JSEDLAK » Coding

Archive for the ‘Coding’ Category

FGF 0.1.2.0 Released with Gesture Recognition

New to the input engine within the Focused Games Framework is the gesture recognition capabilities, housed in the GestureTracker class. The gesture recognition class currently supports a small subset of the gestures I plan on supporting, but all are useful none-the-less. The included gestures are press, two fingered press, swipe, two fingered swipe, zoom and pinch. To use the gesture recognition, instantiate a GestureTracker object, add it to the IGame.Modules list and then listen to its GestureTracked even. You will also need an instance of the InputManager class added to the list of modules.

The following is a small sample taken from one of my games that handles some simple menu swiping (a full sample is on the way).

If you do happen to use FGF, I would love to hear what you think! Drop me a line via the Contact form or leave a comment here.

?View Code CSHARP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
private void OnGestureTracked(object sender, GestureArgs args)
{
    // If it wasn't a swipe, we don't care!
    if (args.Gesture != Gesture.Swipe) return;
 
    // Get the direction of the swipe to determine what way
    // the menus should move
    if (args.Direction.X < 0)
    {
        // If we are capped at the right side of the menus, return
        if (current == menus.Length - 1) return;
 
        // Transition the menus
        menus[current].Transition(Menu.MoveDir.OffToLeft);
 
        current++;
 
        menus[current].Transition(Menu.MoveDir.OnFromRight);
    }
    else
    {
        if (current == 0) return;
 
        menus[current].Transition(Menu.MoveDir.OffToRight);
 
        current--;
 
        menus[current].Transition(Menu.MoveDir.OnFromLeft);
    }
}

 Download FGF 0.1.2.0 Bin

Read the rest of this entry »

What is DMS?

During the last semester I was taking a class on ASP.NET where we formed teams to write a website from scratch. The website was a “project manager” that would help users maintain projects, employees and customers. Given my experience with ASP.NET prior to the class, my team hit the ground in a full on sprint. We hit a wall when it came time to bind the site’s controls to the data behind it, in this case a Microsoft SQL database. The problems weren’t associated with a lack of knowledge but rather the gross disconnect between interfaces and the data with which they associate. It is easy to think that a textbox on a page can represent a name, but how that name is actually filled in can be the most complicated process.

This is just one instance of running into issues with data. How many times have you used a converter of some sort to scrub data or used a validator to make sure it can be stored? How many times have you written the same try-catch block for the SqlConnection class? How many times have you written a statement with “XmlDocument” or an instance somewhere in the middle? I have come to realize that there within the .NET Framework, there are many classes to get all the work done, but they aren’t really put together in a unified way. When you look at all the data-oriented classes (e.g. System.Xml.*, System.Data.*) you will find that there is no grand picture. For some reason the framework architects didn’t take a step back and see a possibility to unify the approach to reaching, converting, validating and consuming data.

So what is DMS? In short, the Data Management System prototype is a look into how possible it is to unify the approach to using data and whether or not it can make a developer’s life easier. The first step is to consider open architectures that are highly extensible and configurable. The current version of the DMS Prototype is focusing on just that by experimenting with converting runtime objects to and from XML. The important part isn’t the conversion; XML serialization has been done to death before. The important part to take away is that the serialization is being done in an abstracted manner. It is trying to gain as much information as possible from as little information as possible. The fewer attributes a developer has to use and the more generic they are, the easier life will be.

Read the rest of this entry »

FGF: Modules, Not Components

As you no doubt saw in the writing of the Application class, FGF implements its own version of the XNA Framework’s component classes. The first major reason for doing so is that the builtin component classes require you to pass in a (Framework) Game object through the constructor. While this dependency can be circumvented by implementing the interfaces directly and supplying a manual workaround, the attempt is exactly that: a workaround. The second major reason for my implementation is that by controlling the interfaces and base classes, I can easily support more advanced situations such as the separation between initialization and content loading/unloading. You will see more of this later on when I modify the classes to support asynchronous content loading.

For now, the focus is being put on building a robust base for developers to start working with my framework. Because the goal is to fix the XNA Framework’s implementation, we begin with a simplification of the IGameComponent, IUpdateable and IDrawable interfaces. We combine these three into a single, multi-purpose interface, IModule.

?View Code CSHARP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
public interface IModule
{
    event EventHandler DrawOrderChanged;
    event EventHandler UpdateOrderChanged;
 
    void Initialize(IGame game);
 
    void Draw(GameTime gameTime);
    void Update(GameTime gameTime);
 
    int DrawOrder { get; }
    int UpdateOrder { get; }
 
    bool IsVisible { get; set; }
    bool IsEnabled { get; set; }
    bool IsInitialized { get; set; }
 
    IModule Parent { get; set; }
    ModuleCollection Modules { get; }
}

Read the rest of this entry »

FGF: A Collection Class with Events

For most purposes, the builtin collection classes supplied by the .NET Framework are terrific. They are simple and straight forward implementations that do exactly as you expect. But for our purposes, a collection class that fires events when the collection is changed is simply better and in some cases, necessary. For this class, we make the jump over to the FocusedGames.Collections namespace, maintained in the FocusedGames library.

