Thoracosaurus neocesariensis

Thoracosaurus neocesariensis

Wednesday, November 18, 2009

More Scan Stitching

I just spent a lot of time getting together various bones. Below is a sample image (click to enlarge). I put together the humerus, femur, a couple "scutes," a tooth and started on what we have of the skull. The skull is in five different pieces. It is currently cleaned up but just needs to be put together. After the skull and jaw are together, it's nothing but vertebrae left for the scan stitching.

I was able to vastly improve my workflow with the help of a "Global Registration" option in Geomagic, which allows me not only to speed up the process of stitching, but also helps create more accurate piecing, since it is not done by the human eye. As long as the pieces are in close approximate positions (done manually), the algorithm is able to detect the topology and adjust itself for a more perfect fit.

Despite this discovery, it took a little bit of playing and experimenting to figure out how it works. There were lots of little strange bugs that arose when using the program that slowed down my newfound speed, but each day I am getting better at this.

I've also started reading my que of papers on Crocodylians by Christopher Brochu. This week is: "Crocodylian Snouts in Space and Time: Phylogenetic Approaches Toward Adaptive Radiation" (2001). This will be helpful when reconstructing the missing snout of our Thoracosaurus.

I also spent time on looking up reference imagery of marine forests, mangrove swamps, etc. to influence the revision of my environmental plan. Stay tuned for some concept art on that, as well as some beginnings of possible storyboards of the animation.

Tuesday, November 3, 2009

Proxy Environment Startup

I blocked out an environment to help me start to visualize the final result for when I storyboard... Here's the super simple mangrove swamp, complete with trees, bushes, and even a proxy thoracosaurus...

Scan Stitching Round 1

itching of the scanned cervical vertebrae of Thoracosaurus neocesariensis has begun. C1-C4 have been put together. They each consisted of about 8-12 scans (for different angles) which had to be combined. It is a laborious process, and I have to say I much prefer piecing in the physical world with glue than in the digital world. This is mostly because of how slow it gets with the amount of geometry that Geomagic Studio 11 is trying to handle. Don't get me wrong, it's so much nicer than the old software we had, but it still starts to get clunky. Also, in the physical world you can feel when things click into place a lot of times, letting you know that that's exactly how the piece fits. In the digital world it's all visual, which brings me to another challenge. With the virtual scans, the points that are further away from the focal point of the scanner's lens become rougher and less accurate due to the focal distance of the lens. This means that using points closer to the edges of the scans as registration points becomes more and more difficult to do. Also, there's the issue of the complexity of the fossils, with many crevices that it is difficult to gather sufficient data from with the scanner. Geomagic has ways to fill holes, which works pretty well a lot of the time, but also introduces a degree of innaccuracy. Some of the more complex objects, also have larger holes, which might call for a second scanning session, although the same problems will just arise again. We may be able to infer the missing parts through hand modeling with reference photographs, and looking at the other scanned bones of the same type for reference as well.