General news around the Internet

Silverlight vs. Flash

Tommy — Tue, 22 Jun 2010 10:26:58 +0000

A handy SDK for Facebook apps: www.microsoft.com/facebooksdk

In my Master’s thesis I used Adobe Flash (AS3) and creating games is quite easy in Flash. It’s an ECMA language as is Java, so it’s easy to work with. On the other hand the backend integration is quite tricky. Adobe Flash Media Server is not free, and the universities don’t have licenses for it either. That caused me a lot of problems which were learning experiences for me, but figuring out which open source projects would work was not related to the learning goals I had been trying to achieve with my interactive educational platform. It would be much easier to use .NET development through the entire project than try to provide Bridges between different programming languages through socket programming.

Since there is already guides about ASP.NET development and Facebook, in my opinion it will be easiest to integrate Silverlight with that. Microsoft provides a number of free downloads and free licenses for university students including Visual Studio, Windows Server 2008 R2, SQL Server 2008, etc. through the official Microsoft student website www.dreamspark.com, so it’s easy for student projects to get access to their products. Also, the really interesting thing about using Silverlight for your Facebook project would be that it would also work with the new Windows Phone 7 platform that will be released later in 2010.

Compiling OpenCV 2.0 with Visual Studio 2010

Tommy — Sat, 19 Jun 2010 10:24:31 +0000

I had a couple of troubles setting up OpenCV 2.0 in Microsoft Visual Studio 2010. I simply updated the working build from VS 2008. It had been working fine. So the first thing I found out that there was an error with “std::back_inserter”. The problem is that it was part of the standard package, but now it’s not. This trouble affects two files: “cvmodelest.ccp” and cvhog.cpp” so it’s easily cured by adding

#include

to cv.h. somewhere around line 60.

Another problem I encountered was a crash with videoInput.lib. It seems that it’s been compiled with VS2005 and it’s source code is not included. So with a bit of research I found that it’s not exactly a necessary thing to include anyway, so I followed the instructions:

http://www.opencv.org.cn/forum/viewtopic.php?f=1&t=9199

# On Windows: enabling the VideoInput library:

The libvideoInput.a library file provided by Willow Garage was built with the old SJLJ exception handling method. Therefore, you cannot link against it using compilers that use the new DWARF-2 exception handling method like MinGW 4.4.x, unless you rebuild the libvideoInput.a file using MinGW. The best bet for compilers using DWARF-2 is not to use VideoInput at all. This can be done by taking the following step:

1. Comment the line containing “#define HAVE_VIDEOINPUT 1″ (i.e. near line 101 or 105), in file src/highgui/_highgui.h.

In contrast, for old compilers using SJLJ like TDM, to have VideoInput included in OpenCV 2.0:

1. Edit file src/highgui/CMakeLists.txt
2. At line 199, insert ” ole32 oleaut32 uuid” at the end of the list of libraries to be linked against (i.e. after “videoInput strmiids”). The developers have forgotten to insert them.

Create new Froyo Virtual Device for Nexus One

Tommy — Sat, 29 May 2010 14:07:05 +0000

So it’s time to start developing Android apps, but you have a Nexus One running Froyo 2.2. What are you supposed to do at the stage “Create new Android Virtual Device (AVD)”? That’s exactly the question I was tackling today. In fact it’s not too important, since you would be developing for all types of Android phones, not just Nexus One, but in principle it seems right to set up the emulator exactly for the Nexus One.

So the first thing to do when creating a new virtual device is to give it a name. I was thinking about calling mine “NexusOne” but then I thought I should add a little more detail. However, there is a restriction in the naming policy: you are only allowed to include letters and numbers, no spaces or decimal points (but yes to underscores). This means the logical name “Nexus One Froyo 2.2″ is no good. Finally I settled on “Nexus_One_Froyo_2-2″. I selected Target: “Android 2.2 – API Level 8″. If you don’t have it as an option, you need to run the Android SDK updater.

Next select the size of the SD card. I put 2000 MiB.

