One of the strengths of OCAD is the generation of smoothed contour lines.
With the latest Service Update, a combined method of TPI and 3D smoothing is used for the calculation, which leads to improved results. The file size also shrinks, because at the same time irrelevant contour vertices are removed and the contours are converted into Bézier curves.
In our example, the not smoothed contours appear brown. The smoothed contours according to the new method (blue) are cleaner and show the terrain more precisely than according to the old smoothing method (green).
How contour lines can be generated is described in detail in our Wiki.
A hillshade is a shaded relief picture of the surface. Important for a hillshade is the position of the imaginary light source, which is taken into account for shading the image.
Normally, the direction of the light source is 315° (north-west). Since the Service Update 20.5.3, it’s also possible to choose the option Multi-directional. It is a composite image made up of four images in which the light source comes from different directions. Like this, the terrain is more realistically represented, and overexposed and nonilluminated areas of the map are more balanced.
In OCAD, Hill Shading can be created from the DEM menu or from the DEM Import Wizard.