Geometric and Cosmetic Select Modes

Geometric extents are based on the distances between object vertices (the three corners points of a triangle or the two endpoints of a line). Cosmetic extents are based on distances between the outermost points on the object that will be drawn with the minimum (zero) pen width. Therefore, the difference between the two modes is relevant for objects such as double lines, multi lines, and objects that have a nonzero pen width. The select mode will come into play when using snaps and assigning dimensions.

For most applications, and for greater accuracy, use Geometric select mode. There are two main advantages to using Geometric select mode:

When you scale using geometric extents, it is easy to see exactly what is going to be scaled. For example, if you scale a double-line object, the double-line separation distance and pen width are not scaled.

Geometric select mode makes this visually obvious.

When you scale an orthogonal linear object using geometric extents, you get accurate results. For example, if you scale a 1-inch horizontal line segment 200 percent along the X axis, the line segment will always be 2 inches long. If you were to use cosmetic extents, the results would vary depending on the pen width.

Tip: If you want to change the width (separation distance) or pen width of a double line, you can enter new values in the Properties window.

The disadvantage of geometric selection is that if you snap the endpoint of a wide line to another object, the cosmetic end of the line will overlap the object. You can work around this problem by selecting a line using cosmetic extents and using a snap mode to position the cosmetic end of the line.

Warning: Geometric select mode is not the installation default. If you choose to use Cosmetic select mode, zoom in closely and be careful where you snap. If you set Geometric select mode, it will remain active the next time you open TurboCAD.