Welcome to 3D Visualization and the Geowall Christian Educators Annual Fall Conference October 2005 The King’s University College, Edmonton Dr. Brian Martin Dr. Peter Mahaffy The King’s Centre for Visualization in Science

Workshop Goals… Provide you with sufficient technical understanding to set up your own Geowall Provide you with insights into presently available software options to use with Geowall Assist you in applying Geowall technology to your visualization interests Work collectively on understanding the educational application of Geowall

Refresher course on polarized light… Plane polarized light – what is it? Simple (and fun!) demos with polarized light  Scotch  Plastics  De-polarizers Tape!

I. Geowall – Technical Considerations Uses 2-matched DLP projectors (“left” & “right”) each outputting a plane polarized image rotated 90 0 wrt the other. Screen is “daylite” type – polarization preserving Eyeglasses “decode” left and right eye information – your brain does the rest!

Geowall – Technical Considerations Left-channel imageRight-channel image Left channel image is projected through the left channel DLP projector and is plane- polarized as shown Right channel image is projected through the right channel DLP projector and is plane- polarized as shown

Geowall – Technical Considerations Projectors are stacked vertically with 3 rotational and translational degrees- of-freedom Computer should be equipped with a video board capable of running 2 monitors Passive stereo – image “stacking” Crude alignment can be achieved using separate monitor windows from each projector

Geowall – Technical Considerations Left and Right channel polaroids are placed in front of the lens – avoid touching the lenses as conducted heat will quickly (< 1 hour) degrade filters Final alignment achieved by using stereoviewer and the Geowall alignment image Not quite!BetterGood (not perfect)! Congratulations – you are ready for stereo projection! for stereo projection!

II. Software – Creating Stereo Images Two parts:  Creating or capturing L and R channel images  Combining L and R channel images.

More on Creating Stereo Images Digital Camera  Two images contain all of the stereo information needed for your brain to produce a stereo pair Translate camera L to R

More on Creating Stereo Images 3D Image rendering software  Blender – freeware (outstanding package but steep learning curve)  Bryce (more accessible but not free) Either offset “camera” or scene and render both L and R channel images.

Combining Left and Right Channels “Do-it-yourself”:  GIMP (freeware – excellent!)  Fireworks, Photoshop etc Stereo Image Software  Pokescope (low cost < $30USD)

III. Free Software that Supports Stereo Projection Chemistry/Biology:  JMOL  Pymol  VMD  Protein Explorer Physics/Astronomy  VPython  Astrowall suite  Wallview

IV. Using 3D Projection to Enhance Student Understanding Astronomy:  Understanding phases, eclipses Physics  Magnetic fields around wires Organic Chemistry  Stereo chemistry Biochemistry  DNA, protein structure, etc

from visual import * #simple program to illustrate lunar nodes and eclipse conditions #In this example an eclipse is possible - the line of nodes points at the sun scene.stereo='passive' scene.stereodepth = 1 scene.ambient = scene.lights = [vector(1,0,0)] scene.ambient=0.1 orb1=ring(pos=(1,1,1), axis=(0,1,0), radius=50, thickness=0.2, color = color.red) orb2=ring(pos=(1,1,1), axis=(0,1,0.2), radius=50, thickness=0.2) earth = sphere(pos=(1,1,1), radius=5, color=color.blue) #sun = sphere(pos=(500,0,1), radius=15, color = color.yellow) lineofnodes = cylinder(pos=(-50,1,1), axis=(100,0,0), color=color.yellow, radius =0.4) moon = sphere(pos=(50,1,1), radius = 2) angle = 0 delta = 2e-2 while 1: rate(10) angle = delta moon.rotate(angle=angle, axis=(0,1,0), origin=(1,1,1)) #lineofnodes.rotate(angle=angle/100, axis=(0,1,0), origin=(1,1,1)) Example using VPython …easy as this!

Resources… Geowall Site: Vpython: VMD: Protein Explorer: Gimp: Blender: Contacts:  Paul Geowall  Brian Martin