Code

US Droid + Root = Multitouch?

4volt — Mon, 16 Nov 2009 19:05:47 GMT

After having the new Motorola Droid for about a week, I've been very impressed with it’s features, usability, and experience.

Previously I was using a windows mobile phone, and as far as usability goes, Android is leaps and bounds better then even the latest (6.5) version of Windows Mobile.

Although, when I show my phone to an iPhone users, they generally complain about the lack of multitouch, especially in the web browser, and the on-screen keyboard. I think that feature alone will end up being a major sticking point when people talk about switching from the iPhone to the Droid.

As you may or may not know, the US version of the droid does not have multitouch in the apps that Google/Verizon distributes with the phone (including the browser and keyboard). The speculated reason why multitouch is not enabled in the US Droid is that apple’s patent on multi-touch that is not valid in Europe.

After some little research there is a app (PicSay) in the Google Marketplace that takes advantage of multitouch on a stock, unmodified US Droid for zooming pictures. So, it is true that multi-touch is supported and enabled in hardware, but not taken advantage in software.

My theory: multitouch is only disabled by configuration in the Android OS, and if one were able to root the US Droid they could re-enable multitouch with some simple configuration changes.

This assumes that Google uses the same distribution of apps for both US and Europe. Although, if that is not the case, one could alternatively copy the European ROM (or apps) to the US phone with a minimum of fuss.

I'm keeping my two fingers crossed for a root exploit in the near future, and the possibility of multitouch. At this point I think it’s probably too late in the game for Google/Verizon to change their minds about multitouch, though I hope they do. It would make the Droid a stronger competitor with the iPhone.

Also, Android Marketplace developers should be, or may already be working on a multitouch version of the on screen keyboard. An independent app could take advantage of multitouch, and wouldn’t require rooting the phone, so you could type with two fingers.

Update 12-08-2009:
Dolphin (A 3rd party web browser) that you can get in the marketplace supports multi-touch. Search for it in the marketplace, it's free.

Update 12-10-2009:
A root exploit for android 2.0 on the droid was found and after reading into it, it looks like the apps in question were complied without the multi-touch libraries. It should be a matter of re-compiling or coping multi-touch binaries.

Since dolphin exits, I think if someone were to make a multi-touch on-screen keyboard, people would not have much to complain about .

Update 01-29-2010:
This article is now out of date, but most people are just just downloading multi-touch apps and calling it good, though there are also some mutli-touch + root modifications you can do to the droid and nexus.

New Generative Art – Missile Cloud

4volt — Wed, 29 Jul 2009 07:06:12 GMT

Lately I’ve been playing around with generative art for framing and hanging, this is a collection from some code I wrote in Context Free. I’ve also recently discovered the function to render at high resolutions and really adds another dimension of detail in this kind of recursive art.

The frames you see here are cropped sections of one of the renders I found interesting.

If you want to explore one of the 5000x3500px high-res frames, it’s here: Missile Cloud 8 – VBX (7mb). I also have a 10k pixel, 22mb version, if anyone is interested I’ll post it here.

The Context Free code is here: Missile Cloud (CFDG).

Papercraft Folded Box Generator

4volt — Wed, 15 Apr 2009 17:59:48 GMT

Zignig from Thingiverse posted a python script called "Parametric Papercraft" that will draw boxes of any size based on my folded box design. It’s a cool idea that I highly recommend checking out.

Generative Art: Context Free

4volt — Sat, 07 Mar 2009 21:10:13 GMT

I’ve been playing around with Context Free lately, it’s a 2D generative art program, meaning you can create art from code. Here’s the code for the above images:

   1:  startshape SPIKES

2:

   3:  rule CENTER {

   4:      10* {r 36} SPIKE { y 25}

   5:  }

6:

   7:  rule SPIKES {

   8:      4* {r 90} SPIKE {}

   9:  }

10:

  11:  rule SPIKE {

  12:      LSPIKE {}

  13:  }

  14:  rule SPIKE {

  15:      LSPIKE { flip 90 }

  16:  }

  17:  rule BLOB {

18:

  19:  }

  20:  rule LSPIKE {

  21:      SQUARE {}

  22:      LSPIKE { y 3 s 0.985 r 5}

  23:  }

  24:  rule LSPIKE 0.01 {

  25:      SPIKE { r 90 }

  26:      SPIKE { r -90 }

  27:      LSPIKE { y 0.98 s 0.98 r 5}

  28:  }

There’s a lot of cool stuff you can do with Context Free, I’m looking forward to spending some more time with it.

