0xtob’s coding blog

Sometimes when I added a new feature to Pocket Physics, I thought “This is actually quite fun!” In this version, I added the moving tool, and I must say: This is seriously an awful lot of fun! You can now directly interact with your sketches by grabbing and throwing objects with the stylus! Also, editing has become a lot easier because you don’t have to delete and re-draw objects to reposition them. Try it out, it’s really cool!

Get it from the project homepage!

Again, a big thank you to Erin Catto for making the amazing Box2D library!

A note on stability:
Pocket Physics uses a modified version of Box2D that uses fixed point math instead of floating point. Due to this conversion, a lot of unexpected things (spontaneous explosions, freezes, etc) can occur. I’m working on improving stability of Box2D, but it takes time to track down and fix these bugs, so please bear with me.

This might become interesting.

Big thanks to bushing, segher, tmbinc, wintermute and everyone else working hard to make Wii homebrew possible!

Version 0.4 is out and adds saving and loading! Never lose your work again, and share your creations with others!

Get it from the project homepage!

I want to highlight a really fun music application called MIDI Jammer by Andrew Buch, which uses DSMI for sending MIDI events. The touch screen is divided into horizontal/vertical bars which are mapped to notes of a scale that can be configured by the user. You can jam around just by sliding the stylus over the bars. The fun thing is that it’s pressure sensitive, so the volume depends on the pressure you apply. In another mode the program can also be used as a Kaoss Pad (which is more flexible than KaossDS). Andrew is planning on a standalone mode that uses the PSG for live chip-style jamming!

Here’s a new version with a larger drawing area, dual screen support, updated physics and more!

The top screen displays an overview and the bottom screen shows a zoomed in view.

Here’s a contraption in which a car hits some dominoes, the last domino falls on a seesaw and makes a ball fall into a shopping cart.

Get it at the project homepage!

Here’s a new release of the DS port of Box2D. Robert Kavaler helped me out a lot on this by porting the changes to the SVN version of the (still work-in-progress) Box2D 2.0 and adding a nice build system. Although this is a patch of an unstable version of Box2D it works very stable. By using the DS’s hardware division and sqrt functions I improved simulation speed. Instead of the patches library, the archive now contains a patch with instructions how to acquire and patch Box2D.

Download: box2d_svn_r80_fixed.tgz

JCRocky5 made this great ragdoll video with Pocket Physics

Pocket Physics v0.2 is out! Main new feature: Pins!

You can now play with seesaws…

cars…

and even ragdolls!

Get it at the project homepage!

Did you ever sit on the bus and think “Damn, now I could really use a program that treats my drawings as physical scenes and simulates the interaction between objects on them!” ? Well, me neither, but here’s one anyways.

You can design scenes freely by drawing things with the stylus. Things can be solid, like ramps and floors, or dynamic, like balls or boxes. Like in The Incredible Machine, you can reset the scene, change it, and start the simulation again. It’s even more fun if you have a DS Motion, which can be used to control gravity!

Here’s what it looks like:

As you can see, the main inspiration comes from Crayon Physics :)

Some implementation details for those who care: For the physics simulation I used the Box2D library by Erin Catto (DS port here). For graphics, I’m using μLibrary by Brunni, which allows for fast drawing of 2D objects using the DS’s 3D capabilities. The background image is One for SXC by Felipe Skroski. The crayon texture was made in GIMP, and the sounds were recorded on my DS with NitroTracker :)

Get it from the project homepage and tell me what you think of it in the GBADev Forum or via comments.

As you know, physics is the new 3D. So why not just ditch the 3D for the good old 2D? 2D was much cooler anyways, and a lot of games that were fun in 2D became quite annoying in 3D.

This is where Box2D comes in. It’s a very easy to use 2D physics library with a growing set of features. Box2D got a lot of attention from the game Crayon Physics that showed the potential of the library. Unfortunately, it is not perfect for the DS, because it uses floating point math, which the DS’s CPUs don’t support. So, I decided to create a DS port with fixed point math. Check it out, it’s really easy and a lot of fun!

box2d-1.4.3-ds2.tgz

Update:
The fixed point and Nintendo DS patches are now part of the official Box2D SVN! If you want to use Box2D on the DS, just check out the latest version from SVN. Also, check out my DS physics toy Pocket Physics.