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Tritlo/PlyReader.js

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A reader for PLY files for WebGL. Only reads points and normals, currently.
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PlyReader.js
//PlyReader.js (C) 2014 Matthias Pall Gissurarson.
//Partially based on https://github.com/gnomeby/canvas3D, which has no License.
/*
The MIT License (MIT)
Copyright (c) 2014 Matthias Pall Gissurarson
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
var vec4 = {};
vec4.create = function(vec) {
var dest = new Float32Array(4);
if(vec) {
dest[0] = vec[0];
dest[1] = vec[1];
dest[2] = vec[2];
dest[3] = vec[3];
}
return dest;
};
var point4 = vec4;
function loadFile(file){
var data;
if(typeof window === 'undefined'){
var fs = require("fs");
data = fs.readFileSync(file)+'';
} else {
data = loadFileAJAX(file);
}
return data;
};
// Get a file as a string using AJAX
function loadFileAJAX(name) {
var xhr = new XMLHttpRequest(),
okStatus = document.location.protocol === "file:" ? 0 : 200;
var d = new Date();
//We add the current date to avoid caching of request
//Murder for development
xhr.open('GET', name+"?"+d.toJSON(), false);
xhr.send(null);
return xhr.status == okStatus ? xhr.responseText : null;
};
function point3D(x, y, z)
{
this.x = x;
this.y = y;
this.z = z;
}
function getNormal(p0,p1,p2){
var v1 = new point3D(p2.x - p1.x,
p2.y - p1.y,
p2.z - p1.z);
var v2 = new point3D(p0.x - p1.x,
p0.y - p1.y,
p0.z - p1.z);
var normal = new point3D(v1.y*v2.z-v2.y*v1.z,
v1.z*v2.x-v2.z*v1.x,
v1.x*v2.y-v2.x*v1.y);
var normalLen = Math.sqrt(normal.x*normal.x
+ normal.y*normal.y
+ normal.z*normal.z);
normal.x /= normalLen;
normal.y /= normalLen;
normal.z /= normalLen;
return normal;
}
function getPoints(indices,vertices){
var ps = [];
for(var i = 0; i < indices.length; i ++){
ps.push(new point3D(vertices[indices[i]*3+0],
vertices[indices[i]*3+1],
vertices[indices[i]*3+2]));
}
return ps;
}
var PlyReader =(function(){
var parser = {
//Use: plyReader.parse(data);
//Pre: data is a string of a ply file
//Pos: returns an object with the elements of the plyfile
parse: function(data,callback){
var retval,nl,line;
var hasNormal = false;
// Read header
while(data.length)
{
nl = data.indexOf("\n")+1;
line = data.substr(0,nl-1).trim();
data = data.substr(nl);
retval = line.match(/element (\w+) (\d+)/);
if(retval)
{
if(retval[1] == "vertex") var npoints = parseInt(retval[2]);
if(retval[1] == "face") var npolys = parseInt(retval[2]);
}
if(line == "property float nx") hasNormal = true;
//We ignore all but points and normals, for now.
if(line == "end_header") break;
}
// Read points
var minPoint = new point3D(Infinity, Infinity, Infinity);
var maxPoint = new point3D(-Infinity, -Infinity, -Infinity);
var vertices = [];
var vertexNormals = [];
var vNorms = [];
for (var i = 0; i < npoints; i++)
{
nl = data.indexOf("\n")+1;
line = data.substr(0,nl-1).trim();
data = data.substr(nl);
retval = line.split(" ");
var point = new point3D(parseFloat(retval[0]),
parseFloat(retval[1]),
parseFloat(retval[2]));
vertices.push(point.x, point.y, point.z);
if(hasNormal) vNorms.push(parseFloat(retval[3]),
parseFloat(retval[4]),
parseFloat(retval[5]));
minPoint.x = Math.min(minPoint.x, point.x);
minPoint.y = Math.min(minPoint.y, point.y);
minPoint.z = Math.min(minPoint.z, point.z);
maxPoint.x = Math.max(maxPoint.x, point.x);
maxPoint.y = Math.max(maxPoint.y, point.y);
maxPoint.z = Math.max(maxPoint.z, point.z);
}
// Polygons
var pols = [];
var newVertices = [];
for (var i = 0; i < npolys; i++)
{
nl = data.indexOf("\n")+1;
line = data.substr(0,nl-1).trim();
data = data.substr(nl);
retval = line.split(" ");
var nvertex = parseInt(retval[0]);
var indices = [];
for(var j = 0; j < nvertex; j++)
indices.push(parseInt(retval[j+1]));
// Polygon normal
var ps = getPoints(indices,vertices);
if(!hasNormal)
{
var normal = getNormal(ps[0],ps[1],ps[2]);
var ns = [normal,normal,normal];
} else {
var ns = getPoints(indices,vNorms);
}
pols.push(indices);
for(var j = 0; j < 3; j++){
newVertices.push(ps[j].x, ps[j].y, ps[j].z);
vertexNormals.push(ns[j].x, ns[j].y, ns[j].z);
}
//If faces are declared as boxes,
//not triangles.
if (nvertex == 4){
ps.splice(1,1);
if(!hasNormal)
{
var normal = getNormal(ps[0],ps[1],ps[2]);
var ns = [normal,normal,normal,normal];
}
ns.splice(1,1);
for(var j = 0; j < 3; j++){
newVertices.push(ps[j].x, ps[j].y, ps[j].z);
vertexNormals.push(ns[j].x, ns[j].y, ns[j].z);
}
}
}
vertices = newVertices;
// Move to center of object
var centerMove = new point3D(-(maxPoint.x + minPoint.x)/2,
-(maxPoint.y + minPoint.y)/2,
-(maxPoint.z + minPoint.z)/2);
var scaleY = (maxPoint.y - minPoint.y) / 2;
var points = [];
var normals = [];
for (var i = 0; i < vertices.length; i+=3)
{
vertices[i+0] += centerMove.x;
vertices[i+1] += centerMove.y;
vertices[i+2] += centerMove.z;
vertices[i+0] /= scaleY;
vertices[i+1] /= scaleY;
vertices[i+2] /= scaleY;
points.push(point4.create([vertices[i],
vertices[i+1],
vertices[i+2],
1]));
normals.push(point4.create([vertexNormals[i],
vertexNormals[i+1],
vertexNormals[i+2],
0]));
};
return {"points": points, "normals":normals, "polys": pols};
},
getData: function(file){
var data = loadFile(file);
var parsed = this.parse(data);
return parsed;
},
//works both in node.js and on web.
read: function(file){
return this.getData(file);
}
};
Parser = function() {};
Parser.prototype = parser;
parser.Parser = Parser;
return new Parser;
});
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