Redevelopment of Place Van Zeeland, Belgium - Google SketchUp Workshop: Modeling, Visualizing, and Illustrating - page 71

Often, this extrusion generates polygons with flipped faces - the blue back faces
will point outward. For final rendering in Kerkythea, it is essential that all faces in
the model have their front face showing; otherwise, Kerkythea it will not “see”
the surface. The Front Face plug-in was used to flip the faces back again: By simply
running the cursor over the flipped faces, they are flipped back automatically.
Then you can just click on the Select tool to terminate the Front Face operation.
The Tools on Surface plug-in was then used to carry out an Offset on Surface
operation for the part of the sidewalk surface that corresponds to the width
of the curb. Since the offset operation is carried out all around the perimeter
of the surface, the Line on Surface and Erase Contours on Surface functions of
the plug-in should be used to correct any discrepancies in the offset.
FiG 4.12 Offsetting the curb.
The next stage was to create the underside of the sidewalk, corresponding to
the width of the curb and the vertical extrusion corresponding to its height.
These elements were selected and grouped, separating the sidewalk surfaces
from those of the road.
FiG 4.13 Isolating the faces of the
curb in their own group.