From 1c1340d812e43cbe554a84ae1fd7cbcca0d793d5 Mon Sep 17 00:00:00 2001
From: Thomas FORGIONE <thomas.forgione@gmail.com>
Date: Mon, 21 Nov 2016 12:02:09 +0100
Subject: [PATCH] Initial commit

---
 ModelConverter.js | 175 ++++++++++++++++++++++++++++++++++++++++++++++
 examples/cube.obj |  33 +++++++++
 2 files changed, 208 insertions(+)
 create mode 100644 ModelConverter.js
 create mode 100644 examples/cube.obj

diff --git a/ModelConverter.js b/ModelConverter.js
new file mode 100644
index 0000000..b5b7834
--- /dev/null
+++ b/ModelConverter.js
@@ -0,0 +1,175 @@
+const fs = require('fs');
+
+class Vertex {
+    constructor(x,y,z) {
+        this.x = x;
+        this.y = y;
+        this.z = z;
+    }
+
+    fromArray(arr) {
+        this.x = arr[0];
+        this.y = arr[1];
+        this.z = arr[2];
+        return this;
+    }
+}
+const Normal = Vertex;
+const TexCoord = Vertex;
+
+class Face {
+    constructor(a,b,c,aTex,bTex,cTex,aNorm,bNorm,cNorm,mtl) {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+
+        this.aTex = aTex;
+        this.bTex = bTex;
+        this.cTex = cTex;
+
+        this.aNorm = aNorm;
+        this.bNorm = bNorm;
+        this.cNorm = cNorm;
+
+        this.mtl = mtl;
+    }
+
+    fromArray(arr) {
+        this.a     = arr[0];
+        this.aTex  = arr[1];
+        this.aNorm = arr[2];
+
+        this.b     = arr[3];
+        this.bTex  = arr[4];
+        this.bNorm = arr[5];
+
+        this.c     = arr[6];
+        this.cTex  = arr[7];
+        this.cNorm = arr[8];
+                           ;
+        this.mtl   = arr[9];
+        return this;
+    }
+}
+
+
+class ModelParser {
+
+    constructor() {
+        if (this.constructor === ModelParser) {
+            throw new Error("Can't instanciate abstract class ModelParser");
+        }
+        this.vertices = [];
+        this.normals = [];
+        this.texCoords = [];
+        this.faces = [];
+    }
+
+    addVertex(vertex) {
+        this.vertices.push(vertex);
+    }
+
+    addTexCoord(texCoord) {
+        this.texCoords.push(texCoord);
+    }
+
+    addNormal(normal) {
+        this.normals.push(normal);
+    }
+
+    addFace(face) {
+        this.faces.push(face);
+    }
+
+    parseLine(string) {
+        if (this.constructor === ModelParser) {
+            throw new Error("Can't call abstract method ModelParser.parseLine");
+        }
+    }
+
+    parseFile(path) {
+        fs
+            .readFileSync(path, 'utf-8')
+            .split('\n')
+            // .map((l) => l.slice(0,-1))
+            .map((a) => this.parseLine(a));
+    }
+
+}
+
+class OBJParser extends ModelParser {
+
+    constructor() {
+        super();
+        this.materials = [];
+    }
+
+    parseLine(string) {
+        let split = string.split(' ');
+
+        switch (split.shift()) {
+            case 'usemtl': this.currentMaterial = split[0]; break;
+
+            case 'v':  this.addVertex  (new Vertex().  fromArray(split)); break;
+            case 'vn': this.addNormal  (new Normal().  fromArray(split)); break;
+            case 'vt': this.addTexCoord(new TexCoord().fromArray(split)); break;
+            case 'f':  this.addFace    (new Face()    .fromArray(split.map(s => s.split('/')).reduce((a,b) => a.concat(b), [])));
+
+        }
+    }
+
+}
+
+class Exporter {
+    constructor(model) {
+        this.model = model;
+    }
+}
+
+class OBJExporter extends Exporter {
+    constructor(model) {
+        super(model);
+    }
+
+    toString() {
+        let string = "";
+
+        for (let vertex of this.model.vertices) {
+            string += "n " + [vertex.x, vertex.y, vertex.z].join(' ') + "\n";
+        }
+
+        string += "\n";
+
+        for (let texCoord of this.model.texCoords) {
+            string += "vt " + [texCoord.x, texCoord.y].join(' ') + "\n";
+        }
+
+        string += "\n"
+
+        for (let normal of this.model.normals) {
+            string += "vn " + [normal.x, normal.y, normal.z].join(' ') + "\n";
+        }
+
+        string += "\n";
+
+        for (let face of this.model.faces) {
+            string += "f ";
+            string += ['a', 'b', 'c'].map(a => [face[a], face[a + 'Tex'], face[a + 'Norm']].join('/')).join(' ');
+            string += '\n';
+        }
+
+        return string;
+    }
+}
+
+if (require.main === module) {
+
+    let parser = new OBJParser();
+    parser.parseFile('./examples/cube.obj');
+
+    let exporter = new OBJExporter(parser);
+    let string = exporter.toString();
+
+    console.log(string);
+
+}
diff --git a/examples/cube.obj b/examples/cube.obj
new file mode 100644
index 0000000..214d29f
--- /dev/null
+++ b/examples/cube.obj
@@ -0,0 +1,33 @@
+v -0.500000 -0.500000 0.500000
+v 0.500000 -0.500000 0.500000
+v -0.500000 0.500000 0.500000
+v 0.500000 0.500000 0.500000
+v -0.500000 0.500000 -0.500000
+v 0.500000 0.500000 -0.500000
+v -0.500000 -0.500000 -0.500000
+v 0.500000 -0.500000 -0.500000
+
+vt 0.000000 0.000000
+vt 1.000000 0.000000
+vt 0.000000 1.000000
+vt 1.000000 1.000000
+
+vn 0.000000 0.000000 1.000000
+vn 0.000000 1.000000 0.000000
+vn 0.000000 0.000000 -1.000000
+vn 0.000000 -1.000000 0.000000
+vn 1.000000 0.000000 0.000000
+vn -1.000000 0.000000 0.000000
+
+f 1/1/1 2/2/1 3/3/1
+f 3/3/1 2/2/1 4/4/1
+f 3/1/2 4/2/2 5/3/2
+f 5/3/2 4/2/2 6/4/2
+f 5/4/3 6/3/3 7/2/3
+f 7/2/3 6/3/3 8/1/3
+f 7/1/4 8/2/4 1/3/4
+f 1/3/4 8/2/4 2/4/4
+f 2/1/5 8/2/5 4/3/5
+f 4/3/5 8/2/5 6/4/5
+f 7/1/6 1/2/6 5/3/6
+f 5/3/6 1/2/6 3/4/6