Tuesday, 27 September 2016

Sound and Motion

A couple of new experiments testing the Maximo system for use in Unity, and synchronising animation and sound together. I feel Unity is missing a sound bar in the animation timeline, which would enable more accurate synching, and be a big help with the animation.
The figure is again from my forthcoming AR book about the universe.

WebGL demo

Monday, 26 September 2016

We Are All Made of Stars...

I've been playing around with this fantastic dataset HYG. It contains 120,000 star positions and magnitudes. I've coupled it with the constellations from NASA and made a Sky map, that isn't a skymap. That is to say, it's made of particles rather than the traditional bitmap image.
Several advantages there. First I stripped down the data to the 10,000 stars visible to the naked eye.
The resulting dataset is about 450Kb, compared to several megs for a comparable image map.
Then I've changed the colour from pitch black to a inky blue, which is more the color you see most nights. Obviously that can be easily selected from the Camera background colour. The stars also shimmer ever so slightly. To add a bit of interest the constellations are interactive and display their name on mouse over.

This is part of a children's book I'm writing about the universe. More on that later...
Try it for yourself :) Mouse Wheel to zoom out and see the "star globe".

Monday, 12 September 2016

Fun with Particles

No matter what platform you use, sooner of later you're going to want to have a mess with particles.
The "fun" involved is trying to get them to do what you want. I've been playing with the Unity Particle system for a couple of days now. A lot can be achieved in the UI manually, but who wants to do things manually? So, getting to grips with the system via C# seemed (at first) the best way to go about it. The system has many ahem, idiosyncrasies that at times had me going mental, but in the end I managed to beat it into submission.

The result? I like to call it home. A little old place called the Milky Way...

The whole thing starts with a Big Bang (I am a stickler for details, so this does too).
Basically, you first have to generate all the necessary particles. It would be nice if you could set their size via script, but that would be too easy. Not all the properties you have at your disposal in the UI are available through the API, though there are workarounds for a few of them. I found I had to generate the particles first, then go back and scale them individually, not something you want in your Update function.

Issue 2. After piffling about drawing Force graphs to emit the particles in a nice spiral, I found it was WAY easier to rotate the emitter as it was generating the particles. This was great, only I had to do it in WORLD coordinates. No problem, except after generating them, you can't then rotate them, by rotating the parent object. So, after a few shandies I managed to figure out how to generate in world coordinates and then switch to LOCAL afterwards. All well and good, except for a strange anomaly.
When changing emitter to LOCAL (actually finished emitting at that point), the transformation the parent object already had somehow get's lost. So to summarize, first create your emitters, facing in the direction you want and spew your particles into world space. When finished change to LOCAL, and apply the transformation the parent object had before you switched. Simples!

I could write a short book about the ForceOverLifetime module, but I doubt it would be a best seller. If you ever mess with it, to attempt a circular motion, Good Luck! Just remember that if you apply a force in one direction you need to double the force to make it go in the other, so the usual SIN/COS technique for a circular path simply doesn't apply.

There's 40400 particles here, and I must admit I'm impressed with the performance, even on my 3 year old mobile.

It wasn't purely for fun, this is a to illustrate a page an AR book I'm writing for children to learn the wonders of the universe, from the Big Bang to the Special and General relativity. Hopefully that will be a best seller...

Sunday, 28 August 2016

Hello Unity, AIR I still love you.

It's been quite a slow summer workwise, so I've had plenty time on my hands.
I've been toying with an idea to create a "digital pop-up book", that is to say a book that comes complete with a google cardboard headset, and combines a story with Augmented and Virtual Reality.

I created the first version in AIR, and did manage to get everything working. However, performance was not great. I was using four Stage3D Proxies, which worked fine on my own phone, an Oppo 7 Find, but on smaller phones some levels would disappear for no apparent reason, though I suspect there wasn't enough VRAM available. The Oppo has a dedicated graphics chip, and can easily fool you into thinking everything's pukka.

So, time to look at alternatives. I've messed with Unity since the very early days, when I actually talked with David Helgason, one of the founders, and got a free license. The whole thing started in Denmark, and I was a member of the Web3D Consortium, still trying to make solutions with X3D. At this time Flash ruled supreme, so there was no point (for me) to learn Unity. I'd made a javascript bridge between Flux Player (a then open-source X3D engine) and Flash Player, and was having a whale of a time programming in ActionScript and seeing results in 3D. Made a few good solutions on that basis, before Flux player suddenly became a closed technology, and carried a very hefty license fee.

Just when I thought I would have to drop Flash, in order to carry on working with Web3D, Stage3D came along and I've rarely looked back since. But it's time to look forward.

Now, as then, when I open Unity I can't help feeling I've gone back to the Flash MX days.
Attaching scripts to actual graphical objects the way we used to, each MovieClip having an onClipEvent(load) and onClipEvent(enterFrame). I wonder if that was the inspiration for Unity's Start(), Update() template?
In Unity the MovieClip is loosely replaced by the GameObject. That's another thing that put me off Unity. It assumes you're making a game, which generally I'm not.

Unity allows you to program in JavaScript or C#. I was tempted to go with the JavaScript approach, but that seemed like a step backwards after all that AS3 OOP goodness, so I've learned to use C#.
The transition has been completely painless, for apart from slight differences in syntax, everything is quite familiar.

I'm used to sitting with pages of code in FlashDevelop, and only seeing my 3D creations after compiling. I actually wanted a similar workflow in Unity, though now I am getting used to the way Unity works, and the ability to create structure, without necessarily having a "Main" class.
(I found out how to do that too, but don't need my comfort blanket quite as much any more :)
In Unity you do set a lot of variable and properties through the User Interface, but the user interface is created from your own code, so basically if you work the way I do, you are building a custom user interface for Editing and tweeking your application as you go along. This is actually a very cool approach. I just never got that far in my previous brief attempts to master Unity.

Once you discover the power of a full blown 3D engine, it's easy to go mad.
As I work primarily on Mobile and tablet, I have had to tone it down a bit, but it's fantastic to be able to work in a WYSIWYG environment again, the way we used to in the early Flash years.

Visual Studio is a pleasure to code in. Once I got the intellisense working, I've been able to use it to discover all the properties and methods available on different types of objects and I'm now feeling just as at home as in FlashDevelop.

Unlike most Flashers, I'm not quitting AS3 to take up a new technology, just adding to my toolbox.
Now I'm feeling comfortable with C# a whole new world has opened up and I'm excited to see where it takes me.

My first experiments have been in "Mixed Reality", that is a combination of Virtual and Augmented reality using the Vuforia library. Sometimes it's so easy it feels like cheating. While ActionScript has always been a challenging platform to master (and therefore in itself very satisfying when getting something to work!!), the combination of Unity and C# provides a powerhouse of new possibilities, as all the simple stuff is taken care of. I'm not used to anything being "under the hood", and even libraries like Away3D, I've customised and modified for my own ends.

Though I've had to go from Flash Hero to Unity Zero, I'm quickly clawing my way up to where I can call myself a Unity Developer.