Before writing the collection class itself, we need a delegate that can define how our events will work. Enter the CollectionChangedHandler delegate.

?View Code CSHARP
1
public delegate void CollectionChangedHandler(object sender, CollectionChangedEventArgs args);

As you can see, we need to define the CollectionChangedEventArgs class itself. This is a simple class that has two properties. The two properties help listeners of the events to understand how the collection was changed.

?View Code CSHARP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
public class CollectionChangedEventArgs : EventArgs
{
    public CollectionChangedEventArgs()
    {
    }
 
    public CollectionChangedEventArgs(object item)
    {
        Item = item;
    }
 
    public CollectionChangedEventArgs(object item, int index)
        : this(item)
    {
        Index = index;
    }
 
    public object Item { get; set; }
    public int Index { get; set; }
}

Read the rest of this entry »

FGF: A Base Class For INotifyPropertyChanged

One piece of functionality I consistently find myself writing and rewriting is the implementation of the INotifyPropertyChanged interface. This class, located in the main FGF library, makes that rewriting unnecessary by implementing it in an open way.

?View Code CSHARP
1
2
3
4
5
public class NotifyPropertyChangedBase : INotifyPropertyChanged
{
    private bool isDirty = false;
 
    public event PropertyChangedEventHandler PropertyChanged;

Read the rest of this entry »

Linking To CSS Files In MasterPages

A common problem for beginning ASP.NET developers is relative linking to CSS files in a MasterPage file. As it turns out, this is incredibly easy as shown below. Even better is that it works in ASP.NET MVC!

1
<link rel="Stylesheet" href="<%= ResolveUrl("css/Master.css") %>" type="text/css" media="screen" />

FGF: Oriented Drawing

After you’ve read about the Display Orientation features of FGF, a natural question to ask is “How do I draw and take input with a rotated display?” Fortunately FGF has some methods to help in this department that sit alongside the rotation methods and properties in the Application class.

Application.OrientedDisplaySize

If you need to draw something relative to the size of the screen, use the OrientedDisplaySize property of the Application class. This property differs from DisplaySize, which is used to change the actual size of the display, in that OrientatedDisplaySize reacts to the selected rotation of the display, set with the DisplayOrientation property.

?View Code CSHARP
1
2
3
4
DisplaySize = new Vector2(272, 480);
DisplayOrientation = DisplayOrientation.Rotated;
 
Console.WriteLine(OrientedDisplaySize.ToString());

Because the display is set to be rotated (landscape on the Zune HD), the above code will actually print out a display size of (480, 272) rather than the standard (272, 480) size.

Read the rest of this entry »

FGF: Display Orientation on the Zune HD

New in the Focused Games Framework is the support for rotating and resizing the display on the fly. The main reason for this functionality is for mobile platforms like the Zune HD that support games in a landscape mode as well as a portrait mode. Supporting either in your game is made easy with FGF-you just need to know the right properties. In the standard display mode, the Zune HD has a display resolution of 272 pixels by 480 pixels. In landscape mode those two measurements are switched: 480 pixels by 272 pixels. While it is important to know the standard resolution, mucking about with a render target and backbuffer size is no longer necessary.

The one hitch? Your game class needs to inherit from FocusedGames.Xna.Application instead of Microsoft’s Game class. The following code block sets a Zune HD game up for landscape rendering.

?View Code CSHARP
1
2
3
4
5
6
7
8
9
10
11
public class Game1 : Application
{
    public Game1()
    {
        // Set the display size and the rotation
        DisplaySize = new Vector2(272, 480);
        DisplayOrientation = DisplayOrientation.Rotated;
    }
 
    // ...
}

Note that to keep the device in portrait mode, you don’t need to change the value of DisplayOrientation but setting the DisplaySize property to the standard value is a good idea. Happy landscaping!

Provider Model – Design Pattern

A design pattern made famous in the .NET community by Microsoft’s ASP.NET, the provider model explains is a pattern that supplies the end-developer with a plug-and-play architecture. The provider model is most often used when you have a consumer object that is dependent on specific functionality that can be supplied by one or more underlying systems. The major benefit of which is an increase in manageability and reusability.

Read the rest of this entry »

Re: Will Silverlight fix the web…?

It disgruntles me when poor arguments are put forth. For instance, Silverlight should be avoided is an argument that relies on a very biased opinion rather than fact. The problem, of course, isn’t that the argument is being made against Silverlight but rather that the argued points are unfounded and poorly written. Below is a point-by-point analysis and counter-point piece based on what I know of Silverlight as well as what Bing can tell me.

Hyperlinks

The author chooses, of course with no evidence, to make the point that Silverlight doesn’t support deep linking. I agree that providing a uri for each page, document, video, et cetera, is an important part of what makes the web accessible. Anyone who has visited an all Flash site from the late 90’s knows why: without a Uri, users cannot gain quick and consistent access to content. It is fortunate that Silverlight provides deep linking support, otherwise I would have to agree with the author. A quick Bing or Google search could have provided the author with this information, but then again what are facts to an argument?

Read the rest of this entry »