The Isit320 2016 Midterm is a chance for you to show what you have learned so far this quarter. There is no absolute right answer for the midterm. Below I list a set of features. Try to complete as many as you can, but do not be concerned if you do not complete everything. If you need to make choices as to which features to complete, aim to complete the ones on the Priority One list.


These are things that everyone has done already:

  • Create a game with a 3D maze using ThreeJs
  • Create two 2D arrays to define the Maze and the NPCs in the maze
  • Create NPCs represented by a sphere and place them in the maze
  • Access a Couch db Database that stores data on your characters.

As a general rule, if you are relatively new to programming, focus on Priority One goals. If you are an experienced programmer, include at least a few Priority Two items. If you are an experienced developer who has taken lots of courses for me, see if you can complete everything. Those rules are so shaky that I can think of exceptions to all of them, and there aren’t many folks in the class. I guess another metric might look like this:

  • Do the best you can.
  • Work hard but don’t pull an all nighter. If its getting late, just go to bed.
  • Have fun. This is small class, and we are learning a lot. Focus on learning, not on a getting a good grade.
  • Trust me. I want you to succeed.

Priority One

Copy your code from the last assignment into a folder called Week07-Midterm.

  • Make characters disappear when we move past one of them.
  • Display number of “living” and “Dead” NPCs in Game Display (the green area on the left.
  • Display a score based on number of spaces “explored”, that is how many grid squares your have found.
  • End the game when all the spaces are explored.

Priority Two

  • Copy the DataMaster program to Week07-DataMaster
  • In the data master, allow the user to view records in edit controls with arrows to iterate through the game records

Look at the Week03-ExpressRoutes program. There we have two edit controls. Here is the Jade for them:

  input#operatorA(type="text", value=2)
  input#operatorB(type="text", value=3)

In the DataMaster part of the midterm, place at least three edit controls on your main window. When the user selects the hyperlink to read in records from the database, display at least three fields from the first record in the edit controls. We used code like this to read from an edit control:


To insert the number 1 into the the control, do something like this:


Here is one of my game records, though yours may look different than mine:

    "id": "AA",
    "npc_id": 1,
    "npc_name": "Suzie One",
    "description": "NPC AA",
    "color": "#00FFFF",
    "value": 15,
    "question": "Is 2 + 2 equal to 4?",
    "answer": true

Display at least three of the value part of the these key/value pairs. For instance, display the npc_name, description and question.

Now place two buttons on the page. If the user clicks one of the buttons you can see the next record, if she presses the other, you can see the previous record. Check to be sure you aren’t iterating past the beginning and end of the records.

'Minimal iterator picture'

Figure01: The minimal implementation of edit controls and buttons to allow iteration through couch game data. This image shows what happens when the user selects Read One Doc and clicks on the Forward button a few times.

Extra Credit

  • Extra credit: Allow the user to insert or delete a record.
  • Extra Credit: Show what direction the camera is facing on the minimap. (Forward, Left, Right, Back)

Refactor Collisions

We have avoided refactoring, but it is time to at least start down this road. Take your collisionDetection method out of control.js and put it in a file called collisions.js:

  • Block copy and cut collisionDetection
  • Create collisions.js on the client side and paste in your code
  • Use define to provide support for RequireJs
  • Define a Collisions with a constructor object. An example to follow is provided floor.js. Remember to use caps to remind the user to construct the object with new. Remember to export your public method using prototype.
  • Construct the object in the init method for control.js. Call your instance collisions. Give it object scope inside control.js
  • You will also have to make changes to main.js

Though I don’t describe every detail, I’ve outlined here in broad strokes the steps you have to do to create a new module. Make sure you understand the steps, and know how to find this description, as we will do this a lot in the coming weeks.

See also:

NPC Creation

Do the same thing with the addSphere method that you did with collisionDetection.

  • FileName: npcs.js
  • ObjectName: Npcs
  • Make addSphere public and rename it to createNpc
  • Declare size as private variable inside of Npcs

Inside of control.js you probably have a array called npcs which is used to keep track of the spheres you have been creating. Carefully rename this variable to npcList and declare it is a public property of Npcs. You will still reference this property from inside control.js. Check each place where you reference and make sure it is being handled correctly.

In Npcs delcare a private function called getName and a couple public properties.

// When you insert an NPC, put it here.
// When you delete an NPC remove it from this list.
Npcs.prototype.npcList = [];

// Track the coordinates of the NPCs here. Possibly redundant?
Npcs.prototype.npcCoordinates = [];

var baseName = 'npc';

function getName(baseName, x, z) {
    return baseName + '_' + x + '_' + z;

Note that you can use the JavaScript split function to retrieve the X and Z coordinates from this name. That is, you can use split to reverse engineer the getName method. The result of this effort should be X and Z coordinates you passed in when creating the name.

When you create a new NPC, assign it a name property. Your code might look something like this:

sphere.name = getName(baseName, x, z);

We will use this name to help us find a particular sphere.

NPC Detection

Now add a public method to Collisions called npcDetection. Call it from the animate method. When you are done your program should now how to detect a collision with an NPC. Remember, we are not using ray tracing at this point. Instead, just detect if you are on the same grid coordinates as the NPC. For instance, iterate through the npcList, use the name to get the coordinates of the NPC, and compare them to the current position of the mainCharacter. Of they match, then you have a hit.

If you find that you have stumbled on an NPC, then remove it from the npcList and from the scene. To help you do so, add a method to Npcs called removeNpc. It might look a little like this, but it should be a public method of Npcs:

var removeNpc = function(x, z, scene, gridNpc) {
      gridNpc[x][z] = 0;      
      var objectName = getName(baseName, x, z);
      var selectedObject = scene.getObjectByName(objectName);
      var index = this.npcList.indexOf(selectedObject);
      this.npcList.splice(index, 1);

The GridNpc property should point at the NPC 2D 24X24 array that we load to track the location of the NPCs. The idea is that once we have discovered and removed an NPC from the scene, we should also remove it from the grid array.

Call removeNpc from control.js when collisions.npcDetection finds an NPC. Except for the method not being public, the code shown above works for me. It removes the NPC both from the npcList and from the Scene. Remove the NPC from the Scene results in the character disappearing. The character is removed from the board.

At some point you will probably want to create a variable with object scope in control.js called mainCharacter. At minimum mainCharacter should be an object literal with two properties, x and z which track the cameras current position in grid coordinates.

Recall that Grid coordinates are the coordinates of the grid we define in our JSON files. Grid coordinates are different from, but not unrelated to, the game coordinates.)

Turn it in

Put your work in two Git folders located in the root of your repository. Call them Week07-Midterm and Week07-DataMaster. Submit the URL of your repository. Please follow these naming conventions. If, for some reason, you want to use other names, be sure to specify the folders in which you have placed your game and your database code.

Make sure the CouchDb database has your name appended to it: game-data-lastname.

Set the zeroth item in your Couch.js array of addresses to You don’t have to set the index to that number, but do make it the first item in your array. Thank you. (That’s the IP address of my CouchDb server here at home.) Example

var servers = ['', ''];


Take full advantage of $.getJSON:

function showDebug(value) {

$.getJSON('grid000.json', function (grid) {
}).done(function () {
    showDebug('Grid loaded second success');
}).fail(function (jqxhr, textStatus, error) {
    showDebug('Grid loaded error: ' + jqxhr.status + ' ' + textStatus + ' ' + error);
}).always(function () {
    showDebug('Grid loaded complete');

Extra Credit

Add sky.