Tessellation
The analysis is based on triangulated data. That means that surfaces are converted into a facet model before they are checked.
- Facet length
- Defines the maximum length of the facets, regardless of the surface curvature.
Flat regions are identified precisely with this method, however, it requires more computing time. The smaller the value for the facet length, the more precise, but also slower is the computation.
- Tolerance
- Defines the maximum deviation of the facet model from the surface for a curvature dependent tessellation.
The surfaces are subdivided into smaller facets until the distance of the planer facets from the surfaces is smaller than this value. Through this, large facets are created on areas with a lower curvature, and smaller ones on surfaces with a stronger curvature. this method delivers a quick result, but in flat regions it may lead to results that are hard to interpret.
Options
- Type: Chord, Local
- Defines the analysis method.
Two methods are available: the ruler/disk method (Chord) and the local method (Local). For a detailed description of both methods, see What are the Verification Methods used in the Flat Region Analysis?.
- For performance reasons it is recommendable to start the computation with Local (default setting). This method delivers a considerably quicker result than Chord.
- If all surfaces are marked in green, there are definitely no flat regions. If red areas are found, you should definitely use Chord afterwards in order to exclude saddle points and other uncritical areas. This method delivers a very precise result, but is considerably slower than Local. The subsequent deviation analysis (Selection of points via selection field Points) also runs faster with the setting Local (see also Proceeding of the Deviation Analysis.
- Display: Both, Discs only
- Defines the display mode for the analysis result: You may choose between display of surfaces and discs or discs only.
- Length, Distance
- Defines the length of the virtual ruler (chord) and minimum distance between ruler and geometry for Chord. These parameters define the minimum curvature.
See Flat Region Check in Practice and Ruler/Disk Method (Chord).
- Radius
- Defines the minimum curvature radius for Local.
See Definition of Flatness and Local Method (Local).
- Rotation Angle
- Defines which type of flatness shall be found. The system checks within the sector defined by the rotation angle whether the minimum curvature is kept.
For a detailed description of the rotation angle definition including illustrative figures, see Which Importance Has the Rotation Angle?
The angle of rotation can also be specified directly in the text box. The following table shows how the rotation angle should be set in order to find the different types of flatness:
| Flatness Type
| Slider Position
| Rotation Angle
| Related Figure |
|---|
| Flat regions in one direction | At the very left | 1deg | Flatness in one direction (Rotation Angle = 1deg) |
| Flat regions in a sector of directions | Between left and right end | Between 1deg and 180deg | Flatness in a sector of directions (Rotation Angle between 1deg and 180deg) |
| Perfectly flat regions | At the very right | 180deg | Flatness in all directions (Rotation Angle = 180deg) |
More Info
Displays deviations.
- Display
- Displays values in the work area.
- Apply Modes
- Defines the update mode of the active feature while editing it.
- Dynamic
- Feature update occurs dynamically when moving handles or editing parameter
values by sliders in the dialog box.
- This option is not available for each command.
- Static
- Feature update occurs only after releasing the handle.
- Preview
- Displays a preview when geometry is modified by means of the handle and LMB pressed. The
original geometry remains unchanged. Feature update occurs only
after releasing the LMB.
- This option is not available for each command.
- None
- Feature update occurs only after selecting Apply.
- Deviation: Max. Distance
- Displays the maximum deviation of the calculated result.