Logging into TurboGears with Flex

4volt — Sat, 14 Feb 2009 10:01:54 GMT

I spent quite a bit of time today getting a Adobe Flex application to login into a TurboGears site and I couldn’t find any good articles on how to get it to work correctly, after quite a bit of trial and error I was able to figure it out. Here’s quick post on my findings.

Form Fields

The main trick is to get the POST form parameters correct. The default TurboGears “identity.form” parameters in your app.cfg are:

identity.form.user_name="user_name" identity.form.password="password" identity.form.submit="login"

To mimic those POST fields in Flex here’s what the mx:HTTPService would look like:

    <mx:HTTPService id="tg_login" method="POST" url="http://localhost:8080/" 
        result="handleResult(event)" fault="handleFault(event)" resultFormat="text">
    
        <mx:request xmlns="">
            <user_name>{username.text}</user_name>
            <password>{password.text}</password>
            <login>Submit</login>
        </mx:request>
    </mx:HTTPService>

Crossdomain.xml

One other issue you may come across while testing on your local computer is Flex trying to read the crossdomain.xml file.

Usually this file restricts what flash applications can post to your domain. That is a problem when testing since your Flex file is probably not hosted in your TurboGears project. (you would have to explicitly add it as a static file in order for it to be served)

To avoid this problem you can create this crossdomain.xml file to allow access from all domains. Put the file in your TurboGears project directory under the \static\ folder.

<?xml version="1.0"?>
<cross-domain-policy>
  <allow-access-from domain="*" />
</cross-domain-policy>

To get that file hosted at the root of your site, you’ll need to add a static file entry in your app.cfg to include something that looks like this:

[/crossdomain.xml]
static_filter.on = True
static_filter.file = "%(package_dir)s/static/crossdomain.xml"

Technically you could host your flex application file(s) in this same way, but eclipse would still launch the flex file from the wrong location when you compile/test.

Other Notes

Once you’ve logged in to TurboGears with Flex, you should be able to access any “@identity.require” restricted data in from TurboGears in Flex.

When you are done with your development cycle and make your site public, you may want to remove crossdomain.xml from your site. Although, this only restricts clients that use the “honor system” and check for this file. If you want to truly restrict cross site scripting you should implement something on the backend.

You can download the Flex Source here:

Flex-to-TurboGearsLogin.zip

Flex LS, Spark Competition, and .Net Micro

4volt — Sat, 10 Jan 2009 07:26:24 GMT

I recently created a entry for the Spark Competition, go check it out and rate it highly. There’s 188 entries and the top 50 win a VIA Artigo Pico-ITX system which I’ve been excited to see since it’s release. I wrote a blog entry about it back in December.

The Spark Competition is for Microsoft's new embedded development environment focused on the new .Net Micro framework.

Microsoft's new framework is for lower-end microprocessors. While it is a Microsoft product it has some very interesting features like higher-level access to networking, interface, and data libraries. There are already some other competitors in this market, like the Linux based gumstix.

The .NET Micro Framework brings a rich, managed-code environment to smaller, less expensive, and more resource-constrained devices. Requiring only a few hundred kilobytes of RAM and an inexpensive processor, the .NET Micro Framework was built from the ground up to let you build applications using familiar Visual Studio development tools.

The ARTiGO Pico-ITX is probably over powered for the mid-range embedded market, I’ve seen some cool things made with the .net micro framework on much more modest hardware, it does not require windows CE.

In this video someone uses a USB(!) joystick to control a robot arm, he states the code only took a couple hours to write with the Micro environment.

