iPhone Development with Corona SDK

transcript

iPhone Development

with CORONA SDKFriday, April 16, 2010

April 13, 2010

Tuesday 4:00 pm - 5:20 pm

Evan Kirchhoff & Scott Janousek

Friday, April 16, 2010

Agenda

SCOTT JANOUSEK (Hooken Mobile)

Overview of Corona SDK, iPhone/iPad speci!cs, nuts & bolts

EVAN KIRCHHOFF (Ansca Mobile)

Game Dev & the new Corona Physics Engine

Q & AThe part almost everyone likes ...

Evan Kirchhoff

Senior Software Engineer, Ansca Mobile

Legacy Flash Developer (10+ years)

Loves Physics Engines

Scott JanousekBoston, MA, USA

10+ year Flash Veteran

4 years Mobile & Devices Dev

Mobile & Device PlatformsiPhone/iPad, Android, Symbian, Maemo, & many more

I like the a lot of the ideas behind Corona

Scott’s Types of Projects *

* Not-Corona, but no reason why future ports can’t happen. :)

Co-authored Flash Books

Foundation Flash for Mobile Devices

www.flashmobilebook.com

AdvancED Flash on Devices: Mobile Development with Flash Lite and Flash 10

advancED.flashmobilebook.com

First impressions to Corona SDK

“I can’t believe how short a time it took to get up to speed developing mobile apps with Corona.

It’s one of the better emerging mobile development kits I’ve used recently ... pretty cool stuff.”

- Scott Janousek

Prototype (using Corona)

My Contact Info

SCOTT JANOUSEK

@scottjanousek

scott@scottjanousek.com

corona.scottjanousek.com

www.hookenmobile.com

Getting Started

What is Corona?

An SDK that allows developers to write mobile and device apps for various platforms, quickly, and easily.

Corona is made by Ansca Mobile:

www.anscamobile.com

Build Once, Deploy to Many

Android Apple (iPhone/iPad)

Corona SDK on a Mac

Apps Corona is good at:

2-D Games

Graphical-oriented Utilities

Adware & Branded Apps

Rapid Prototyping

Content we’ll talk about today

Prototype, avoid asteroids type game Game with physics engine

Where to download the SDK`

Registration$20 off Corona registration

COUPON CODE360idev2010

Corona installation folder

What’s in the Corona SDK

SDK Documentation

Sample Code

Opening Corona projects

Projects are kept separate folders

Assets are compiled into app

App Code starts in "le “main.lua”

Code Editors :

Text Wrangler, BBEdit, Coda, XCode ...

Corona Development Environment

SIMULATOR

SIMULATOR - iPhone

SIMULATOR - iPad

Debugger

Corona Work"owDesign app in any Graphics Editor

Develop (lua) code in any text editor

Load code into Corona Simulator

Test your app with Sim

Compile App via XCode

Deploy

Lua Basics

First experiences with Lua

Whoa, what language?

Wow, Documentation? Awesome! :)

LOTS of sample code? Fantastic!

Also, many “syntax books” on lua

Hello World with Corona

Lua Programming

Variables

Tables

Functions

Events

... more

Variables in Lua

Tables in Lua

Code Comments in Lua

Buttons in Lua

The Lua Language “Bible”

Lua Books

Code Editor to use

BBEdit

and anything else ...

Game PrototypeWalkthrough

Prototype (using Corona)

My First (Simple) Game

Simple 2D game

Only few hours into this project

I am not done yet (prototype)

I like the immediate results!

Designing the Game

Adobe Fireworks

(Prototyping)

Adobe Photoshop

(Production)

Developing the Game

Populating the StarField

Animating Player/Asteriods

Game Assets

Main Game Loop

Moving the Ship

Collision Detection

Lua Game Framework

ui.lua - for buttons & labels

sprite.lua - for animations

Testing the Game

File->Relaunch

You will useCommand-R

A LOT with Corona

Debugging the Game

Deploying the Game

Game still under development

Not yet on the Apple App Store

Excited about other Platforms (e.g. Android) with Corona

Lessons Learned along way

Keep it simple

Experiment with Sample Lua Code

Visit Ansca Mobile Forum Developer

Read Lua Books & Corona Docs

Things I like about Corona ...Toolset is easy to use

Lua is a simple language to learn

Multiple target devices

API keeps expanding

Physics and other Frameworks TBD

The closeknit support

Corona 2D Physics Engine

Integrates Box2D C++ libraries

(as in Rolando & Crayon Physics)

...but with a much simpler API

Not yet in beta!

