objConverter.js

This is a Node.js program designed to create a file that holds obj data that can be read by javascript intended to be used with webGL. To start with, I modified this obj converter and made it for Node.js.

What is this repository for?

I created this for CS 559 Computer Graphics at UW - Madison as a way to help me auto create a file of obj data. The output format is based off of this tool.

How do I get set up?

• You must have Node.js downloaded onto your computer in order for this program to run.
• Either copy or download objConverter.js and run using Node.js.
• Save a copy of this program in the directory of your textures and run via the terminal:

node objConverter.js

or

node objConverter.js filename1.obj filename2.obj ...

• The new file will be called:
  • original file: filename.obj

filename.objjs

How to use filename.objjs in your program?

• In html file:

<script src="objFolder/filename.objjs"></script>

• In the object part of your code:
  • Note: This has only been tested with twgl.js but may still work for normal WebGL.

var myVert = LoadedOBJFiles["filename.obj"].groups["myGroup"].webGL.vertices, 
        myNorm = LoadedOBJFiles["filename.obj"].groups["myGroup"].webGL.normals, 
        myTex = LoadedOBJFiles["falconPoly.obj"].groups["myGroup"].webGL.texCoords;

var arrays = {
                	vpos : { numComponents: 3, data: myVert },
                	vtex : {numComponents: 2, data: myTex},
                	vnormal : {numComponents:3, data: myNorm}
            	};

var buffers = twgl.createBufferInfoFromArrays(gl,arrays);

...more code for making objects...

Notes:

• If the normal is not supplied in the obj file, this program will create its own using the vector position data.
  • This is a basic calculation that can be changed if it does not fit your needs. See the calcNormal function.
• The group names for each object is included in the output of the Node.js program so you do not need to look inside the output file.
• This converter will work with any face shape (ex. triangles, quad, poly)

Contribution guidelines

• If you would like to make edits, please create a pull request or make an new issue.

Who do I talk to?

• Andrew Tomko
• tomand285@gmail.com