Installing Parallels Tools on Debian 7

This entry is about remembering how I solved this issue (as well as boost some traffix for the blogger that solved it)

Parallels Tools is a package designed to make various host/guest tools work: Clipboard, shared folders etc.

For some reason though, the Parallels' way of installing it fails. And it turns out to be a mount + security problem.

First off, the iso wouldn't mount when choosing the "Virtual Machine -> Install Parallels Tools". So I had to manually find it using the "Devices -> Cd/Dvd -> Connect Image..." and browsing to "/Applications/Parallels\ Desktop.app/Contents/Resources/Tools/prl-tools-lin.iso"

But, it still wouldn't work. So, after some googling I followed this guide: Install Parallels Tools on a Debian Virtual Machine

In short these commands (on the guest) solved the issue once I got the iso mounted:

Eclipse + SSH

I work a lot across multiple systems of various OS'es and configurations, and usually I do it via ssh. However, almost everytime, the tasks get much slower than they ought to be, due to the fact that the remote system doesn't have your local tools and configs.

Since I mostly use Eclipse on my local system, and since it's plugin based, I thought of searching for such plugins, and imagine my surprise that it actually exists!

It's built in, and it's called Remote System Explorer.

C++ / Python / C# speed

The beginning

Even though there are many language tests out there on the internet, I wanted to have a go at it myself, to find out the cases I wanted to know about and to have control over the test. Also, I wanted to do it because I thought it might be fun to write a little testing framework and reporting tools! (And it would make some nice weekend programming)

But even though this might be a bit whimsical, one real question I've had for some time is "how fast/slow is Python compared to C#" (Or C++ even) ? So I went ahead and tested the languages I come across most often: C++, Python & C#.

If you want to skip to the results, here they are:

http://jcash.github.io/languagetests/

And here is the code:

https://github.com/JCash/languagetests

Compacting Virtual Box Drives

Too many times I've forgotten the exact commands on how to compact the virtual drives. Especially for windows, where the tool used, used to have a different name of the argument passed to it. Compacting the drive can save you lots of disc space (last time my drive went from 12GB to 5GB), and for a smaller lap top drive, that makes a big difference.

Windows Guest:
Download SDelete from SysInternals and then run

Linux Guest:
Here, we create a file that fills the entire empty space, and then deleting it:
Host:
Finally, you let VirtualBox compact the drive

That's it really! I hope I'll remember it a little better this time.

Further info:
Use “sdelete -z” when Shrinking a Windows Guest’s Virtual Hard Drive
How to Compact a VirtualBox Ubuntu Guest’s VDI file

Qt Plugin Cache

When upgrading an application to use a newer Qt version (4.8), I stumbled across a weird issue with the sql plugin not loading correctly. Even though I triple checked the paths, it didn't work.

This was surprising since if I used the previous Qt version (4.7), my app worked fine!

After much trouble shooting and testing and googling, it turns out that there is a thing called the "Qt Plugin Cache"!

git (msys) + merge + araxis

I struggled with setting up the git environment for my windows environment.
And since it's easy to forget these things, I'll just add the command lines for it here:

binpacking + fonts

Skyline-BL (Bottom Left) with
rects sorted on height. Rotation of
the rects were not enabled.

During the holidays, I've been working with my hobbyist project of generating bitmap fonts. One of the issues I hadn't looked into yet was the problem of wasted space between the glyphs and rows. And while I still wasn't actively looking to solve that problem just yet, I stumbled upon a good read by Jukka Jylänki - "A thousand ways to pack the bin - A practical approach to two-dimensional rectangle bin packing" from 2010.

It was a nice explanation of the most common bin packing algorithms and it also came with public domain source code (Thanks Jukka!)