Archive for the 'Actionscript' Category

26
Feb
12

Games for Kids: Flash vs HTML5 – Presentation Content

Here are the notes for the content of my FITC Amsterdam 2012 presentation Games for Kids: Flash vs HTML5. There are links here to some of the demos, notes and references.

I set myself the objective of learning best practice in game design using HTML5. To best discover all of the foibles and dark corners of this new technology I set myself the constraint of using NO libraries. I wanted to build a game that would work across many devices, and exhibit some sophistication. The presentation details the discoveries made on this journey, showing how I’ve optimised the game engines – and some of the hacks that I’ve felt necessary to apply.

Demo Panel for Session - Click through

While experimenting with HTML5 touch I found some Android devices had a terrible response. It took me a while to realise that it was my display method, Canvas, that caused the poor performance. Moving to displaying with DOM gave me a workable response on most devices.

Multi-touch Ball Physics

A first quick attempt at gameplay interaction was to build a simple ball physics engine. This gives many options in game design and allows for good utilisation of the major strength of mobile devices: touch input. Getting this to work across multiple devices and operating systems gave me confidence that I could achieve a consistency of performance.

Eggy Eggy Pig - visual design by Eloisa(9) & Lola(7)

With the help of my daughters, I set about designing and building a platform game. Eggy Eggy Pig. The requirement was for platforms and surfaces that could run at any angle, as well as spritesheet animations, triggered interactions, collectables and parallax scrolling. Of course control method was key too.

Optical Flow with Lucas Kanade (Flash)

After looking what can be done with HTML5, it is important to understand what can’t be done. Any game project should start with the question ‘what is the appropriate technology to achieve our objectives?’. In many cases the answer will not be HTML5. I show a couple of cases where Flash could be the only solution, including a look at Maestro Flash – a production implementation of the Lucas Kanade optical flow method.

References:

21
Feb
12

Games for Kids. Flash vs HTML5

For my session at FITC Amsterdam 2012 I’ll be talking about making games for kids.

More and more, mobile devices are allowing people to visit our websites away from the desktop. The sites that I work on chiefly consist of games (Flash) and video content (delivered via Flash). This means that mobile devices without Flash will only be able to gain access to a very small amount of content. To improve this situation we are looking at broadening our game content to include HTML5 builds.

HTML5 has a great deal of promise, and in the future we will be able to achieve amazing things within the browser. But what about now? What can be achieved on the current crop of those mobiles and tablets that are available to children?

To explore the development of HTML5 games, I set myself the task of building whole game prototypes with NO libraries. Here, I felt the best way for me to discover and analyse the issues was to code raw.

With a target of mobile and tablet devices I figured that I’d need to hand-roll my own highly performant physics systems, and I wanted this to be fairly sophisticated. I will describe my methods with code and visual examples.

Throughout the session I’ll detail my discoveries. What are the most optimal ways to achieve cross (mobile) browser game builds? How do you achieve high performance on low spec devices? How do you optimise assets? What tools are good to use?

I’ll look at what we can and can’t do with HTML5 – some of the exciting possibilities and some of the game related (currently)missing features.

Also, what next for the mobile technology and gaming? HTML%, Apps or the cloud?

I’ll be posting the session content – game prototypes and performance tests – here on the GameLab before my FITC Amsterdam session.

05
Mar
11

Introduction to Mercator Projections, Latitude and Longitude

Or how to place a map coordinate into 3D space. This post is a brief walk through of the basics from my 2010 presentation “Where in the world? Intercontinental Ballistic Flash”.

Belgian, Flemish geographer and cartographer Gerardus Mercator, in 1569 presented a cylindrical map projection. The Mercator Projection quickly became the standard map used for nautical purposes. It’s advantages were that the scale is linear in any direction around a point, meaning all angles were preserved (conformal).

Geographer and cartographer Gerardus Mercator

Gerardus Mercator

Around the equator feature shapes are accurately portrayed but as the poles are approached there is a size and shape distortion. The scale increases as the pole is neared, eventually becoming infinite when the pole is reached.

If you imagine the world as a beach ball. The Mercator Projection is the equivalent of cutting open the ball at each pole and stretching the skin to form a cylinder. Now slice down the cylinder and you have the map.

The first Mercator projected map. 1569.

All map projections distort the shape or size of the Earth’s (or for that matter any other planet’s) surface. The Mercator Projection exaggerates areas far from the equator. Greenland seems as large as Africa, but is in fact 1/14 of the size, Antartica appears to be the largest continent but is in fact only 5th in terms of area.

Despite the obvious distortions, the Mercator Projection makes a great interactive map. Thanks to the conformality it can be zoomed nearly seamlessly.

