obj2gltf/lib/obj.js
2016-08-08 11:38:54 -04:00

366 lines
13 KiB
JavaScript

"use strict";
var Cesium = require('cesium');
var Promise = require('bluebird');
var byline = require('byline');
var fs = require('fs-extra');
var path = require('path');
var loadImage = require('./image');
var Material = require('./mtl');
var Cartesian3 = Cesium.Cartesian3;
var defined = Cesium.defined;
module.exports = parseObj;
// OBJ regex patterns are from ThreeJS (https://github.com/mrdoob/three.js/blob/master/examples/js/loaders/OBJLoader.js)
function parseObj(objFile, inputPath) {
return getObjInfo(objFile, inputPath)
.then(function(result) {
var info = result.info;
var materials = result.materials;
var images = result.images;
return processObj(objFile, info, materials, images);
});
}
function processObj(objFile, info, materials, images) {
return new Promise(function(resolve) {
// A vertex is specified by indexes into each of the attribute arrays,
// but these indexes may be different. This maps the separate indexes to a single index.
var vertexCache = {};
var vertexCount = 0;
var vertexArray = [];
var positions = [];
var normals = [];
var uvs = [];
var positionMin = [Number.MAX_VALUE, Number.MAX_VALUE, Number.MAX_VALUE];
var positionMax = [-Number.MAX_VALUE, -Number.MAX_VALUE, -Number.MAX_VALUE];
var hasNormals = info.hasNormals;
var hasUVs = info.hasUVs;
var materialGroups = {}; // Map material to index array
var currentIndexArray;
// Switch to the material-specific index array, or create it if it doesn't exist
function useMaterial(material) {
if (!defined(materials[material])) {
useDefaultMaterial();
} else {
currentIndexArray = materialGroups[material];
if (!defined(currentIndexArray)) {
currentIndexArray = [];
materialGroups[material] = currentIndexArray;
}
}
}
function useDefaultMaterial() {
var defaultMaterial = 'czmDefaultMat';
if (!defined(materials[defaultMaterial])) {
materials[defaultMaterial] = Material.getDefault();
}
useMaterial(defaultMaterial);
}
var materialsLength = Object.keys(materials).length;
if (materialsLength === 0) {
useDefaultMaterial();
}
function getOffset(a, data, components) {
var i = parseInt(a);
if (i < 0) {
// Negative vertex indexes reference the vertices immediately above it
return (data.length / components + i) * components;
}
return (i - 1) * components;
}
function createVertex(p, u, n) {
// Positions
var pi = getOffset(p, positions, 3);
var px = positions[pi + 0];
var py = positions[pi + 1];
var pz = positions[pi + 2];
positionMin[0] = Math.min(px, positionMin[0]);
positionMin[1] = Math.min(py, positionMin[1]);
positionMin[2] = Math.min(pz, positionMin[2]);
positionMax[0] = Math.max(px, positionMax[0]);
positionMax[1] = Math.max(py, positionMax[1]);
positionMax[2] = Math.max(pz, positionMax[2]);
vertexArray.push(px, py, pz);
// Normals
if (hasNormals) {
var ni = getOffset(n, normals, 3);
var nx = normals[ni + 0];
var ny = normals[ni + 1];
var nz = normals[ni + 2];
vertexArray.push(nx, ny, nz);
}
// UVs
if (hasUVs) {
if (defined(u)) {
var ui = getOffset(u, uvs, 2);
var ux = uvs[ui + 0];
var uy = uvs[ui + 1];
// Flip y so 0.0 is the bottom of the image
uy = 1.0 - uy;
vertexArray.push(ux, uy);
} else {
// Some objects in the model may not have uvs, fill with 0's for consistency
vertexArray.push(0.0, 0.0);
