TOPOMAPPER Compare Maps Nutzungsbedingungen Scale = 1 : 111m z:3 2000 km 1000 mi Base Layer Web mapping client comparison v.6 This comparison aims to serve as a basis for those seeking a first approach to Web mapping technologies at the client side. In the sixth version a number of projects have been added and the whole set of clients has been categorized in order to distinguish them better, since there are currently forty four (44) Web mapping clients in the comparison. Web mapping clients play a significant role in Geoportals of Spatial Data Infrastructures (SDI) allowing the visualization of spatial data from several sources. cartography - How do I compare two maps to determine which is better This reply describes an objective method to measure arbitrary discrepancies between two spatial datasets. Such discrepancies can include shifts of position, changes of shape, and features present in one dataset but not in another. This reply does not provide any means to determine which is "better," because that depends on much more than just the data and it particularly depends on what the data will be used for. Background A good foundation for a large set of such measurements relies on the Euclidean distance transform of each dataset.
Projections on Bing, Google I have lately seen several blogposts confused about which datum and projection Microsoft’s Live Maps (Virtual Earth) and Google Maps use. As most people already know by now, they render the round earth onto a flat screen using a Mercator projection. I think the confusion comes from that they actually use two spatial reference systems at the same time: Geographic Longitude/Latitude coordinatesystem based on the standard WGS84 datum.
Comparing US states with countries: Stateside substitutes Which countries match the GDP and population of America's states? IT HAS long been true that California on its own would rank as one of the biggest economies of the world. These days, it would rank eighth, falling between Italy and Brazil on a nominal exchange-rate basis. But how do other American states compare with other countries? Taking the nearest equivalent country from 2009 data reveals some surprises. Who would have thought that, despite years of auto-industry hardship, the economy of Michigan is still the same size as Taiwan's? HTML5 Canvas: An Open Standard for High Performing GIS Map Visualization in Web Browsers Summary: The evolution of GIS on the Web has, until recently, been limited by traditional Web mapping technologies. The increase in GIS requirements in the Web and mobile world has necessitated the development of a new breed of map engine. This article, by Dino Ravnić, the co-founder and CEO of GIS Cloud, Ltd., provides an overview of existing mapping technologies and the reasons why he decided to build a unique vector mapping engine in an effort to give the Web a full featured GIS.