I don’t think the Micro environment is a perfect fit for all embedded projects, and I haven’t been able to find the licensing cost, but I doubt it’s free. On the other hand it does provide a lot of easy higher level libraries that are sure to cut down on development time.

I’m interested in the platform purely because I already know the .net framework and I find it a good tool for rapid development of programs. My PSCombine program is written in vb.net 2.0.

PSCombine 1.5.0

4volt — Wed, 31 Dec 2008 05:33:36 GMT

I’ve just released version 1.5 of the PSCombine program. I’ve put quite a bit of time and effort into it the last few days trying to make it more flexible, and easier to use.

Head over to 4volt.com/projects/PSCombine/ to download the new version.

If you enjoy PSCombine, you can always donate, or just drop me a note.

Here’s a quick rundown on the new features:

Live View
When you are actively generating images you can use the “Live View” tab to view the images that Photoshop writes immediately after they are finished. So you can view your last image while your next one is being generated.

Issue Fixes
Fixed issue when loading a small set of images

Updates to logging system
Blending modes are now listed by name instead of ID
A benchmarking text tells you on average how long each combination takes

Advanced Settings

Blending Table
Allows you to change the minimum and maximum opacity for each blending mode, you can also disable blending modes you don’t like. Changes to the blending table take effect immediately, so you can tweak your settings while you are generating random images.
The Filters Table
Allows you to individually control which filters are used. There is also a reference table that shows on average how long each filter takes to run, witch may be useful for eliminating filters that take too much time. Changes to this table will also take effect immediately.
Allowed File Types
You may add and remove which types of files Photoshop attempts to combine, these types can be any that Photoshop understands.
Keep PSCombine on top
Keeps the PSCombine program on top of all other programs, this might be useful in conjunction with the “Live View” option.
Check for updates
Automatically checks if there are updates to the program are available on the site, and provides a link to the updated installer

PSCombine: Computer Assisted Art

4volt — Thu, 25 Dec 2008 13:54:39 GMT

I've posted the first version of my image randomizer program, I like to think of it as "Computer Assisted Art".

http://4volt.com/projects/PSCombine/

If you have any issues installing or using the program, email me, or post a message here.

Update: I've released version 1.0.4 that solves some incompatibility issues with Photoshop CS3. If you previously were having issues and were running CS3, download and install 1.0.4.

PSCombine: Computer Assisted Art

4volt — Sun, 21 Dec 2008 03:29:27 GMT

I’ve written a program that randomly selects photos from my collection and then combines them with a random opacity and blending mode. Generally, I generate 5,000 random combinations then manually sort though them and select my favorites. About 1 in 150 make the cut.

The following photos were randomly combined and mixed to create interesting new art. I like to think of this as "Computer Assisted Art".

I’ve published my most recent gallery here: 4volt.com/art/, the images in this post are from there, as well as part of my ImageBook 2008 printed book (also available as PDF) that I'm giving away as a contest this week, all you have to do to enter is leave a comment.

I've posted the PSRandom program, you'll need: Windows, Photoshop CS3 or CS4, and .NET. Give it a try and see what you think. http://4volt.com/projects/PSCombine/.

Genetic Algorithms

4volt — Tue, 09 Dec 2008 06:47:26 GMT

I came across this flash based genetic algorithm on Hack A Day.

If you are unfamiliar with genetic programming, the concept is for a program to "evolve" a solution to a given problem. A random population of candidates is generated and each is scored against each other and the fittest survive to the next generation where they are again randomly modified. With enough time and a good scoring system you can evolve a solution, this little flash app perfectly illustrates the concept.

In this instance flash tries to evolve a car where the red dots (passengers) are protected from the bumpy road. The score is based on how long the passengers survive without touching the bumpy road.

I find this field of programming extremely interesting. The kinds of problems that can be solved with this approach is potentially unlimited. Specifically, I would love to see more projects combining genetic algorithms with robotic control systems which would replace the tedious motion routines. Imagine a genetically programmed robot that could learn to move for itself with any hardware while keeping itself charged and preforming tasks.