BENNY BOTTEMA

Here’s a list implementation I came up with to enable true paged data fetching completely transparent to any List user. It works independent of persistence layers, such as JPA implementations etc and it can be used by anything that only needs a List, such as a < rich:dataTable >.

• PagedList source files on GitHub

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Here’s a tutorial about a possible way to create planets and indeed Earth. I’ll briefly explain the main textures used and from then on go through the code step-by-step to explain what I did and why.

I had to tone down the size and fps, and leave out the bumpmap for this demo because my Opera browser was halting when I added the other images and clouds swf demo 😛

• Download Clouded planet Earth source

On my core 2 duo laptop I get about 20-25 fps whith a slightly larger stage size and the movie set to 30 fps. Although the planet looks very nice to me, I also realize it isn’t very practical for games or other realtime simulations. To get better fps, you can remove the bumpmap texture, replace the realtime clouds with a fixed texture, user fewer segments in the spheres, zoom out more, or use lower resolution textures for land- and cloud materials. A combination of two or more of these suggestions should easily get you above 35 fps.

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Here’s a small class I made for adding realtime updates to DisplayObject3D objects. This class allows for easy time-based updates instead of the traditional frame-based updates.

• RealtimeDisplayObject3D.as

I use the convention of adding update methods to all (my own) DisplayObject3D objects, which then update themselves according to preconfigured settings (eg. passed in the constructor). I pass in a Camera3D and that’s it, let the objects do their own thing. I’m making use of this convention by extracting this update method to a baseclass which then can do time-based updates instead.

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Many space shooters use this concept where you are the pilot that looks out from the front window, lasering down enemies for bounty, right. Ever noticed spacedust? It’s very subtle when it is used, but it adds to the realism of outer space, making the space feel less empty, less static.

Here’s how you can do that in Papervision3D, using ParticleFields. I’ve used the trunk of the papervision code repository, revision 851, but it should work with the last release without to much hassle. Note that I’m no PV3D guru; I just started to learn this stuff and I’m just sharing what I’ve learned so far.

Here’s how it works:
• divide space into a 3d grid and parts of the spacedust cloud on 8 gridpoints directly around the camera (the ship), we’ll call these dustpockets
• when the camera moves, dustpockets are removed and created to keep only the 8 gridpoints around the ship occupied

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JSF is hard to learn yes, but in my opinion it doesn’t suck as bad as Wille says. All the points Wille mentions can be solved by certain libraries or write-once reusable solutions (I’ve included my ‘magical’ combination of frameworks on the bottom). JSF is a diamond in the rough, you just need to make it shine.

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Here’s the story about why I wrote a mail API wrapper in Java and made it Open Source. It is called Vesijama, Very Simple Java Mail.

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Vesijama has been renamed and moved to Simple Java Mail!

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Yes, it is possible. Yes, it requires hacking JSF with filters and/or phaselisteners and/or custom servlets for encoding/decoding serializing/deserializing GET parameters and force redirects upon JSF view resolvers. The good news however: it’s all been done before and you can just hang back and use a small framework that does all this stuff for you. Enter PrettyFaces.

But before we come to that, I would like to show you how PrettyFaces sums up what you need. This involves solving two problems: The JSF POST compulsion and the JSF Redirect problem. You can in fact solve all of these problems separately, but PrettyFaces just encapsulates all these annoying things for you in a convenient little jar.

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If you’re trying to deploy a war under Tomcat and it isn’t going like it should be, the first thing you do is look in the console if you ran it from a console, or the log files in Tomcat’s homefolder otherwise. Now this provides you with some details as to why something went wrong, but there is the chance that de application itself is throwing exceptions unlogged which are caught by Tomcat. Those are not logged by default by Tomcat! To log these as well, you’ll need to utilize log4j.

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You’d be surprised how hard it is to find good information about how you’re supposed to setup validators that you can parameterize with attributes in your tags; most about validators is very basic and very JSF-only. Or you won’t be surprised at all, because you searched until loss of sanity like me and found this blog. Whatever, here you can read what I found out.

So at first I made the error in not realizing validators under Facelets should be defined in their own facelets tag library. I hadn’t really worked myself into the the theory behind Facelets; I just picked it up as I went… as I do with most things, but there you have it. Turns out Facelets actually makes things very easy concerning validators, were it not for one sneaky little detail:

“parameterizable validators are stateful validators“

We’ll come back to it, but validators generally lose state after the page has been built by Facelets and you have to manually restore that state (including the previously set parameters), by implementing the StateHolder interface.

Oracle has a good article on StateHolder Validators, though I only found it after I learned what to look for.

I resorted to a rather crude catch’em all solution, that tucks away the boilerplate code involved.

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