So yeah, lots going on.

In the next month or so I’ll be transitioning over to a new host as wordpress.com doesn’t meet my up-coming needs. Look for it soon!

The basic idea of the framework is to provide a platform for building web-based applications. That means it’s a library nothing like jQuery where you pick and choose what elements of jQuery you want, Cappuccinno is an all-or-nothing solution.

The thing I found most interesting was that the JavaScript you write is actually written in a language they call Objective-J. At its heart, it is Objective-C for JavaScript. This is pretty compelling as in theory you could more easily port an exisiting Cocoa application for the web. In practice, this is a long ways out as there is a lot of the underlying framework missing.

I did find writing the Objective-J code very familiar as I’ve used Objective-C in the past. Is this the new way to write web apps? I don’t know… definitely needs some work to before it truly becomes a v1 product, but it has potential.

Some might cringe that it abstracts the “HTML-ness” away from the web, but I don’t necessarily think that is a bad thing.

The most interesting thing about Cappuccinno, to me at least, is there Atlas project. It’s basically Interface Builder for JavaScript, which I find very interesting. They also have tools to convert your Nib files to Cib (basically a Cappuccino Nib file) files which allow you to load up UI that way.

It’s definitely a framework you should look into if you are developing a new web-app from scratch. It obviously doesn’t have the widespread use like jQuery does, but that’s not always a bad thing.

Canvas is currently so limited that you cannot even draw a simple dashed line! Straight lines, no problem.

This is clearly a problem that needs fixing and luckily enough, I have just a solution.

So, how might we go about adding this functionality. Quite simply! Thanks to the ability for JavaScript’s prototypical nature, and maybe more accurately, it’s dynamic nature, we can extend the functionality of the Canvas object so that we can make our new functionality look like it’s built-in.

Ok, so how do we get started? First we need to define our protype code. I’ve created a new JavaScript file called canvas.js to where we’ll put our code.

CanvasRenderingContext2D.prototype.dashedLineTo = function (from, to, pattern) {}

That adds the ‘dashedLineTo’ function to our canvas protype.

Next we need to actually implement the function. I’m not going to actually go through and explain it all, but the idea of the code is to use the pattern parameter to define the length of each dash and each space, in alternating order, for your dashed line.

CanvasRenderingContext2D.prototype.dashedLineTo = function (fromX, fromY, toX, toY, pattern) {
  // Our growth rate for our line can be one of the following:
  //   (+,+), (+,-), (-,+), (-,-)
  // Because of this, our algorithm needs to understand if the x-coord and
  // y-coord should be getting smaller or larger and properly cap the values
  // based on (x,y).
  var lt = function (a, b) { return a <= b; };
  var gt = function (a, b) { return a >= b; };
  var capmin = function (a, b) { return Math.min(a, b); };
  var capmax = function (a, b) { return Math.max(a, b); };

  var checkX = { thereYet: gt, cap: capmin };
  var checkY = { thereYet: gt, cap: capmin };

  if (fromY - toY > 0) {
    checkY.thereYet = lt;
    checkY.cap = capmax;
  }
  if (fromX - toX > 0) {
    checkX.thereYet = lt;
    checkX.cap = capmax;
  }

  this.moveTo(fromX, fromY);
  var offsetX = fromX;
  var offsetY = fromY;
  var idx = 0, dash = true;
  while (!(checkX.thereYet(offsetX, toX) && checkY.thereYet(offsetY, toY))) {
    var ang = Math.atan2(toY - fromY, toX - fromX);
    var len = pattern[idx];

    offsetX = checkX.cap(toX, offsetX + (Math.cos(ang) * len));
    offsetY = checkY.cap(toY, offsetY + (Math.sin(ang) * len));

    if (dash) this.lineTo(offsetX, offsetY);
    else this.moveTo(offsetX, offsetY);

    idx = (idx + 1) % pattern.length;
    dash = !dash;
  }
};

To use this code, just include your new canvas.js script file in your .html file in a script tag, and voila!

  <script type="text/javascript" src="canvas.js"><script>

If you know of a better way to do this, be sure to let me know!

Update: So, maybe I should have tested that version. Updated the code to actually work and not rely on some other pieces of a library I’m working on.

Well… I’d like that to change. I’ve got a lot of cruft up in this old brain of mine and it’s time to post some of that in hopes that others may find it useful, or maybe just amusing at the very least.

I’ve got a new job, still at the same company, just with a different group. So far it’s been great, APP BUILDING APP BUILDING APP BUILDING! Of course, the fun will end shortly as we get back to some serious work. One of the best things about this job is that I’ve gotten back into, or shall I say more accurately, actually getting into JavaScript.

I’ve forgotten how fun dynamic languages are. Having spent most of my time in C# or C++ in the past few years, it’s freeing to be able to spend a significant amount of time in a language where I don’t have to come up with a class, where if I need a function to do something I can just create it inline and pass it around like a normal variable, or where parsing a string doesn’t take 10 lines of code… yeah, I’m looking at C++!

Anyway, the point is that I’ll be blocking off some time every week to two to write up a blog about something helpful that I learned, most likely pertaining to some problem I’ve faced, in hopes that some other poor sap won’t have to go through the same ordeal I have but can use my solution and move on to solving his/her real problem at hand.

See you soon!

It turns out there is a fairly ridiculous bug in the .NET Framework 4 Beta 2 setup. The basics is that it tries to find a drive to extract out the setup file (why the current drive isn’t good enough is beyond me) and extract out the files there… well, on my setup with Bootcamp that gives me a 160GB partition with OS X and an 80GB partition for Windows. Well, the setup finds the E drive (I have Snow Leopard so I can read HFS drives in Windows) which is my OS X drive and the drive with the most free disk space. Next it tries to extract itself out to it but fails as the HFS partition is read-only.

The workaround is fairly easy to do and the bug should be fixed by the time RTM comes. To fix it, simply remove the drive letter mapping from your OS X drive in Windows, install the .NET Framework 4 Beta 2, and then add the drive letter back to your OS X partition.

After that, all should be happy.

So there we have it… we’ll see how long it lasts.

Anyhoo, check it out, it’s a fun little game. Though don’t go expecting a conversion of your typical PnP experience.

Build and Analyze… waiting, 17 issues!!! Oops!

Here’s a quick shot of one of the issues that it found:

So I’m sure all of you seasoned Objective-C programmers are laughing out there at me right now, but what can I say, I’m still learning this whole retain-count memory management.

Needless to say, I was astounded that the compiler was able to figure this out for me. This will obviously be extremely handy for all of those new Objective-C programmers (and even veteran) that forget to release that memory when you’re done with it.

Clang is able to find other types of issues as well, like coding standards violations. For instance, I had a message named withName:(NSString*) and Clang realized that I was returning an instance and control of the memory and that my message name didn’t start with ‘copy’, ‘new’ or ‘alloc’.

Overall, I was actually quite impressed at what Clang was able to do. So yeah, if you have Snow Leopard and you’re a developer, you should definitely switch your projects to use the Clang compiler (unless your projects are C++, Clang doesn’t currently support that language).

For more Clang information, check it out here: http://clang.llvm.org/.

I was being plagued by feature creep so I decided to tone back a little and get it out the door. I would have released it last week, but I was out of town for a majority of it and it didn’t feel right to release something and then be on hiatus.

If you find any bugs, log them here: http://bitbucket.org/owensd/plexer/issues/.

Enjoy!