MAKING PHYSICS GAMES in HTML5

Before we Start...

SIGN UP AT PLAYCANVAS.COM


MozFest 2013:
Making Physics-based HTML5 Games
in 30 Minutes
Will Eastcott, Co-founder, @willeastcott

Agenda

PlayCanvas Brain Dump
30 minutes

Exercise: Build A Game in 30 Minutes
30 minutes

A brief history of will

1998-2004: Criterion software


Senior Software Engineer: RenderWare
Head of Consultancy

2004-2007: EA


Product Manager: RenderWare Physics

2007-2009: SonY


Consultant: PlayStation Home

2009-2011: Activision

Technical Director for Europe

What is PlayCanvas?




cloud-hosted, collaborative,  3D game engine 
powered by HTML5  

WHY DEVELOP in the cloud?

  • Access your projects from any device
  • Collaborate in realtime with your team
  • Get instant help and feedback
  • Browse and iterate public projects

Terminology

  • Pack - A level or scene.
  • Entity - A thing in your game.
  • Component - Adds behavior to an entity.
  • Attribute - A property of a component.

Exercise 1: Publish your 1st App

Get people playing your games!
(That's the point, right?)

Graphics

  • Ambient, directional, point and spot lights
  • Static and skinned meshes (up to 256 bones)
  • Wireframe rendering
  • Map types: diffuse, specular, emissive, normal
  • Per-pixel fog
  • Skyboxes
  • Full screen effects

Primitives

Basic shapes: box, sphere, cylinder, cone, capsule
Very useful for prototyping
Can make entire games with them:

Models

3D content that you upload to PlayCanvas

Recommendations:
Supply models in FBX format
Ensure textures are embedded in FBX
Ensure no meshes have >65535 vertices

Material Editing

You can edit materials in Designer
Click once to select entity
Click again to select the material on selected mesh

Scripting

  • Add custom behavior to entities
  • JavaScript API

Workflows

2 available options:

  1. Edit scripts on playcanvas.com
  2. Edit scripts on your filesystem
    and sync using Github or Bitbucket

Anatomy of a Script

Debugging Scripts


Debugging Scripts


Take Care in the Script Editor


Collaborative script editing is not yet enabled
If you are working with other coders, be mindful that the most recent save overwrites the previous
TO BE RESOLVED VERY SOON!

Physics

Allows you to quickly create complex and 
realistic behaviour and interactions

From the Classics...

 

...TO the CONTEMPORARY


Rigid BOdy

Idealised representation of a physical object 
in which deformation is ignored

Properties:
  • position and orientation
  • linear and angular velocity
  • mass, friction, restitution


Actions:
  • apply forces and impulses
  • apply torque and torque impulses

Body Types

  • Static
  • Dynamic
  • Kinematic


Let's see each type in action...

Collision Primitives

A body needs to be linked to a collision primitive:

  • Sphere
  • Box
  • Capsule
  • Triangle Mesh


Let's take a look

Contact Detection

Useful for triggering events
e.g. audio, particles

        initialize: function () {
            // When another body comes into contact with this one,
            // call the onCollision function
            this.entity.collision.on('collisionstart', this.onCrash, this);
        },

        onCrash: function (result) {
            this.entity.audiosource.play('crash');
        },      

Trigger Volumes

Entities that have a collision component but no rigidbody component are trigger volumes
    initialize: function () {
        this.entity.collision.on('triggerenter', this.springTrap, this);
    },

    springTrap: function (entity) {
        // If it is the player that has entered the trigger volume,
        // make him fall to his doom!
        if (entity.getName() === 'Player') {
            this.openTrapDoor();
        }    }, 

Let's make A BounCing Ball!

  1. Create a new project called 'ball'
  2. Create a new pack
  3. Create a camera 
  4. Create a static floor
    (components: primitive, collision and rigidbody)
  5. Create a dynamic ball above floor
    (same components as above)
  6. Set ball rigid body type to 'Dynamic'
  7. Set 'Restitution' on floor and ball to 1
  8. Launch!

Ladies and Gentlemen:
The Main Event


Let's make a classic Pong game!


MozFest 2013:
Making Physics-based HTML5 Games
in 30 Minutes
Will Eastcott, Co-founder, @willeastcott

Making Physics-based HTML5 Games in 30 Minutes

By Will Eastcott

Making Physics-based HTML5 Games in 30 Minutes

A quick overview of PlayCanvas with a focus on physics.

  • 2,148