Thoracosaurus neocesariensis

Thoracosaurus neocesariensis

Monday, February 15, 2010

Poly Counting

 (For all images below, feel free to click on them to view the full sizes)

I. Poly Counts

This Past week was spent with a lot of time looking at ways to reduce polygon counts of the fossil scans in order to make them useable for animation without crashing every program known to man. The full resolution scans are priceless for the scientific community, but are very impractical in an animation production environment. I was worried I would have to block model every bone to create low resolution versions to use, but luckily, there is a tool inside the scanning software (Geomagic Studio) that allows a user to specify the number of polygons to reduce the geometry to. Based on past characters I have built, I estimated that around 10,000 triangular faces is a good number to use to keep a lot of the detail while reducing the number of faces significantly. The original scans were coming in around 400,000 reducing to 10,000 is an extremely significant reduction (About 1% of the poly count of the original) but doesn't take away too much of the detail.




After I created a series of lower resolution versions of each bone, (10K tris, 5K tris, and 2K tris) I started to put the skeleton together. I used the procedural nature of Side Effects Software's Houdini in order to allow me to quickly position the low resolution versions, and create a switch that automatically swaps out the geometry for higher resolution versions. I will soon be looking into creating some sort of script that allows me to swap the 10K resolution bones to the full resolution bones at render time, so that the computer doesn't ever have to display them in the view port, which crashes the program every time.


...and just for kicks, here are some other views of the 10K resolution:


 I've also done some more R&D for muscle systems and for environment development....more on that to come soon. I have gone through the whole pipeline for Maya muscles a couple times to familiarize myself with that, and I have been putting myself through a crash course in Real Flow for water dynamics. Stay tuned for updates on that.

On a side note, in my continued research for croc anatomy, I came across the relatively recent British television series, titled Inside Nature's Giants, where a team of scientists dissect a different large/specialized animal in each episode. One episode happened to be about the Nile Crocodile! This was very informative in not only showing the musculature and other structures underneath, but also putting the anatomy in a physiological and evolutionary context. It was extremely effective and I learned a lot very quickly. I strongly recommend it to anyone who's interested in this stuff. The other episodes were pretty great too (I especially liked the one about the giraffe).

Wednesday, February 3, 2010

Knee Deep in Literature

So lately I've been delving deeply into the Literature, trying to resolve some of the issues with the missing skeleton parts.  To get my feet wet, I read through the skeletal portion of Robert Chiasson's Laboratory Anatomy of the Alligator. After that it was an in depth looks at some Christopher Brochu Papers, including some about crocodylian phylogeny issues, and some papers about Eothoracosaurus and Eosuchus. Unfortunately I was having trouble finding any papers dedicated to Thoracosaurus neocesariensis in particular. Every lead I had pointed back to a Kenneth Carpenter paper on the species, but I have been having trouble locating a copy. That being said, Brochu describes the same specimen that Carpenter does, and argues that it is in fact not actually Thoracosaurus, and distinguishes it as Eothoracosaurus. In these comparisions I was able to find out some descriptions of Thoracosaurus, which was very helpful.

For what I cannot find on Thoracosaurs neocesariensis I will have to extrapolate from the other "thoracosaurs" (Eothoracosaurus, Thoracosaurus, Thecochompsoides) as well as the modern gavialis.

I then did some reading up on Gharial descriptions and behavior. I found some great information on their hunting behavior in particular, which was very interesting. I am very close to being able to draft up a proposed animatic based on the behavior of these large fish-eating crocodylians. I have also been looking for video documentaries on gharials to watch and study, so I can see some of this described behavior in action. BBC motion gallery is a great reference but only goes so far.

I am now working on a large variety of things. I need to jump head first into the muscle systems. But more importantly I need to figure out the best way to create low resolution "proxy" bones to act as stand-ins for the high resolution scans, so that I can actually rig and animate them. That's the next thing on my list. I may have to hand model some simple proxies, and the scanning software (Geomagic Studio) may be able to do a lot of the heavy lifting for me. Then I'll have to write some sort of script that substitutes the proxies with the full quality at render time... Lots to do lots to do! Stay tuned for more updates. Once I figure out this pipeline, I promise I'll post a rendered image of the full digitized skeleton.

Literature Read this Week:

Brochu, C. A. (2006) Osteology and phylogenetic significance of Eosuchus minor (Marsh, 1870) new combination, a longirostrine crocodylian from the Late Paleocene of North America. Journal of Paleontology 80(1):162-186.

Brochu, C.A. 2004. A new Late Cretaceous gavialoid crocodylian fromeastern North America and the phylogenetic relationships of Thoracosaurs.

Brochu, C. A. 2001. Crocodylian snouts in space and time: phylogenetic approaches toward adaptative radiation. American Zoologist 41:564–585. 

A study of fossil vertebrate types in the Academy of Natural Sciences of Philadelphia: taxonomic, systematic, and historical perspectives Issue 16 of Special Publication Series, Academy of Natural Sciences (Philadelphia, Pa.) By Earle E. Spamer, Edward Daeschler, L. Gay Vostreys-Shapiro. Academy of Natural Sciences, 1995

Thorbjarnarson, John B. 1990. Notes on the Feeding Behavior of the Gharial (Gavialis gangeticus) under Semi-Natural Conditions. Journal of Herpetology 24: 99-100.
Whitaker, Romulus. 2007. The Gharial: Going Extinct Again. Iguana 14: 24-33

* The list on the right hand side is what is next in que for the research aspect of the project. If anyone has any suggestions of papers to read, please let me know and I'll incorporate it into my que!

Oh yes, and I appologize for the lack of pictures.