Chugging along on Magecrawl for SL...

Quick update:

I'm still chugging along on Magecrawl for Silverlight. I just finished ranged targetting with overlays, which makes melee/ranged attacks, inventory/spell use, and operate doors work.

I have a bunch of "easy" dialog work to do, a splash screen to make, animations for ranged attacks, etc. I also have the harder work of a skill tree, preferences, and such.

[Silverlight] ChildWindow focus bugs, oh my!

Another day of programming, another bug in silverlight to work around. When I'm not working around bugs, I'm crazy productive however.

The issue today is key focus, in particular with ChildWindow. This class allows you to place modal dialogs up with a minimal of fuss. The problem is that for some reason they weren't getting keyboard focus correctly. This is a big problem when you want your entire game to be able to be run from the keyboard alone.

Here is my solution (with help from a friend):

public ChildWindowNoFade ParentWindow;

        public ChildWindowNoFade()
        {
            this.DefaultStyleKey = typeof(ChildWindowNoFade);
            this.Loaded += new RoutedEventHandler(ChildWindowNoFade_Loaded);
            this.Closing += new EventHandler<System.ComponentModel.CancelEventArgs>(ChildWindowNoFade_Closing);
        }

        void ChildWindowNoFade_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            Dispatcher.BeginInvoke(() =>
            {
                if (ParentWindow != null)
                {
                    ParentWindow.Focus();
                    if (ParentWindow.InitialFocusItem != null)
                        ParentWindow.InitialFocusItem.Focus();
                }
            });
        }

        void ChildWindowNoFade_Loaded(object sender, RoutedEventArgs e)
        {
            Dispatcher.BeginInvoke(() => 
            {
                Focus();
                if (InitialFocusItem != null)
                    InitialFocusItem.Focus();
            });
        }

        protected abstract Control InitialFocusItem
        {
            get;
        }

Roughly, I'm creating a base class that hooks into loading and closing of windows. It fixes up the focus problems in cases of stacked modal dialog (where ParentWindow is non-null).

A few other notes:

• Some child windows act funny with keyboard focus if they don't have controls in them and/or they don't have IsTabStop="True" TabIndex="1" set on the window
• System.Windows.Browser.HtmlPage.Plugin.Focus();    If you call this guy on the creation of your root object will give your application focus.

[Silverlight] Binding to list box elements throwing MethodAccessException

I spent an hour or two figuring this out, so I figured I'd post about it. Hopefully, the next poor soul who runs into it will find it here:

I was running into a problem binding my list to a Silverlight list box. On listbox creation, the output window had lots of lines that looked like this:


System.Windows.Data Error: Cannot get 'DisplayName' value (type 'System.String') from 'Magecrawl.Items.Consumable' (type 'Magecrawl.Items.Consumable'). BindingExpression: Path='DisplayName' DataItem='Magecrawl.Items.Consumable' (HashCode=45492604); target element is 'System.Windows.Controls.TextBlock' (Name=''); target property is 'Text' (type 'System.String').. System.MethodAccessException: Attempt by method 'System.Windows.CLRPropertyListener.get_Value()' to access method 'Magecrawl.Items.Consumable.get_DisplayName()' failed.
   at System.RuntimeMethodHandle.PerformSecurityCheck(Object obj, RuntimeMethodHandleInternal method, RuntimeType parent, UInt32 invocationFlags)
   at System.RuntimeMethodHandle.PerformSecurityCheck(Object obj, IRuntimeMethodInfo method, RuntimeType parent, UInt32 invocationFlags)

The answer is that under Silverlight, you can not bind to non-public objects. The Consumable objects noted above was a internal object with a public interface. Once I made it public, the problem went away.

A side note, this apparently also occurs if you bind to an anonymous type as well.

Silverlight fun and arcane "batteries"

While the open beta of Final Fantasy 14 has taken more programming time away that I'd like to admit, I haven't dropped off the face of the planet yet. I've made good progress so far on the new "tiles" GUI, using silverlight. See this video for a quick video of gameplay. There is a huge number of things needed to make it fully functional, ranging from picking up items to the skill tree.

Assuming I was able to make the tiles interface work on Windows/Mac/Linux, both in the web browser and in a stand alone application, I've been toying around with the idea of ditching the ascii interface. I personally enjoy playing the tiles version of crawl more than the ascii version, and I feel I could make either two decent front ends or one awesome one. There is a lot of "if"s still in the air, but would doing that enrage anybody out there? While in the end I'm programming this game for personal pleasure, I do care about the opinions of the players of my game.

Another idea floating around my head is redesigning the magic system in Magecrawl. Right now, it is a fantasy standard MP system, with the MP being generally recharged after every fight. This makes fights "front heavy" with the characters dumping most of their MP early on, and resorting to melee afterwards. Also, it generally devolves into spamming the most powerful attack spell over and over. When I think about arcane duels, this isn't how I imagine things. I imagine almost every round until exhaustion some spell being cast, whether it is a earth-shaking powerful effect or a simple cantrip.

It is hard to make such a wide spread of spell types and tempos effective in the current system. My idea is a take on recharge magic, with a twist. Each spell has a total amount of "energy" that is needed to cast it. The player has a "battery" of mana, which at the end of each turn (that isn't spent moving?) some is syphoned off to fill each skill not ready to cast.

With a property selection of spells, one could alternate between two relatively fast recharging spells, or cast a range of spells (damage, push back, damage, blink away). Long term effects could reduce either the total "battery" before spells start running dry or the rate that spells recharge. Playing arcane characters should be about casting spells and making things blow up :)

I can has magecrawl on the internets?

So it might not look like much, but that's magecrawl running in a web browser! Levels generated, items created, monsters waiting for time to start ticking. The only thing missing is drawing and control.

My good friend Ben inspired the idea and helped implement some the magic.

Roughly the magic entails removing all references to libtcod from the game engine. That way, we can load all that code inside a web browser via silverlight, (which can't load native code). I "ported" this code from libtcod:

• Shadowcasting Line of Sight
• A* Pathfinding
• Bresenham Line Generation

"Porting" could be described as the twisted application of force needed to move C code to compile and run in C#. Since none of them used pointer math too heavily, it was reasonable to attempt. The code looks ugly for C# code, but it works.

In theory, it should even save and load! I can use my same serialization code, just point it to "isolated storage" and away we go.

Obviously, a lot of work is needed to make it a real game frontend. But the fact that I could even get this far (and not have to rewrite everything in flash) is pretty awesome.