Silverlight Viewports
Posted by Dan Dobbs – November 14, 2007One thing you usually recognize about web-based games is that they generally have a fixed view. With a fixed view, your game world matches the web control 1:1. What if you want the game to take place in a larger space, like an entire world, or a galaxy. In the game world, you’d create a viewport or a camera that only displays a portion of the world. Unfortunately, Silverlight doesn’t have native support for viewports into a larger space. We decided to make it.
Source: CanvasViewport C# class
The CanvasViewport is a simple plugin class that can be used to create a viewport on any Canvas (it doesn’t have to be the main page). It works by manipulating the Canvas’ RenderTransform in response to programmed parameters.
Usage:
// Create a viewport on this canvas.
CanvasViewport _Viewport = new CanvasViewport(this);
// Create a viewport that is 320x240 in logical (original canvas) units
_Viewport.Size = new Size(320, 240);
// Set the center of this viewport to 500, 800 on the canvas
_Viewport.Center = new Point(500, 800);
// In a game, you can have the viewport track a player like this:
void Update()
{
_Player.Update();
_Viewport.Center = _Player.Position;
}
An added advantage to using viewports in XAML is that since XAML graphics are all vector based, zooming in and out dosen’t have all of the pixelation problems that working with raster graphics has. Here’s the orignal game without the viewport.
Here’s the game with a smaller viewport into the original world. (Notice that the UI and the Reticle doesn’t change size).
Have fun with your viewports.
Combo Box Component
Posted by Dan Dobbs – October 19, 2007
Here is a basic Combo Box component that is easy to implement and customize. It supports automatic scrolling when the number of items exceed the specified height and is fed by an array.
Silverlight scrollbar component: Updated for easy implementation
Posted by Dan Dobbs – October 2, 2007
Another update to the scrollbar component. Just made some tweaks to make it easier to implement/instantiate. It’s getting closer to more of an OOP style but it’s not all the way there yet. Now all you have to do is call/instantiate the scroller like this:
myScrollPanel=new createScrollablePanel(“sp1″, 10, 10, 100, 160, “V”, the_text, “#FFF”, 9, null, “#0000FF”)
with the following parameters…
unique name, xpos, ypos, width, height, direction, text, [text_color, text_size, text_font, bg_color]
bracketed items are optional, I haven’t converted the horizontal portion yet so only “V” (vertical) is available 
This makes it way easier when you have multiple scrollers on the page. The mouse wheel support also got carried over and works when the mouse is over the particular textfield you want to wheel thru. There are now properties in the constructor to control other options like color, spacing, etc.
Silverlight scrollbar component: Updated with MouseWheel Support
Posted by Dan Dobbs – September 26, 2007
Here is an updated version of the scrollbar component I released earlier but this new version has Mouse Wheel Support:
Thanks to Adomas Paltanavičius for the Javascript that handles the Mouse Wheel events!