingPositions"));
}
if (positions.length < 1) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "constructor", "missingPositions"));
}
// Check for size limit, which is the max number of available indices for a 16-bit unsigned int.
if (positions.length > 65536) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "constructor",
"Too many positions. Must be fewer than 65537. Use TriangleMesh.split to split the shape."));
}
if (!indices) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "constructor",
"Indices array is null or undefined"));
}
if (indices.length < 3) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "constructor", "Too few indices."));
}
AbstractMesh.call(this, attributes);
// Private. Documentation is with the defined property below and the constructor description above.
this._positions = positions;
// Private. Documentation is with the defined property below and the constructor description above.
this._indices = indices;
this.referencePosition = this._positions[0];
};
TriangleMesh.prototype = Object.create(AbstractMesh.prototype);
Object.defineProperties(TriangleMesh.prototype, {
/**
* This mesh's positions.
*
* @type {Position[]}
* @memberof TriangleMesh.prototype
*/
positions: {
get: function () {
return this._positions;
},
set: function (positions) {
if (!positions) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "positions", "missingPositions"));
}
this._positions = positions;
this.referencePosition = this._positions[0];
this.reset();
}
},
/**
* The mesh indices, an array of integers identifying the indexes of each triangle. Each index in this
* array identifies the index of the corresponding position in the [positions]{@link TriangleMesh#positions}
* array. Each group of three indices in this array identifies the positions of one triangle.
*
*
* @type {Number[]}
* @memberof TriangleMesh.prototype
*/
indices: {
get: function () {
return this._indices;
},
set: function (indices) {
if (!indices) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "indices",
"Indices array is null or undefined"));
}
this._indices = indices;
this.meshIndices = null;
this.reset();
}
},
/**
* The mesh outline indices, an array of integers identifying the positions in the outline. Each index in
* this array identifies the index of the corresponding position in the
* [positions]{@link TriangleMesh#positions} array. The collection of these positions forms the outline
* of this mesh. May be null, in which case no outline is drawn.
*
* @type {Number[]}
* @default null
* @memberof TriangleMesh.prototype
*/
outlineIndices: {
get: function () {
return this._outlineIndices;
},
set: function (indices) {
this._outlineIndices = indices;
this.meshOutlineIndices = null;
this.reset();
}
},
/**
* This mesh's texture coordinates if this mesh is textured. A texture coordinate must be
* provided for each mesh position. Each texture coordinate is a {@link Vec2} containing the s and t
* coordinates, in that order. If no texture coordinates are specified then texture is not applied to
* this mesh.
* @type {Vec2[]}
* @default null
* @memberof TriangleMesh.prototype
*/
textureCoordinates: {
get: function () {
return this._textureCoordinates;
},
set: function (coords) {
if (coords && (coords.length != this._positions.length)) {
throw new ArgumentError(
Logger.logMessage(Logger.LEVEL_SEVERE, "TriangleMesh", "textureCoordinates",
"Number of texture coordinates is inconsistent with the currently specified positions."));
}
this._textureCoordinates = coords;
this.reset();
this.texCoords = null;
}
}
});
// Overridden from AbstractShape base class.
TriangleMesh.prototype.createSurfaceShape = function () {
if (this._outlineIndices) {
var boundaries = [];
for (var i = 0; i < this._outlineIndices.length; i++) {
boundaries.push(this._positions[this._outlineIndices[i]]);
}
return new SurfacePolygon(boundaries, null);
} else {
return null;
}
};
// Overridden from AbstractShape base class.
