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Mapping topography and creating contour maps with QuickSurf |
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| Natural Topography |
A color contoured map of natural topography created using Quicksurf.
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| Bluefield, West Virginia digital elevation model in QuickSurf |
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QuickSurf loaded this 1.44 million point DEM in 60 seconds. The grid is displayed above (colored by elevation) and shows the south end of the Appalachian mountains where the folded sedimentary rocks flatten out to the northwest allowing a dendritic drainage to develop. Topography may be colored by elevation, slope, visibility, lighting, shadowing or even the value of another surface. Although this image is in plan view, it is a fully three dimensional model. There is a tech note on DEM data in the QuickSurf technical support web. |
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Zooming in on a small area of the DEM above and contouring just a few stream drainages produces a contour map at any countour interval you request. In this example, only contours lower than a given elevation were used. |
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QuickSurf starts with spot elevations and optionally break line data, whether in a text file or in a drawing file. The surface may then be displayed as contours or polyface mesh entities. Any drawing entity such as line work may be draped onto the surface to change your 2D model into a 3D model. When working with natural topography contours based on a grid work well as shown below. |
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| Click on image to enlarge |
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| Topography with break lines |
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QuickSurf can smoothly blend your design elements into existing topography, including seamless matching of rolling topography and your design, such as the road and ditches seen in an oblique view here. |
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The white lines are break lines, which indicate where the surface may have an abrupt change in slope. These breaklines were all calculated by QuickSurf starting with the original topography, a road centerline and a cross-sectional road template. The ditches and daylight lines (where the design topography merges with the existing topography) are all calculated in one pass by the apply section command. QuickSurf will maintain the smooth rolling topography outside of the design area.
The resulting model may be displayed as contours as shown here or as a triangulated grid shown below from the same oblique viewpoint. |
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| Color by Elevation |
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QuickSurf can smoothly blend your design elements into existing topography, including seamless matching of rolling topography and your design, such as the road and ditches seen in an oblique view here. |
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The white lines are break lines, which indicate where the surface may have an abrupt change in slope. These breaklines were all calculated by QuickSurf starting with the original topography, a road centerline and a cross-sectional road template. The ditches and daylight lines (where the design topography merges with the existing topography) are all calculated in one pass by the apply section command. QuickSurf will maintain the smooth rolling topography outside of the design area.
The resulting model may be displayed as contours as shown here or as a triangulated grid shown below from the same oblique viewpoint. |
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| Color by Slope |
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The picture at the right is the same geometry as above, but it is colored based upon local surface slope. The road surface, ditches and road cuts and fills are all constructed at a constant slope in this particular model, so they display in the same color indicating constant slope. |
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