}
}
}
function addVertex(v, p, u, n) {
var index = vertexCache[v];
if (!defined(index)) {
index = vertexCount++;
vertexCache[v] = index;
createVertex(p, u, n);
}
return index;
}
function addFace(v1, p1, u1, n1, v2, p2, u2, n2, v3, p3, u3, n3, v4, p4, u4, n4) {
var index1 = addVertex(v1, p1, u1, n1);
var index2 = addVertex(v2, p2, u2, n2);
var index3 = addVertex(v3, p3, u3, n3);
currentIndexArray.push(index1);
currentIndexArray.push(index2);
currentIndexArray.push(index3);
// Triangulate if the face is a quad
if (defined(v4)) {
var index4 = addVertex(v4, p4, u4, n4);
currentIndexArray.push(index1);
currentIndexArray.push(index3);
currentIndexArray.push(index4);
}
}
// v float float float
var vertexPattern = /v( +[\d|\.|\+|\-|e|E]+)( +[\d|\.|\+|\-|e|E]+)( +[\d|\.|\+|\-|e|E]+)/;
// vn float float float
var normalPattern = /vn( +[\d|\.|\+|\-|e|E]+)( +[\d|\.|\+|\-|e|E]+)( +[\d|\.|\+|\-|e|E]+)/;
// vt float float
var uvPattern = /vt( +[\d|\.|\+|\-|e|E]+)( +[\d|\.|\+|\-|e|E]+)/;
// f vertex vertex vertex ...
var facePattern1 = /f( +-?\d+)\/?( +-?\d+)\/?( +-?\d+)\/?( +-?\d+)?\/?/;
// f vertex/uv vertex/uv vertex/uv ...
var facePattern2 = /f( +(-?\d+)\/(-?\d+)\/?)( +(-?\d+)\/(-?\d+)\/?)( +(-?\d+)\/(-?\d+)\/?)( +(-?\d+)\/(-?\d+)\/?)?/;
// f vertex/uv/normal vertex/uv/normal vertex/uv/normal ...
var facePattern3 = /f( +(-?\d+)\/(-?\d+)\/(-?\d+))( +(-?\d+)\/(-?\d+)\/(-?\d+))( +(-?\d+)\/(-?\d+)\/(-?\d+))( +(-?\d+)\/(-?\d+)\/(-?\d+))?/;
// f vertex//normal vertex//normal vertex//normal ...
var facePattern4 = /f( +(-?\d+)\/\/(-?\d+))( +(-?\d+)\/\/(-?\d+))( +(-?\d+)\/\/(-?\d+))( +(-?\d+)\/\/(-?\d+))?/;
var stream = byline(fs.createReadStream(objFile, {encoding: 'utf8'}));
stream.on('data', function (line) {
line = line.trim();
var result;
if ((line.length === 0) || (line.charAt(0) === '#')) {
// Don't process empty lines or comments
} else if ((result = vertexPattern.exec(line)) !== null) {
positions.push(
parseFloat(result[1]),
parseFloat(result[2]),
parseFloat(result[3])
);
} else if ((result = normalPattern.exec(line) ) !== null) {
var nx = parseFloat(result[1]);
var ny = parseFloat(result[2]);
var nz = parseFloat(result[3]);
var normal = Cartesian3.normalize(new Cartesian3(nx, ny, nz), new Cartesian3());
normals.push(normal.x, normal.y, normal.z);
} else if ((result = uvPattern.exec(line)) !== null) {
uvs.push(
parseFloat(result[1]),
parseFloat(result[2])
);
} else if ((result = facePattern1.exec(line)) !== null) {
addFace(
result[1], result[1], undefined, undefined,
result[2], result[2], undefined, undefined,
result[3], result[3], undefined, undefined,
result[4], result[4], undefined, undefined
);
} else if ((result = facePattern2.exec(line)) !== null) {
addFace(
result[1], result[2], result[3], undefined,
result[4], result[5], result[6], undefined,
result[7], result[8], result[9], undefined,
result[10], result[11], result[12], undefined
);
} else if ((result = facePattern3.exec(line)) !== null) {
addFace(
result[1], result[2], result[3], result[4],
result[5], result[6], result[7], result[8],
result[9], result[10], result[11], result[12],
result[13], result[14], result[15], result[16]
);
} else if ((result = facePattern4.exec(line)) !== null) {
addFace(
result[1], result[2], undefined, result[3],
result[4], result[5], undefined, result[6],
