Information about the surface of the Earth and the objects that are located on it, you can get using topographic maps and diagrams of different scales. They are created on the basis of high-precision geodetic measurements and contain objective and up-to-date information about the contours, areas and relief of areas of the earth's surface.
With the development of space geodesy, when using space satellite images it became possible to measure points on the earth's surface and determine all three coordinates of each of them, there are practically no "blank spots" left on the earth's surface. Even for those places on the globe where no man's foot has ever set foot, it was possible to draw up detailed maps.
According to the data of geodetic measurements, it became possible to create a three-dimensional terrain model, when it is depicted not in the form of a flat picture, but as a real copy of the Earth's surface, only in a reduced form. Such a model allows you to get the most reliable idea of the nature of the terrain and create special relief maps, on which, using a technique known as "washing", it is possible to convey all the characteristic features of the surface.
Hillshade implies the use of a color scale when a certain color corresponds to a certain height of the relief. For bump maps, so that their appearance is as close to the natural picture as possible, surfaces with low heights are painted in different tones of green, and mountainous surfaces in tones of brown. On large-scale topographic schemes, the relief is displayed using contour lines.
Bump maps are used not only as an overview, they are also of great practical importance. Without such maps, not only the construction and design of large, extended objects, such as highways, but even the construction of a small building is impossible.
Only having information about the relief of the land plot, architects and designers can "plant" the object under construction on the ground, determine the possibilities of correcting the relief and calculate the amount of work for excavation or filling of soil. On the bump map, you can determine how flood and rainwater will flow over the surface, and design a drainage system.
Large-scale relief maps, with a scale of 1: 500 or 1: 1000, are the basis for deciding where it is best to place a building on a land plot, what plants and in what places to plant on its territory. It is a working material required for a landscape designer.
