Post Archive - January 0001 wharbargle

Posts tagged code

code HenchLua Lua

This is the first of a series of posts on the subject of HenchLua. HenchLua is an implementation of the Lua VM in C#. It's targeted at projects running in otherwise limited .NET contexts, such as web-based Unity games (the Unity plugin, I believe, requires pure verifiable CIL), mobile apps (which are memory-limited and must meet the limitations of Mono's full AOT compiler, or apps that run on the .NET Compact Framework (whose garbage collector has some serious performance issues, as anyone who's written an XNA game targeted at the Xbox can attest). ... Read more

code Windows WPF

WPF makes it easy to animate numbers, colors, sizes, and a host of other properties. Unfortunately, it isn't easy to animate an ImageSource property, which is what we're usually looking for when implementing a flip book animation. The closest we get out of the box is ObjectAnimationUsingKeyFrames, which works, but it's very tedious to set up all of the individual key frame times. ... Read more

code Windows WPF

Using custom icons can be a little tricky in WPF. It's simple enough if you want to use your application's main icon or an icon file that you can refer to using a pack URI - so long as you do that, everything just works. ... Read more

code Windows

There are times when you need an icon file, but all you have is an icon resource embedded in a PE (executable) file. Getting at these is a little tricky, since icon files aren't stored as a simple blob in the PE file. In fact, they're split up into a number of different entries. Fortunately, it isn't very hard to combine these entries into an ICO-format data blob which you can then save to file or pass to an API that expects it. ... Read more

code Windows

Most native applications make extensive use of Win32 resources. While the .NET Framework provides a far more useful resource API, it's sometimes necessary to access the old style Win32 resources. Fortunately, this isn't very difficult. ... Read more

code graphics Windows

Windowed (fake) fullscreen is probably my favorite graphics option ever when it comes to PC games. It lets me have my nice fullscreen game, but doesn't lock me out of using my other monitor, and any programs running behind the game are an instant ALT+TAB away. Games that can go from fully windowed to fake-fullscreened in an instant are also super cool, and not all that difficult to write. So how does one implement such a thing? ... Read more


One of the common requirements in game development is that we need to load large blocks of (usually) compressed data in as little time as possible. This, however, is somewhat easier said than done. Ideally, what we're looking for is a simple asynchronous I/O API. ... Read more

code security

One of the things that comes up when sending data over the internet is verifying that it hasn't been corrupted. This is generally a simple thing to resolve: send the data and a good hash (MD5 or SHA-1) of the data together. Recompute the hash on the client side and compare it to the hash you sent. If any bits have changed, the two won't match, and you know you need to redownload the file. I suppose it's possible both the data and hash could be corrupted in such a way that they match, but if your hash function is any good then the likelihood of this happening by chance is so astonishingly low that it doesn't bear consideration. ... Read more


Recently wrote some asynchronous I/O code for a fast data loader. The data file was logically a stream of separate objects, so it made sense to parse it a chunk at a time. That's a situation which practically screams for asynchronous I/O. Unfortunately, it's rather hard to find a useful example on how to use the relevant APIs... ... Read more

build iOS

This is a bug that's bit me a few times already. Basically, the iOS compiler fails to generate some function somewhere in the code file causing it to bail with the error "invalid offset, value too big". Problem is, it doesn't tell you which function it failed on (the numbers surrounding the error seem largely meaningless). ... Read more

code WPF

Got a crash in, of all things, System.Windows.Controls.Primitives.Popup.OnWindowResize(Object sender, AutoResizedEventArgs e). A NullReferenceException, to be precise. Ages later, it turns out that this error was actually caused by a binding operation on one of the controls in the popup failing because it was trying to instantiate itself as TwoWay with a read-only source property. Somehow, the binding error managed to turn into the NullReferenceException in the layout pass... ... Read more

code shaders

Hooking up a large number of shared effect parameters to a single head parameter via cgConnectParameter is, apparently, not the intended use case. Doing so causes any cgSetParameter call on the head parameter to become orders of magnitude slower (though the amount is proportional to the number of connected effect parameters). This is also the case when deferred parameter setting is used, which is a fairly surprising result, given that it should mean that parameter values don't force any sort of evaluation until something actually goes to read from them. ... Read more