Past in Pixels started as a pilot study looking to create heritage experiences and educational products for the general public, something that was both engaging and archaeologically accurate. We wanted to start first with a reconstruction of a site, something that was intensely studied, relatively well understood, with a robust publication list and preferably with lots of artististic interpretations already available. We were looking for a proof of concept, something that we could test our proposed methodology on, where we could work out any difficulties on a small scale.
Cahokia is a large pre-Columbian Native American city that is located in present day Illinois, near the border of Missouri, Just north of present day St. Louis. This area has been a hotbed of human activity for centuries of North American history. The site lies near a very important meeting of several major rivers, the Mississippi, the Missouri, and the Illinois Rivers. Waterways such as this not only provided an easy source of food, it also provided a way to transport both people and goods, and served as an important vein for the north and the north west of the North American continent (Fowler 1997).
At its height Cahokia would have covered about 16 km² and includes about 120 manmade earthen mounds with vary wildly in shape and function (NPS 1982). It was built by the Mississippian culture, and is generally considered to be the largest, most complex archaeology site north of Mexico. It was designated a UNESCO world heritage site in 1982 (Ibid).
This site has been studied and talked about since the mid-19th century, and hundreds of articles and books have been written about the site and the Mississippian culture and it is often called America’s lost city. It has been the subject of several documentaries, and remains to this day as a national monument that anyone can visit (visitor information can be found at cahokiamounds.org) As one of the most famous archaeological sites in America, and due to the amount of research undertaken on the site, it is an almost perfect fit for our first case study in site creation for Past in Pixels.
The archaeologists were excited by this site, and the visualisation team were in awe of its size and history. With some help from the Illinois Geological Society we were able to acquire a LiDAR survey undertaken by the History Channel of the site in 2013 for a documentary. This data was freely available to the public, and we were able to use this data as the basis of our landscape creation. The site however is huge, and we were overwhelmed by the amount of mounds and information. Our study was small, so we decided to focus on only building one mound in great detail, the iconic Monk's Mound. Not to say we did not build other mounds, but we wanted to limit player movement and focus all of our attention to detail to one part of the site, due to both time and resource constraints. We were looking to create a proof of concept, not necessarily a full prototype yet.
Our archaeologists processed the LiDAR data in a GIS program and were able to extract something called a TIN mesh (triangulated irregular network), basically a 3D surface of the archaeological site, made entirely of triangles. We put this into Unreal Engine 4 and were able to sculpt the landscape around it. Of course the site today is eroded, and has collapsed a few times in its history, so we also used published measurements of the mound terraces, and merged this information together. We wanted to show the mound after some use, in its mid life, fresh after a collapse. We wanted to give it some life, a worn in feel. On top of the raw data provided to us, we also did an extensive literature review, looked at comparative sites, and contemporary art work to help build up the reconstruction. Our aim was to create a site that people could walk around in, interact with NPCs and learn about the Bottom Mississippian culture. Work on this was put on hiatus as other projects came in. The landscape and environment are built, a few assets, but no NPCs have been created yet. Most of the heavy lifting has been done on this project, it just needs some time and love to polish it off. Below is a video of a scene that we created for Cahokia.
For more historical information about the Cahokia Mounds please check out Mink 1992, Iseminger 2010, and Pauketat 2009, details of which are located in the bibliography below.
Fowler, Melvin L. (1997). The Cahokia Atlas: A Historical Atlas of Cahokia Archaeology. 2nd ed. Urbana: Illinois Transportation Archaeological Research Program, University of Illinois.
Hodges, Glenn (2014). Study Says Cahokia, America's First City, Was a Melting Pot [online]. Available at: http://news.nationalgeographic.com/news/2014/03/140307-cahokia-native-american-archaeology-mississippian/ Accessed 09 June 2017.
Iseminger, William (2010). Cahokia Mounds: America’s First City. 3rd ed. The History Press
Mink, Claudia (1992). Cahokia City of the Sun. 2nd ed. Collinsville: Cahokia Mounds Museum Society.
NPS (1982). World Heritage List Nomination Submitted by the United States of America: Cahokia Mound State Historic Site [online]. WHC Nomination Documentation. Available at: https://www.nps.gov/oia/topics/worldheritage/Nominations%20pdf/CAHOKIA.pdf Accessed 09 June 2017.
Pauketat, Timothy R. (2009). Cakohia: Ancient America’s Great City on the Mississippi. London: Penguin.