Experiment at the GGJ17

My biggest takeaway in my GGJ17 experience was implementing a ‘sprite sheet animation‘-selector based on a given angle. This is only applicable to 2D games with more than 2 views per animation. If you haven’t read about our game from my last post, you can get more info here.

Here are the requirements:

  • Surfers could go be going to the right, down right, down, down left, or left
  • Dolphins could go left, up left, up, up right, right
  • Tiki could point left, up left, up, up right, and right

Each of these directions is a sprite sheet/sequence animation. The solution:

  • Each direction is a game object that animates through the sprite sheet/sequence
  • These direction game objects are children of a selector game object
  • The criteria of the selector is based on an absolute direction (to a target object, mouse, etc)
  • The selector activates the direction closest to the criteria and deactivates all others

If the directions weren’t animations (like the Tiki pointing), then a simple sprite selector based on angle would be enough.

A public repo of the project can also be found here. Here’s a UnityPackage of the demo:

AnimationAngleSelector » Post
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Recommended Facebook Privacy Settings

This post is not related to Game Development or Programming but I find it relevant to spread this. Nonetheless, I hope you find this useful for your online reputation.

Have you ever had a stranger like a picture on your Facebook? Or someone you don’t know suddenly commenting on your status? Or did you know that whenever you get tagged, it shows up on your wall without your permission? But most importantly, do you want to have more control over the privacy of your Facebook profile? Continue reading


C Operator Precedence

Given the statement below, what is pf?

  1. a pointer to an array of 10 arrays of 5 pointers to functions, with float and double parameters, that return an int
  2. an array of 10 arrays of 5 pointers to pointers to functions, with float and double parameters, that return an int
  3. a pointer to a pointer to an array of 10 arrays of 5 functions, with float and double parameters, that return an int
  4. an array of 10 arrays of pointers to an array of 5 pointers to functions, with float and double parameters, that return an int

Continue reading


Touch Events in Unity3D

I’ve been working on Crazy Bugz for the past few days to take advantage of the 2D physics and sprites brought in by the latest version of Unity3D. Many things have been updated which reserves a post all by itself. For now, I want to discuss a discovery I made regarding the touch events. I’m not sure if this is iOS or Unity3D specific but I’ve built a work around that seems to be working for now 😀

For a demonstration, here’s a Unity3D package (requires 4.3). Build and test it on touch devices. I’ve only tested it for iOS devices. You can test it with Unity Remote but it has limitations like touch responsiveness which is critical for this demonstration.

14.3 KiB

First and foremost, I made a generic event handler for the different touch phases in TouchMonoBehavior.cs

The OnTouch* event handlers are all declared public virtual void and passes the Touch parameter. Meaning, each event handler could be called multiple times per Update() depending on how many touches there are (Input.touchCount). We can treat each touch separately by taking note of the finger id that comes with the touch.

All the while, I thought the touch phases have the following state diagram

Touch Phases State Diagram

Unfortunately, upon testing over and over again, it is POSSIBLE to start with Moved or Ended! I haven’t noticed if it could start with Stationary since I don’t use it for my projects at the moment. But my point here is that the Began phase CAN BE SKIPPED! I’m not sure if this is intentional but it’s happening and it got me pulling my hair for the past couple of days.

I’m using an object pool in my project where the objects react to touch. When the user touches, an object is created, let’s call that Object 0. When the user touches again, another object is created called Object 1. If Object 0 gets disabled (as part of the game mechanic) and the user touches again, Object 0 will be re-intialized and treated as something new. Objects don’t get destroyed, rather, they become disabled. This is basically how object pooling works.

Theoretically, every time a Began phase is encountered, a mirror is re-initialized in Crazy Bugz. The user can rotate or stretch this mirror by moving their finger which corresponds to the Moved phase. When the user releases their finger, an Ended phase is encountered and that mirror remains enabled until it gets disabled (shattered) by the laser. However, there are certain occasions where I touch and get a NullExceptionError. It turns out, my game is trying to look for a mirror with a specified finger id that was not created. This means, the Began phase was skipped!

As a work around, if in case the Began phase has been skipped and goes directly to Moved phase, I would treat that as a Began phase. In the case the Began phase has been skipped and goes directly to Ended, I would simply ignore it.

Not exactly the best solution but this will have to do.

The ideal case? Well, Began phase shouldn’t be skipped… ever 🙂