TriangleMesh.prototype.computeMeshPoints = function (dc, currentData) {
var eyeDistSquared = Number.MAX_VALUE,
eyePoint = dc.navigatorState.eyePoint,
meshPoints = new Float32Array(this._positions.length * 3),
pt = new Vec3(0, 0, 0),
k = 0,
pos, dSquared;
for (var i = 0; i < this._positions.length; i++) {
pos = this._positions[i];
dc.surfacePointForMode(pos.latitude, pos.longitude, pos.altitude * this._altitudeScale,
this.altitudeMode, pt);
dSquared = pt.distanceToSquared(eyePoint);
if (dSquared < eyeDistSquared) {
eyeDistSquared = dSquared;
}
pt.subtract(this.currentData.referencePoint);
meshPoints[k++] = pt[0];
meshPoints[k++] = pt[1];
meshPoints[k++] = pt[2];
}
currentData.eyeDistance = Math.sqrt(eyeDistSquared);
return meshPoints;
};
// Overridden from AbstractShape base class.
TriangleMesh.prototype.computeTexCoords = function () {
if (!this._textureCoordinates) {
return null;
} else {
// Capture the texture coordinates to a single array parallel to the mesh points array.
var texCoords = new Float32Array(2 * this._textureCoordinates.length),
k = 0;
for (var i = 0, len = this._textureCoordinates.length; i < len; i++) {
var texCoord = this._textureCoordinates[i];
texCoords[k++] = texCoord[0];
texCoords[k++] = texCoord[1];
}
return texCoords;
}
};
// Overridden from AbstractShape base class.
TriangleMesh.prototype.computeMeshIndices = function () {
var meshIndices = new Uint16Array(this._indices.length);
for (var i = 0, len = this._indices.length; i < len; i++) {
meshIndices[i] = this._indices[i];
}
return meshIndices;
};
// Overridden from AbstractShape base class.
TriangleMesh.prototype.computeOutlineIndices = function () {
if (!this._outlineIndices) {
return null;
} else {
var meshOutlineIndices = new Uint16Array(this._outlineIndices.length);
for (var i = 0; i < this._outlineIndices.length; i++) {
meshOutlineIndices[i] = this._outlineIndices[i];
}
return meshOutlineIndices;
}
};
/**
* Splits a triangle mesh into several meshes, each of which contains fewer than 65536 positions.
* @param {Position[]} positions An array containing the mesh vertices.
* @param {Number[]} indices An array of integers identifying the positions of each mesh triangle.
* Each sequence of three indices defines one triangle in the mesh. The indices identify the index of the
* position in the associated positions array.
* @param {Vec2[]} textureCoords The mesh's texture coordinates.
* @param {Number[]} outlineIndices The mesh's outline indices.
* @returns {Object[]} An array of objects, each of which defines one subdivision of the full mesh. Each object
* in the array has the properties of the same name as the input arguments.
*/
TriangleMesh.split = function (positions, indices, textureCoords, outlineIndices) {
var splitPositions = [],
splitTexCoords = [],
splitIndices = [],
indexMap = [],
result = [],
originalIndex, mappedIndex;
for (var i = 0; i <= indices.length; i++) {
if ((i === indices.length) || ((splitPositions.length > 65533) && splitIndices.length % 3 === 0)) {
if (splitPositions.length > 0) {
var shape = {
positions: splitPositions,
indices: splitIndices
};
if (textureCoords) {
shape.textureCoords = splitTexCoords;
}
if (outlineIndices) {
var splitOutline = [];
for (var j = 0; j < outlineIndices.length; j++) {
originalIndex = outlineIndices[j];
mappedIndex = indexMap[originalIndex];
if (mappedIndex) {
splitOutline.push(indexMap[outlineIndices[j]]);
}
}
shape.outlineIndices = splitOutline;
}
result.push(shape);
}
if (i === indices.length) {
break;
}
splitPositions = [];
splitIndices = [];
indexMap = [];
}
originalIndex = indices[i];
mappedIndex = indexMap[originalIndex];
if (!mappedIndex) {
mappedIndex = splitPositions.length;
indexMap[originalIndex] = mappedIndex;
splitPositions.push(positions[originalIndex]);
if (textureCoords) {
splitTexCoords.push(textureCoords[originalIndex]);
}
}
splitIndices.push(mappedIndex);
}
return result;
};
return TriangleMesh;
});