ITR: Graphical Navigation of the Earth in Space and Time

关于考古学和相关学科如古生物学、地质学和古水文学的在线数据的可用性正在出现爆炸式增长。其中大部分是几何信息，要么是从现实世界扫描出来的，要么是手工建模的。我们的研究旨在利用计算机图形学的各种工具，以自然的方式访问这些数据。我们特别感兴趣的是开发新的方法来展示文化文物如何随时间和空间而变化。最终，我们设想了一个与地球相关的数据的空间/时间图形浏览器。与假设的systemA用户的浏览器的会话显示犹他大学在盐湖城的视图，大盐湖在地平线上可见。这些图像具有“建筑演示图形”的笔墨和水彩风格，仅用几笔就能显示细节和纹理，大多数颜色都是柔和的，以突出线条。这与大多数手册和教科书中使用的样式相同。用户首先在渲染的城市上空移动，俯视熙熙攘攘的人群和交通。一个特殊的建筑吸引了用户的眼球。用户点击鼠标，网页浏览器就会显示有关该建筑的已知信息，比如它建于1870年。用户将时间调整回1870年。在30秒的过程中（基于用户的偏好设置和启发式），相邻的建筑物来来去去，一个电车系统在建筑物前面出现和消失。用户现在是在1870年，对西边的湖有更清晰的看法。用户移动到湖边，可以看到流动的水和少量的人类活动。用户现在更积极地回到公元前9000年，看着湖岸随着水位的涨落而剧烈波动。现在，用户要求系统“标记”数据库中未合成数据密度高的区域。一面旗帜出现在湖的西面。用户放大到这里，看到两个洞穴。点击洞穴会打开一个浏览器窗口，显示这些洞穴是犹他州已知最古老的居住地，古印第安人在这里居住了几千年。玩家进入危险洞穴，看到一群古印第安人在火上准备食物。用户现在选择“不确定性渲染”。在这里，数据库中以高置信度存储的对象用干净的线条和详细的纹理渲染。低置信度存储的对象用粗略的线条绘制，没有颜色。例如，洞口附近的岩画仍然存在，因此具有很高的可信度。洞穴后面的岩画，如果存在的话，已经被岩石坠落和侵蚀破坏了。它们是考古学家在其他遗址的基础上推测出来的，因此可信度很低。请注意，该系统仅访问考古数据。更复杂的考古用途将由其他程序完成，正如当前的Web不用于一般数据操作一样。用户现在退出洞穴，并询问洞穴附近最近的过去和未来的重大事件。在未来，展示的是公元200年左右农业在该地区的出现。在过去，展示的是公元前10000年左右邦纳维尔湖的排水。这里是大盐湖的祖先，横跨犹他州的大部分地区，平均深度为数百英尺，通过一个塌陷的狭窄通道流入斯内克河，失去了大部分的水量。用户选择过去事件的开始，可以看到巨大的湖岸，以及包括猛犸象和巨型树懒在内的各种野生动物。仍然处于不确定模式，也有一些粗略绘制的人类；古印第安人是否在那么早的时候就出现在犹他州，这是有争议的。可见的旗帜对北方来说是一个有趣的特征。用户可以去滑坡现场观看。通过选择洪水的终点，用户可以在30秒内看到内海的流失，海岸线大大缩小。最后，用户可以缩小到今天，看到当前的文化特色和遥远的湖泊。

Graphical Navigation of the Earth in Space and TimeAn explosion is occurring in the availability of on-line data relating to archeology and related disciplines such as paleontology, geology, and paleohydrology.Much of this is geometric information, either scanned from the real world or hand-modeled. Our research aims at utilizing a variety of tools from computer graphics to allow access to this data in a natural manner. Our specific interest is in developing novel methods for displaying how cultural artifacts change over time and space. Ultimately, we envision what amounts to a spatial/temporal graphical browser for data related to the Earth.A session with the hypothetical systemA user's browser displays the view from the University of Utah over Salt Lake City with the Great Salt Lake visible on the horizon. The images have the pen-and-ink and watercolor style of architectural \presentation graphics" with detail and texture indicated with just a few strokes, and most colors muted to make the lines prominent. This is the same style used in most manuals and textbooks. The user first moves across the rendered city in the air, looking down at the bustling people and traffic. A particular building catches the user's eye. The user clicks the mouse and a web browser brings up information known about the building, such as its being built in 1870. The user adjusts the time indicator back to 1870. Over the course of thirty seconds (based on the user's preference settings and heuristics) the adjacent buildings come and go, and a trolley system appears and disappears in front of the building. The user is now in 1870 and has a much clearer view of the lake to the west. The user moves to the lake, and can see moving water and small amounts of human activity. The user now more aggressively moves backward in time to 9000 B.C. and watches the shores of the lake fluctuate widely as the water rises and falls. Now the user asks the system to "flag" areas where the database has high densities of unsynthesized data. A flag appears to the west of the lake. The user zooms to this and sees two caves. A click on the caves opens a browser window that indicates the caves are the oldest known inhabited sites in Utah, and were used over several thousand years by paleoindians. The user enters Danger Cave, and observes a group of paleoindians preparing food over a fire. The user now turns selects "uncertainty rendering". Here objects in the database that are stored with a high confidence are rendered with clean lines and detailed textures. Objects stored with low confidence are drawn with sketchy lines and no color. For example, the petroglyphs near the mouth of the cave still exist and thus have high confidence. Petroglyphs in the back of the cave, if they existed, have been destroyed by rock fall and erosion. They have been created speculatively by the archeologist based on other sites, and are thus drawn with low confidence. Note that the system merely accesses archaeologic data. More sophisticated archaeologic uses would be done by other programs, just as the current Web is not used for general data manipulation. The user now exits the cave and asks for the nearest significant events in the past and future near the cave. In the future is shown the arrival of agriculture in the area around 200 A.D. In the past is shown the draining of Lake Bonneville around 10,000 B. C. Here the ancestor of the Great Salt Lake, spanning most of the state of Utah and having an average depth of hundreds of feet, lost most of its water volume through a collapsed narrow pass into the Snake River. The user selects the beginning of the past event and can see the shores of the giant lake, and a variety of wildlife including mammoths and giant land sloths. Still in uncertainty mode, there are also a few sketchily drawn humans; it is debated whether paleoindians were present in Utah that early in time. A visual flag indicates an interesting feature to the North. The user can go witness the site of the landslide.By selecting the end of the flood, the user over thirty seconds can watch the inland sea drain, and the shorelines vastly contract. Finally, the user can zoom back to the present day to see the current cultural features and distant lake.