result[7], result[8], undefined, result[9],
result[10], result[11], undefined, result[12]
);
} else if (/^usemtl /.test(line)) {
var materialName = line.substring(7).trim();
useMaterial(materialName);
}
});
stream.on('end', function () {
resolve({
vertexCount: vertexCount,
vertexArray: vertexArray,
positionMin: positionMin,
positionMax: positionMax,
hasUVs: hasUVs,
hasNormals: hasNormals,
materialGroups: materialGroups,
materials: materials,
images: images
});
});
});
}
function getImages(inputPath, materials) {
// Collect all the image files from the materials
var images = [];
for (var name in materials) {
if (materials.hasOwnProperty(name)) {
var material = materials[name];
if (defined(material.ambientColorMap) && (images.indexOf(material.ambientColorMap) === -1)) {
images.push(material.ambientColorMap);
}
if (defined(material.diffuseColorMap) && (images.indexOf(material.diffuseColorMap) === -1)) {
images.push(material.diffuseColorMap);
}
if (defined(material.emissionColorMap) && (images.indexOf(material.emissionColorMap) === -1)) {
images.push(material.emissionColorMap);
}
if (defined(material.specularColorMap) && (images.indexOf(material.specularColorMap) === -1)) {
images.push(material.specularColorMap);
}
}
}
// Load the image files
var promises = [];
var imagesInfo = {};
var imagesLength = images.length;
for (var i = 0; i < imagesLength; i++) {
var imagePath = images[i];
if (!path.isAbsolute(imagePath)) {
imagePath = path.join(inputPath, imagePath);
}
promises.push(loadImage(imagePath));
}
return Promise.all(promises)
.then(function(imageInfoArray) {
var imageInfoArrayLength = imageInfoArray.length;
for (var j = 0; j < imageInfoArrayLength; j++) {
var image = images[j];
var imageInfo = imageInfoArray[j];
imagesInfo[image] = imageInfo;
}
return imagesInfo;
});
}
function getMaterials(mtlPath, hasMaterialGroups) {
if (hasMaterialGroups && defined(mtlPath)) {
return Material.parse(mtlPath);
}
return {};
}
function getObjInfo(objFile, inputPath) {
var mtlPath;
var materials;
var info;
var hasMaterialGroups = false;
var hasPositions = false;
var hasNormals = false;
var hasUVs = false;
return new Promise(function(resolve, reject) {
var stream = byline(fs.createReadStream(objFile, {encoding: 'utf8'}));
stream.on('data', function (line) {
if (!defined(mtlPath)) {
var mtllibMatches = line.match(/^mtllib.*/gm);
if (mtllibMatches !== null) {
var mtlFile = mtllibMatches[0].substring(7).trim();
mtlPath = mtlFile;
if (!path.isAbsolute(mtlPath)) {
mtlPath = path.join(inputPath, mtlFile);
}
}
}
if (!hasMaterialGroups) {
hasMaterialGroups = /^usemtl/gm.test(line);
}
if (!hasPositions) {
hasPositions = /^v\s/gm.test(line);
}
if (!hasNormals) {
hasNormals = /^vn/gm.test(line);
}
if (!hasUVs) {
hasUVs = /^vt/gm.test(line);
}
});
stream.on('error', function(err) {
reject(err);
});
stream.on('end', function () {
if (!hasPositions) {
reject(new Error('Could not process OBJ file, no positions.'));
}
info = {
hasNormals: hasNormals,
hasUVs: hasUVs
};
resolve();
});
})
.then(function() {
return getMaterials(mtlPath, hasMaterialGroups);
})
.then(function(returnedMaterials) {
materials = returnedMaterials;
return getImages(inputPath, materials);
})
.then(function(images) {
return {
info : info,
materials : materials,
images : images
};
});
}