Tutorials/Minecraft demo on OSX

I have an iMac running 10.8.3 and when my son tried to run the demo version it failed with the "white screen of death" commonly reported. Well, being a long-in-the-tooth developer that wasn't going to do!

I first followed the instructions on this page: LWJGL which actually did remove the original problem, not being able to create the LAWT surface or whatever it was but it did result in some more problems with other permissions, one of which was not being able to read the LWJGL "debug"property.

This called for me to dust of some rusty Java knowledge about setting up a property file containing permissions.

I will spare you the details but here is how to get Minecraft (the demo version) running on Firefox on an iMac, of course YMMV depending upon what versions of software OSX you have. For the record, here are my system details:

*Firefox 20.0 *Software OS X 10.8.3 *Memory 4 GB 800 MHz DDR2 SDRAM *Processor 2.66 GHz Intel Core 2 Duo *Graphics ATI Radeon HD 2600 Pro 256 MB

So here's the process...


 * 1) Follow the instructions on the page to the letter, they really do have a positive result towards getting it to run in the browser.
 * 2) Create a file called '.java.policy' in your home folder. For example, if you login name is "eric" then the file you want to create will be called /Users/eric/.java.policy
 * 3) Edit this file and then cut-and-paste the following into it exactly. Here is the content you will need:

grant { permission java.security.AllPermission "/Users/eric/-", "read"; };

Once you have saved the file, quite Firefox and then return to the site, log-in and start the demo... it should now run. If it doesn't, sorry but you must have done something different or have some other problem.

What we have done is told the Java run-time that it's OK for everything in your account folder to be read by running applications. I will maybe experiment with this to restrict it to the net.minecraft.Launcherclass but I had already spent a lot of time getting it to run. Take note that this is potentially insecure in-so-much as you are now allowing any Java application to read from your folder.It should be a problem though.

Presumably the latter part of the cure, the property file, is only necessary for running the demo version in the browser.

If I can make a screen capture of the process from start to finish sometime soon then I will post it on YouTube and place a link here.