So here we have a system that converts a 3D scene, the real world, onto a 2D plane, the map. This system can just as easily convert the 2D back to 3D. It is a coordinate system that requires two positional parameters and one constant: the planet radius.

The positional parameters are latitude and longitude. As developers we are used to standard coordinates x and y. Across then up. Horizontal then vertical. With latitude and longitude we have to think differently. Latitude is vertical and longitude is across. Up then across. Latitudes run from pole to pole, while longitudes run around the planet.

There are 180 degrees of latitude from the South Pole to the North pole, and 360 degrees around the planet. Imagine yourself sat at the centre of the Earth with a laser pointer. Point at the Equator then you are at 0 degrees latitude, at the South Pole -90 degrees and at the North Pole 90 degrees. Now point at the Equator again you can turn 180 degrees around the equator to the right (-180 degrees longitude) and to the left (180 degrees longitude).

With these any point on the surface of the planet can be recorded or indeed any position on a map.

So we have a system for calculating a position on the surface of a sphere, a 3D coordinate, but how do we convert latitude, longitude and the planet’s radius into a 3D x,y,z coordinate?

public static function convertLatLonTo3DPos(lat:Number, lon:Number, radius:Number):Vector3D
{
var v3d:Vector3D = new Vector3D();

//Convert Lat Lon Degrees to Radians
var latRadians:Number = lat * TO_RADIANS;
var lonRadians:Number = lon * TO_RADIANS;

v3d.x = radius * Math.cos(lonRadians) * Math.sin(latRadians);
v3d.z = radius * Math.sin(lonRadians) * Math.sin(latRadians);
v3d.y = -radius * Math.cos(latRadians);

return v3d
}

Here the latitude and longitude are converted into radians ( TO_RADIANS:Number = Math.PI / 180 ). Then the trigonomic functions are applied to the planet radius to return a vector3D x,y and z.

23
Sep
10

Where in the World? Intercontinental Ballistic Flash

I shall be presenting “Where in the World? Intercontinental Ballistic Flash” at Europe’s premier rich media conference Flash on the Beach. I’m scheduled to present in the Pavillion Theatre at 10.15am on Tuesday 28th September.

In the first half of the session I’m going to look at techniques for how to build a world in 3D. Take a 2D map, convert it to 3D. Add some models, information pins, zoomability. I’ll describe some optimisation tricks and tips, and some easy methods to build maths formulae.

In the second half I shall be demonstrating a number of ways to create usable, configurable and fun game components. These include bitmapData constructions and manipulations, delta tweening, model parsing and combinations of all three.

If you are at FOTB 2010 if will be great to see you at my session, if not I shall be posting some of the demos and source here very soon.

Flash on the Beach, Brighton 26th to 29th Septhember 2010

Flash on the Beach

14
Sep
10

My Flash on the Beach 2010 Schedule

The awesome Flash on the Beach conference takes place in Brighton on 26th to the 29th September.
I shall be presenting “Where in the World? Intercontinental Ballistic Flash” on Tuesday morning (10am) – I’ll list more details about it here very soon.

Here is a Twitter list of all the FOTB presenters

These are the sessions I’ll be attending:

Monday
Keynote
Conrad Winchester: ROBOTLEGS AND SIGNALS – A MATCH MADE IN HEAVEN?
Andre Michelle: PULSATILE CRACKLE
Mario Klingemann: SO LONG, AND THANKS FOR ALL THE FLASH
Stacey Mulcahy: DEVELOPING FOR THE SOCIAL MEDIA DOUCHEBAG – AN INTRO TO SOCIAL API’S
Robert Hodgin: PRACTICE MAKES PERFECT, SO WHAT ARE YOU PRACTICING?
Stefan Sagmeister: DESIGN AND HAPPINESS

Tuesday:
THE ELEVATOR PITCH
Jon Howard: WHERE IN THE WORLD? INTERCONTINENTAL BALLISTIC FLASH
Joa Ebert: 1 1 7 11 21
Seb Lee-Delisle: WHAT THE FLUX!?
Veronique Brossier: ADOBE AIR FOR MOBILE DEVELOPMENT
Nando Costa: THE OTHER SIDE
Brendan Dawes: MAKERS OF THINGS

Wednesday:
6 OF THE BEST – 10 MINS EACH
Iain Lobb: ZERO TO GAME DESIGNER IN 60 MINUTES
Ralph Hauwert: UNITZEROONE :: THE DISCONTINUITY
Frank Reitberger: TRIANGLE AFFAIRS
Peter Elst: BIG BOYS AND THEIR LITL TOYS
Jared Tarbell: THE COMPUTATIONAL ARTIFACT

02
Mar
10

AS3 Magnifying Glass Class :: Pixelbender Lense Refraction

The AS3 Magnifying Glass is a lense refraction class employing PixelBender. The class is an encapsulated method that takes a source image, a position and radius and returns a refracted result in sprite form.

