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Modeling Terrain in SketchUp by using Contour Lines

Cartographers, architects, and surveyors use contour lines to create maps from 3D terrain. You sometimes need to model the contour lines of a site in 3D. A three-dimensional surface automatically generates from contour lines using the From Contours tool in the Sandbox.


The Contours tool has some things to keep in mind. You need to do both steps to use this tool. Once you understand how it works, you can easily use From Contours. You can use any contour lines you would like to create a surface. If the Sandbox toolbar is visible, choose ?Draw? ?Sandbox? in Contours from the menu bar.

Lift Up Contour Lines

It is necessary to lift your contour lines. When using the Contours tool, contours that already align in 3D space create a surface. In most cases, you will have to work with contours in 2D drawings, so you will likely have to lift each one using the Move tool. It takes a lot of time but is necessary. You can work quickly just by oiling up the Select tool, putting on some tunes, and getting to work.


You can convert a contour line into a group using SketchUp's Contour tool. In this case, you left with the original lines them; they can be moved, hidden, or deleted. Separate these items into a separate group, and hide that layer until you need it again.

Open Hidden Geometry to edit New Surface

However, contours have their limitations as well, as they are extremely useful but have limited use. Having too many faces and edges can be a serious slow-down since they can create enormous amounts of geometry.

A surface that is too large or takes forever to turn into contours, or a newly created surface that turns your computer blue and causes it to curl up into a fetal position, requires you to follow a few steps:

1. It operates in a smaller area. Even though it would be great if your SketchUp model included the entire neighborhood, you may have to narrow your scope. Modeling should be focused on what you need.

2. Each contour line must be used twice. The resulting size of the surface is halved by doing such a thing.

3. Put contour lines on a scale of 1-10. It's a little difficult to explain, but here are the basics: The Contours tool connects adjacent contours by creating triangles with their edges. In each contour line, the number of individual edge segments determines how many triangles it creates.

4. If you didn?t create the contour lines, there?s a good chance that you imported them from a CAD file, so the level of detail you want has no bearing on what you get.

Use whatever contour lines you like

One of the most powerful ways to create organic, non-boxy forms in SketchUp is to draw your edges and generate a surface from them using From Contours.


Some amount of cleaning is usually required after the Contours create a surface. Eraser allows you to delete extra geometry. You will have plenty of material lining the edges of your surface. Aligning triangular shapes with the Flip Edge tool is possible.


On topographical maps, you see squiggly lines that indicate hills and valleys.

A contour line or contour is a line that represents the contours of the terrain, and every point on a line on a line is the same height above sea level. There is steep ground between lines where they are close together. The slope is less steep where the lines are far apart.

To learn more, watch the following video tutorial.

Video Source: Designer Hacks

Modeling Terrain in SketchUp by using Contour Lines