Feature Points

Dimensional and positional measurements detect feature points found within the defined region (whether it's a measurement region, feature region, reference region, and so on) and then compare measurement values taken at the selected point with minimum and maximum thresholds to produce a pass / fail decision. Feature points are selected in one or more Feature parameters in a tool's Parameters section, and are used for all of the tool's measurements.

It is important to note that the feature points described here are distinct from the geometric features generated by some tools, and which can be taken as inputs by other tools. Feature points are simply the location in the scan data at which a measurement tool performs a measurement. So, for example, if you set a Profile Position tool's Feature parameter to Max Z, it will return the X and Z positions of the point that is at the highest Z value. Geometric features are a data type produced as output or taken as input by a tool. (For more information on geometric features, see Geometric Features.)

The following types of points can be identified in a measurement region. The availability of a feature point type is tool-dependent.

The following are represented as profiles for clarity. Many Surface tools use feature points.

Point Type	Examples
Max Z Finds the point with the maximum Z value in the region of interest.
Min Z Finds the point with the minimum Z value in the region of interest.
Min X Finds the point with the minimum X value in the region of interest.
Max X Finds the point with the maximum X value in the region of interest.
Average Determines the average location of points in the region of interest.
Corner Finds a dominant corner in the region of interest, where corner is defined as a change in profile slope.
Top Corner Finds the top-most corner in the region of interest, where corner is defined as a change in profile shape.
Bottom Corner Finds the bottom-most corner in the region of interest, where corner is defined as a change in profile shape.
Left Corner Finds the left-most corner in the region of interest, where corner is defined as a change in profile shape.
Right Corner Finds the right-most corner in the region of interest, where corner is defined as a change in profile shape.
Rising Edge Finds a rising edge in the region of interest (moving from left to right).
Falling Edge Finds a falling edge in the region of interest (moving from left to right).
Any Edge Finds a rising or falling edge in the region of interest.
Median Determines the median location of points in the region of interest.