And the skin of the Nexus One would correctly be WVGA800, which corresponds to 800 x 480 resolution. Technically it’s a slightly different since the particular screen used, but it’s effectively the WVGA800.

Next there’s a bunch of settings to add. I’ve seen some people suggest you need to add all the hardware components manually, but according to the following chart most of the stuff is there by default. (Chart is from http://www.51testing.com/?uid-49689-action-viewspace-itemid-212142)

Characteristic	Description	Property
Device ram size	The amount of physical RAM on the device, in megabytes. Default value is “96″.	hw.ramSize
Touch-screen support	Whether there is a touch screen or not on the device. Default value is “yes”.	hw.touchScreen
Trackball support	Whether there is a trackball on the device. Default value is “yes”.	hw.trackBall
Keyboard support	Whether the device has a QWERTY keyboard. Default value is “yes”.	hw.keyboard
DPad support	Whether the device has DPad keys. Default value is “yes”.	hw.dPad
GSM modem support	Whether there is a GSM modem in the device. Default value is “yes”.	hw.gsmModem
Camera support	Whether the device has a camera. Default value is “no”.	hw.camera
Maximum horizontal camera pixels	Default value is “640″.	hw.camera.maxHorizontalPixels
Maximum vertical camera pixels	Default value is “480″.	hw.camera.maxVerticalPixels
GPS support	Whether there is a GPS in the device. Default value is “yes”.	hw.gps
Battery support	Whether the device can run on a battery. Default value is “yes”.	hw.battery
Accelerometer	Whether there is an accelerometer in the device. Default value is “yes”.	hw.accelerometer
Audio recording support	Whether the device can record audio. Default value is “yes”.	hw.audioInput
Audio playback support	Whether the device can play audio. Default value is “yes”.	hw.audioOutput
SD Card support	Whether the device supports insertion/removal of virtual SD Cards. Default value is “yes”.	hw.sdCard
Cache partition support	Whether we use a /cache partition on the device. Default value is “yes”.	disk.cachePartition
Cache partition size	Default value is “66MB”.	disk.cachePartition.size

Thus according to the chart we should add “Camera” and the 5.0 megapixel camera on the Nexus One corresponds to 2592 Maximum Horizontal Camera Pixels and 1944 Maximum Vertical Camera Pixels (The exact number of pixels is a guess of mine based on the 5.0 Megapixels, but unless you’re doing some hardcore testing I think it will be fine). Set the Device RAM Size to 512 MB for the Nexus One.

Ok, that’s about it. Now click “Create AVD” and the program will appear to freeze for a while. Finally, the AVD will be created and Nexus_One_Froyo_2-2 is located in the .android\avd folder.

Andrew Parsons speaks on marketing to Uni Students

Tommy — Tue, 27 Apr 2010 10:59:34 +0000

Andrew Parsons from Microsoft gives some pointers about how to make your on-campus marketing campaign successful. Maybe google or apple should watch this and learn!

ebooks online

Tommy — Sun, 14 Mar 2010 05:03:27 +0000

A collection of possibly useful links:

www.gutenberg.net – Free, in the public domain books. Lots of older books like the Wizard of Oz and some more modern books; it’s mostly only sci-fi publishers are releasing their books into the public domain. http://worldebooklibrary.net/ also distributes these (same) books in .pdf format, but gives you the chance to pay.

Maybe you could try negotiating with one of the services for libraries, such as: http://www.overdrive.com/ or http://www.exacteditions.com/. Basically, after the institution pays, these sites generally allow the members of the institution (numbering in the hundreds of thousands) to read books.

