Daily Archives: 14 Apr 2013


14 Apr 2013

Since you last encountered me, I’ve been working on figuring out TUIO and Control P5, and have a few basic things working, but I still haven’t gotten two basic issues out of the way: 1) How do I make a construct that reliably holds the object IDs for the active fiducials, 2) How do I prevent more than 3 characters being selected at the same time? Both of these issues seem like they should be simple, and solved problems, but I can’t find anything useful on the internet.

In any case, check out some awesome screenshots from my recent tinkering!

Screen Shot 2013-04-15 at 12.21.01 AM

Screen Shot 2013-04-14 at 11.06.39 PM


14 Apr 2013

The goal is to ‘grow’ a mesh using DLA methods: a bunch of particles moving in a pseudo-random walk (biased to move down) fall towards a mesh.  When a particle, which has an associated radius, intersects a vertex of the mesh that vertex moves outward in the normal direction by a small amount. Normal Direction means perpendicular to the surface (this is always an approximation for a mesh)  Long edges get subdivided. Short edges get collapsed away.  The results are rather spikey.  It would be better if it was smoother. Or maybe it just needs to run longer.

Ideas for making smoother:

  1. have the neighbors of a growing vertex also grow, but by an amount proportional to the distance to the growing vertex. One could say the vertices share some nutrients in this scenario, or perhaps that a given particle is a sort of  vague approximation of where some nutrients will land.
  2. let the particles have no radius. Instead have each vertex have an associated radius (a sphere around each vertex), which captures particles.  This sphere could be at the vertex location, or offset a little ways away along the vertex normal. This sphere could be considered the ‘mouth’ of the vertex
  3. maybe let points fall on the mesh, find where those points intersect the mesh, and then grow the vertices nearby. Or perhaps vertices that share the intersected face.

Ideas for making Faster:

  1. Discretize space for moving particles about. This might require going back and forth between mesh and voxel space (discretized space is split up into ‘voxels’ – volumetric pixel)
  2. moving the spawning plane up as the mesh grows so that it can stay pretty close to the mesh
  3. more efficient testing for each particle’s relationship to the mesh (distance or something)


This one came out pretty branchy but its really jagged and the top branches get rather thin and platelike. This is why growing neighbor vertices (sharing nutrients) might be better.


14 Apr 2013

Screen Shot 2013-04-14 at 9.59.09 PM

I’ve switched focus a bit since the group discussion on project ideas.  I’m still focusing on the SDO imagery and displaying multiple layers of the sun time lapse, but I’ve decided that a more interesting approach to the project is to explore how people process different images of the sun when viewed through different eyes.  The first technical challenge to this is to create a way to view multiple Time Machine time lapses side by side.  I’ve managed to learn the Time Machine API and I’ve reworked a few things as follows:

A) Two time lapses display side-by-side at a proper size to be viewed through a stereoscope

B) Single control bar stretched beneath two time lapse windows

C) Videos synchronize on play and pause.  (Synchronization on time change or position change still results in jittery performance)

The synchronization needs a bit of work still, and then comes the time to work on the interface a bit more to support changing the layers in an intelligent and intuitive way.  I need to figure that out a bit and make some sketches.