Rigid-body physics model

Continuous collision detection

Contact, friction and restitution

Joints, motors, pulleys, ragdoll, etc.

Invisible Collision Geometry

Box2D: the C++ API

(...)Friday, April 16, 2010

Box2D: the C++ API (...)

-0.52 1.44 2.78-0.54 1.42 2.80-0.56 1.41 2.81-0.58 1.39 2.83-0.60 1.36 2.84-0.62 1.34 2.86-0.64 1.31 2.87-0.66 1.28 2.89-0.68 1.25 2.90-0.70 1.21 2.92-0.72 1.17 2.93-0.75 1.16 2.97-0.77 1.14 3.00-0.80 1.13 3.04-0.83 1.11 3.07-0.86 1.08 3.11-0.88 1.06 3.15-0.91 1.03 3.18-0.93 1.04 3.17-0.94 1.06 3.15-0.96 1.07 3.13-0.97 1.08 3.12-0.99 1.09 3.10-1.00 1.09 3.09-1.02 1.09 3.07-1.03 1.09 3.05-1.05 1.09 3.04-1.06 1.09 3.04-1.07 1.09 3.05-1.09 1.09 3.06-1.10 1.09 3.06-1.11 1.08 3.07-1.12 1.08 3.07-1.14 1.06 3.08-1.15 1.05 3.09-1.16 1.04 3.10-1.17 1.03 3.11-1.19 1.01 3.13-1.20 1.00 3.14-1.21 1.00 3.13-1.22 1.01 3.13-1.22 1.02 3.12-1.23 1.02 3.12-1.24 1.02 3.12-1.24 1.02 3.12-1.25 1.02 3.12-1.25 1.02 3.12-1.26 1.01 3.13-1.26 1.00 3.14-1.27 0.99 3.14-1.27 1.00 3.14-1.27 1.00 3.14

What does this example do?(Not that much, yet)

(printf is a poor renderer)

What else does it need?// (OpenGL-ES setup code removed for clarity)

// Draw "myImage.jpg"NSString *path = [[NSBundle mainBundle] pathForResource:@"myImage" ofType:@"jpg"];NSData *texData = [[NSData alloc] initWithContentsOfFile:path];UIImage *image = [[UIImage alloc] initWithData:texData];if (image == nil) NSLog(@"Do real error checking here");

GLuint width = CGImageGetWidth(image.CGImage);GLuint height = CGImageGetHeight(image.CGImage);CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();void *imageData = malloc( height * width * 4 );CGContextRef context = CGBitmapContextCreate( imageData, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big );CGColorSpaceRelease( colorSpace );CGRect imageRect = CGRectMake( 0, 0, width, height );CGContextClearRect( context, imageRect );CGContextTranslateCTM( context, 0, height - height );CGContextDrawImage( context, imageRect, image.CGImage );

glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageData);

CGContextRelease(context);

free(imageData);[image release];[texData release];

(etc.)

The equivalent Corona demo

local physics = require("physics")

physics.start()

local grass = display.newImage("grass.png")grass.x = 160; grass.y = 460

physics.newSimpleBody( grass, { density=0, friction=0.5, bounce=0.5 } )

local crate = display.newImage("crate.png")crate.x = 175; crate.y = -90;

physics.newSimpleBody( crate, { density=1.2, friction=0.5, bounce=0.4 } )

What does this example do?

Creating a Physics Game in Five Minutes

1. Setup

2. Background graphics

3. Ground (physical)

4. Ramp (physical)(You’d also want to add a handful of sprites for the castle, etc.)

4. Ramp (physical)

5. Place eggs (animated)

6. Score display

7. Boulder (and Camera)

8. Collision detection and scoring

9. Play game!

Wrap Up

developer.anscamobile.com

lua.org

corona.scottjanousek.com

Thanks for listening.

What are your questions?

April 13, 2010

Tuesday 4:00 pm - 5:20 pm

Evan & Scott

iPhone Development with Corona SDK

Technology