And also on the topic of libraries, you can try a public library. Taipei library has a few different types of ebook collections: http://www.tpml.edu.tw/TaipeiPublicLibrary/index.php?subsite=english&page=english-eresource-index.php

I was also paying for questia.com but the selection is big but oriented towards nonfiction.

www.oreilly.com – It really depends on the type of books that you’re looking at. For computer/tech books, uses the epub format, which might not be so hard to use, since it’s basically just a kind of html with divisions for chapters, etc. Kate did Traditional Chinese translation for their epub reader, but for some reason they haven’t posted that version yet…

Mostly tech books: safaribooksonline.com
For kids: http://www.benchmarkeducation.com/ebookroom

The trouble is you might have problems of scale. You can pay for 10 or 100 books, but if your experiment is on free-choice, that’s not much of a choice. So that’s why I might suggest that you use something like wikipedia or a particular popular online e-magazine as the source. There’s so much to choose from and it’s free~

Unit tests in c++

Tommy — Sun, 21 Feb 2010 12:26:28 +0000

Now that I’m using c++ again, I’m getting interested in unit tests, of course. But a little research showed me that there has been some reluctance to unity tests in the community, primarily due to the lack of reflection in unmanaged code.

Since unit testing is so awesome, it hasn’t been entirely overlooked, luckily. First I found an interesting question on this at http://stackoverflow.com/questions/3159
There’s a good overview of a bunch of different tools there.

I also read a good article by Michael Feather. http://objectmentor.com/resources/ articles/TheHumbleDialogBox.pdf
He explains why we need to separate the smart objects so we can communicate with them. Cool!

I’m also downloading some unit test plugin for Visual Studio. I’ll let you know how that goes!

Unit tests in c++

Tommy — Sun, 21 Feb 2010 12:23:00 +0000

I’m also downloading some unit test plugin for Visual Studio. I’ll let you know how that goes!

My new android

Tommy — Sat, 30 Jan 2010 13:29:52 +0000

Just thought that I’d test the capabalities of this phone to post here.

This Text Is Now Writing Your Mind

Tommy — Fri, 15 Jan 2010 09:22:05 +0000

This Text Is Now Writing Your Mind

Send to:

Tommy — Sat, 09 Jan 2010 13:33:24 +0000

Using Send-to in Ubuntu is supposed to be a helpful thing. Although I prefer using the Terminal for copying files to new locations, let’s see how send to works:

First, we right click the file:

Then we see the Send To dialog box:

We select the “Removable Media”.

Select the disk we’d like to send it to:

We have the option to send it as a zipped file:

We go to the target location and see if the new file is there:

If it’s not, we can just consider what happens in the terminal if using the command “cp” which means to copy. First, I look to see what drives are available:
tommy@ubuntu:~$ ls /media cdrom cdrom1 floppy U3 System cdrom0 f2fc5429-adbc-4957-b436-f990c1cba426 floppy0 Ubuntu 9.04

Check what’s on the drive:
tommy@ubuntu:~$ ls /media/f2fc5429-adbc-4957-b436-f990c1cba426/ bin dev initrd.img media opt sbin sys var boot etc lib mnt proc selinux tmp vmlinuz cdrom home lost+found root srv usr

I want to see my new file. It’s called “new file”.
tommy@ubuntu:~$ ls Desktop Downloads Music new file~ Public Videos Documents examples.desktop new file Pictures Templates

I copy the file into the USB drive, which has a really long name.
tommy@ubuntu:~$ cp new\ file /media/f2fc5429-adbc-4957-b436-f990c1cba426/ cp: cannot create regular file `/media/f2fc5429-adbc-4957-b436-f990c1cba426/new file': Permission denied

I realize that the copy command cp doesn’t work outside the user directory. Therefore, use sudo with password.
tommy@ubuntu:~$ sudo cp new\ file /media/f2fc5429-adbc-4957-b436-f990c1cba426/ [sudo] password for tommy:

Check that the file copied:
tommy@ubuntu:~$ ls /media/f2fc5429-adbc-4957-b436-f990c1cba426/ bin dev initrd.img media opt sbin sys var boot etc lib mnt proc selinux tmp vmlinuz cdrom home lost+found new file root srv usr

yes, it did, because “new file” now exists on the drive. Wow, the terminal works but rightclick “Send to” doesn’t.