In this exercise, you will learn to get topography from SketchUp Pro and bring it into Rhinoceros. You will also learn to create a NURBS surface using a Curve Network from a Polygon (triangulated) Mesh.
- Follow SketchUp 4.1 [terrain] to acquire a topographic surface of your choice (don't pick something that is too steep (like Half Dome) or too flat.
- Please pick a moderate terrain (Lake Tahoe, Oakland Hills, etc.) for this exercise.
- With a saved SketchUp Version 2018 .skp file, Follow Rhinoceros 5.23 [SketchUp Topography] and Rhinoceros 5.24 [curve networks] to create a NURBS surface using a Curve Network from the polygon mesh imported from SketchUp.
- Note: For large topography, you may change the Edge Curves setting in the Curve Network dialog box to be 0.1 instead of 0.01. This will result in faster surface creation (though a bit less accurate).
- Once your surface has been created, rebuild your surface using the rebuild command (Rhinoceros 5.19 [rebuild]) with U and V values at 100 each.
- Now, on a new layer, use the contour command (Rhinoceros 5.24 [curve networks]) and use the direction perpendicular to the contour planes as the z-axis. (You used x-axis and y-axis in step 2.) Your contour interval should be 40’ (feet). This will result in standard topographic contours.
- Hide the surface created in step 3. In the top view, draw a flat surface larger than the contours created in step 4. Use the project command (Rhinoceros 5.13 [project]) to project the contours onto the surface you just created. This will create a flat set of contours. Select these flat contours and use File>Export Selected... to create an AutoCAD file of these contours.
- Take a screen capture of your topography lines (like I do in the lecture) and post the resulting image to the course website.
- You do not need to comment on this exercise!