Now that Vrui is working on the HTC Vive (at least until the next SteamVR update breaks ABI again), I can finally go back and give Vrui-based applications some tender loving care. First up is 3D Visualizer, an application to visualize and, more importantly, visually analyze three-dimensional volumetric data sets (see Figure 1).
Figure 1: Analyzing a CAT scan with 3D Visualizer on the HTC Vive. Cat included.
I wasn’t able to talk about this before, but now I guess the cat’s out of the bag. About two years ago, we helped a team of archaeologists and filmmakers to visualize a very large high-resolution aerial LiDAR scan of a chunk of dense Honduran rain forest in the CAVE. Early analyses of the scan had found evidence of ruins hidden under the foliage, and using LiDAR Viewer in the CAVE, we were able to get a closer look. The team recently mounted an expedition, and found untouched remains of not one, but two lost cities in the jungle. Read more about it at National Geographic and The Guardian. I want to say something cool and Indiana Jones-like right now, but I won’t.
Figure 1: A “were-jaguar” effigy, likely representing a combination of a human and spirit animal, is part of a still-buried ceremonial seat, or metate, one of many artifacts discovered in a cache in ruins deep in the Honduran jungle. Photograph by Dave Yoder, National Geographic. Full-resolution image at National Geographic.
Can an application like that be done for Mars? Do we have enough data, and are the data publicly available? The answers are “yes, alreadydone,” “kinda,” and “yes, but,” respectively.
As of my last checking, there are two main sources of topography data for Mars. The older source is an orbital laser range survey done by the Mars Orbiter Laser Altimeter (MOLA). This is essentially a planetary LiDAR scan, and can be visualized using LiDAR Viewer. The two pictures I mention above are these (Figures 1 and 2):
Figure 1: Global visualization of Mars topography using the MOLA data set, rendered using LiDAR Viewer. Vertical scale is 5:1.
Figure 2: Close-up of global Mars topography data set (centered on the canals), showing individual laser returns as grey dots. The scan lines corresponding to individual orbital periods can clearly be identified. Vertical scale is 5:1.
Figure 1: Screenshot from video showing VR ProtoShop run simultaneously in a 3D environment created by an Oculus Rift and a Razer Hydra, and in a 2D environment using mouse and keyboard, brought into the 3D environment via the VNC remote desktop protocol.
There have been several discussions on the Oculus subreddit recently about how to integrate 2D desktops or 2D applications with 3D VR environments; for example, how to check your Facebook status while playing a game in the Oculus Rift without having to take off the headset.
This is just one aspect of the larger issue of integrating 2D and 3D applications, and it reminded me that it was about time to revive the old VR VNC client that Ed Puckett, an external contractor, had developed for the CAVE a long time ago. There have been several important changes in Vrui since the VNC client was written, especially in how Vrui handles text input, which means that a completely rewritten client could use the new Vrui APIs instead of having to implement everything ad-hoc.
Here is a video showing the new VNC client in action, embedded into LiDAR Viewer and displayed in a desktop VR environment using an Oculus Rift HMD, mouse and keyboard, and a Razer Hydra 6-DOF input device:
I always love it when an image I made, or a photograph I took, pops up in an unexpected context. I have recently been drafted for a campus committee, the Campus Council for Information Technology, and the guest speaker in today’s meeting, Patrice Koehl, did a presentation on Big Data, Data Analytics, the need for data centers, the lack of collaboration between computer scientists and other scientists, etc. Among his slides was this one (apologies for the lousy quality; I took the picture with my laptop’s built-in camera):
Figure 1: Snapshot from today’s CCFIT meeting, showing Patrice Koehl, one of his slides, and one of my pictures on one of his slides (indicated by red frame).
I thought I did a really good job with the color map, given that that’s not normally my forte. The icy blue — dark blue gradient nicely brings out the fractures in the crust, and the heavy element inclusions stand out prominently in gold (Blue and gold? UC Davis? Get it?). You can watch the full video on YouTube. I’d link to Qing-zhu’s own copy of the video, but it has cooties, I mean ads on it, eww.
And as can be seen in a full-page ad on page 31 of the same issue of Microscopy Today, apparently my picture — no doubt by virtue of the 3D meteorite fragment scan shown in it — was one of the winners in a “coolest thing you’ve never seen” contest held by the company who made the X-ray CT scanner. My little picture is Miss September 2013. Hooray, I guess?