I needed to represent a spy glass in my current project, and was looking for a very efficient method to achieve this. PixelBender seemed the obvious route and I’m pretty impressed by the speeds I am getting. I have max-ed out the frame rate and am still getting full (120) fps.

The MagnifyingGlass effect is the resultant class. The class embeds a pixelbender filter that spherizes it’s input and returns this as a sprite.

When using the class, the source image should be sent to the MagnifyingGlass full size, and be displayed to the user at a reduced size. This helps to preserve the integrity of the refracted image.

Usage:


//refraction: 0=Lots, 1 =None
//radius: The radius of the magnifying glass
//position_point: The position of the magnifying glass on the source image
//source_pic: BitmapData of the source picture
magnifying_glass = new MagnifyingGlass(refraction,radius, posn_point, source_pic)

magnifying_glass.magnifyingGlassPosition=posn_point
magnifying_glass.update()

AS3 Magnifying Glass Class

The AS3 MagnifyingGlass Class

I have set up a quick demo that shows the class at work on 3 different images. Press any key to change the image.

Image#1: Have a look around a bit of England & Wales. Enjoy.
Image#2: Hundreds of cartoon characters. See if you can find Quagmire! – Gigity.
Image#3: There is a sheep in there somewhere.

NOTE: The PixelBender filter used here is based on Joa Ebert’s Spherize Filter originally built in Hydra – the forerunner of PixelBender.

NOTE: This requires Flash Player 10 and above.

Demo: Magnifying Glass Class Demo
Source: MagnifyingGlass.zip

25
Feb
10

AS3 Flamer Class :: Setting things on fire

The Flamer Class is a quick and easy method to set things on fire. Throw some fuel (any display object) at the class and make it burn.

While working on another project I needed to make some lightweight flames. I looked around, tried a bit of perlin noise, some convolution filters – then some PixelBender filtering – I wasn’t really happy with the results.

I found the excellent Saqoosha’s Fire on Wonderfl.
This demo had nearly the flicker and colour mapping that I was looking for. Rendering the perlin noise on each frame was causing a bit too much processor overhead for my purposes.
Instead of rendering two perlin octaves and moving the layers against each other, I took two separate single octave perlin noise bitmaps and rotated one against the other while blending.
This gives a nice effect and is very lightweight. With the Saqoosha method I was clocking at a steady 26fps, with my lightweight method I could get 90fps.

To get the flame hues I set up a gradient box, threw some colours at it, loaded those colours into an array which I then pushed to a palette map.

So how to use the Flamer class:


import swingpants.effect.Flamer

var flamer:Flamer=new Flamer(display_object)
addChild(flamer)

addEventListener(Event.ENTER_FRAME, enterFrameHandler)
function enterFrameHandler(event:Event):void
{
flamer.update()
}

Your object will now be on fire. Feel naughty?

You can set the render width and height and also set the direction of the flames by setting a point vector.


var flamer:Flamer=new Flamer(display_object,render_width, render_height, flame_direction_point)
addChild(flamer)

//The colour of the flames can be set with one of the presets (There are 4 at the moment – ORANGE_FLAME, BLUE_FLAME, YELLOW_FLAME, GREEN_FLAME – but I will be adding more)
flamer.setFlameColour(Flamer.BLUE_FLAME)

//Direction can be set on the fly:
flamer.setFlameDirection(direction_point)

Here is a demo of a pure code use of the Flamer: The Flaming Vortex. You can click on the flash to initiate an explosion, and pressing space will change the colour. Have a play:

Flaming Sun

Flamer Class. The flaming vortex demo

This next demo is an example of throwing a movieclip/sprite at the Flamer class. Don’t laugh, I quite literally spent 10 minutes putting the anims together then threw them at the Flamer. Click on Flash to change colour and object.

Flaming Car

Flamer Class Demo. Help, my car is on fire

Lots of fun can be had by throwing different animations at the Flamer. Control some with your mouse/keys. Become a twisted fire starter.

The Flamer class could do with a few more features, but is a pretty good start. The speed is pretty good, I’m happy to receive any improvement recommendations.

I have packed the Flamer class and demos up in a zip if you want to have a play:
DOWNLOAD: Flamer Class and Demos

DEMO #1: Flaming Vortex
DEMO #2: Burning Movieclips




Categories

Reasons to be Creative 2012

FITC Amsterdam 2012

Flash on the Beach 2011

Flash on the Beach 2010

Flash on the Beach 2009

Swingpants at FOTB2009

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