zero point nine

view at full size >

Sooner than expected (thanks no doubt to my first snow storm in two years giving me all the excuse I needed to stay in all day), this version covers bullet-point 2 of the previous post:

I’m using Adobe’s Kuler service to generate the color scheme, which I find quite exciting. Because it saves this particular demo from a world of red and black — which are basically the only colors I use when left to my own devices. (Press [C] to cycle through colors) Many thanks to Aden Forshaw for the AS3/Kuler example.

Finally worth noting is that the ‘physics’ have improved a little. I was previously using vertex count as a proxy for mass. Using the volume of the axis-aligned bounding box ends up being a better way of faking it.

A demonstration of splitting a mesh in two along an arbitrary plane. With some faux-physics for added value. I was thinking about the ‘laser room scene’ in Resident Evil, LOL.

I’ve included the source code of a minimal example showing how to cut up the faces of a mesh along a plane:

PlaneSplitMinimalExample.as | compiled swf

This is the foundation for everything in this demo, and for the following ideas which I think would be nice to see executed in Flash–

Make sure to try resetting the scene, pausing (with spacebar), clicking through a mesh several times, and then unpausing..

Oh yeah, and the usual disclaimer/apologies about how much this demo hates your CPU, and how unoptimized it is (e.g., right now every face in the scene is tested against the plane with every click (ouch!)). Built with the most recent revision of Papervision 3D.

Also, apologies for the long hiatus.

UPDATE: John Lindquist has kindly pointed out there’s already a helper function in the Papervision framework for cutting meshes with planes! – MeshUtil.cutTriangleMesh().

Licensed under a Creative Commons Attribution 3.0 License.

This is a slideshow viewer, utilizing the robot arm from this previous post done with Papervision 3D. I created it on the occasion of a presentation I’m preparing for the Flash user group, San Flashcisco. In typical fashion, I’ve spent more time creating the slideshow program than preparing the presentation itself, or the slides for it. :P The slides themselves (dealing with Papervision3D) aren’t of too much value outside of the context of the presentation, but you can choose your own if you like (see below).

The program uses hotkeys only –

  [SPACE/BACKSPACE]  Next/previous slide
  [BRACKET KEYS]     Next/previous slide without transition
  [COMMA]            Zoom in and out of slide, for the fun of it

   Also:             [1/Q, 2/W, 3/E, 4/R, 5/T, 6/Y, and 7/U] - Rotate joints
                     [Z,X,C,V] - Moves robot arm to various keyframes/poses

How to use this with your own images, from the Desktop…

(more…)

Recently I’ve been thinking on ways of programmatically creating curvy and strange, organic-looking shapes in 3D. And reflecting on the fact that I can think of no particular ‘practical’ application for such an endeavor. And concluding that that’s part of what makes it interesting…

Here’s the high-level recipe:

Start with a cylinder or sphere-shaped mesh, where the vertices are evenly spaced . The vertices of the mesh can be thought of as a matrix or grid, where the left and right edges are curved 360 degrees until they meet.

Take an interesting bitmap with varying light and dark areas, whose height and width match the number of rows and columns in the mesh.

Use brightness (or some other color-derived property) from the pixels of the bitmap as a multiplier value to dictate the distance of the corresponding vertices from the z-axis (center) of the shape.

That’s basically it. In Flash, the built-in BitmapData.perlinNoise method is perfect for generating interesting gradients. The kicker is that the last parameter of the method allows you to change the x & y offset for each ‘octave’ (think semi-transparent layer), allowing for gradual, random-looking changes over time.

So on each update, change the offset of each octave of the perlin noise image and recalculate the vertices accordingly. The behavior and properties of Perlin noise does the rest.

Licensed under a Creative Commons Attribution 3.0 License.

I’ve been getting comfortable with Processing over the last few days by experimenting with what else but … particles. The three-dimensional patterns that emerge by moving the sliders to change the internal parameters can be quite complex and unexpected, and sometimes strange attractor-like.

The algorithm governing the particle motion is very straightforward. New particles are created with a starting orientation which rotates linearly on 2 axes over time. On each frame, a given amount of x, y, and z rotation is added to each particle and then the particle is translated according to its orientation by a steadily increasing distance.

Click on the buttons in the bottom right corner to change the order that the x, y, and z rotations are applied (which creates very different results from each other). The 3 sliders on top-left control the amount of rotation added per frame; the two sliders in the middle control the rate of ’spin’ for the initial orientation of new particles; and the slider on the right controls the ’speed’ that particles move away from the point of origin.

Licensed under a Creative Commons Attribution 3.0 License.

Kind-of just for the hell of it as much as for any potential use value, I’ve converted all my notes related to programming, Flash, etc. – which used to live in various text files as various versions on various computers – into a wiki format. And have made it publicly viewable. Because, I figure, why not?

Much thanks to Adam Smith for the idea. Have fun in L.A.

Webcam DVR has been updated for compatibility with the release version of Adobe AIR. I didn’t introduce any serious changes with this version. I don’t have the time to self-QA this in the way it deserves, so if you run across any bugs – big or small – please let me know!

Download (Adobe AIR file, 291K)

Requires the Adobe AIR runtime.

See the original post for more info and usage notes.

Apologies for the cobwebs on this site. I’ve been pretty busy with .. work.

A forward kinematics experiment using Papervision3D v2.0 alpha and a Collada 3D model of a robotic arm.

Hope you enjoy it.

I don’t want to release any source from this yet, as I want to do some more work on it, relating to the following items…

(more…)

Just wanted to let anyone in or around the Bay Area know that there’s going to be a Papervision3D training with John Grden on the weekend of February 3-4 in San Francisco. It’s being held at EVB, which is where I work.

Here’s the link: http://pv3d.eventbrite.com/

If you’re going, look me up, as I’ll be there…

I drew up this example a few weeks ago to learn about the new features in Papervision 2.0 alpha. If you’re thinking of looking into the new version, then hopefully you’ll find the supplied source code below of some use. I used the code from this screencast on unitzeroone.com as a starting point.

The source code has example usage of the following things…

(more…)