SURFACE

PolyBevel

 

The Surface->PolyBevel command in the Model module lets you engrave into a polygon mesh object. PolyBevel engraves a user-tagged region of a polygon mesh and bevels the outline of the region with a user-defined bevel. This is especially useful in conjunction with Polygon->MergeGeometry, which allows you to merge the geometry of a curve into a polygon mesh. You can also use it in conjunction with Tag->SplineTag to simplify the process of tagging the interior of a region created this way.

Procedure

  1. Create a polygon mesh and tag a region of points on it, and then create a curve to act as a bevel.
  2. Choose the Surface->PolyBevel command.

    The PolyBevel dialogue box is displayed.
  3. Set the parameters as desired.
  4. Follow the prompts to select the model and then the bevel.

 

Parameters

 

Dominant Projection Plane

Select this option for the plane which contains the "dominant" view of the tagged region. The region does not have to be in that plane, but the region cannot curve back on itself when viewed in this projection plane.

Discontinuity Angle

Determines how smooth the bevelling curve is. A higher value means a smoother bevel.

Influence Range for Interior Points

For the best results, PolyBevel must decide how to move the interior points of the tagged region that "get in the way" of the bevelling operation. There are two options for how to do this:

Automatic Computation

With this option selected, PolyBevel automatically performs fitting calculations on the interior points of the tagged region.

Manual Computation

With this option selected, PolyBevel incorporates the Start and End distances to affect interior points. Points closer than Start from the region outline are fully affected by the movement of the outline points, while points further than End are not affected. Between the Start and End, there is a smooth dropoff in the calculated effect. For good results, these parameters should "bracket" all interior points of the region that are in the way of the bevelling operation. This generally corresponds to the height of the bevel.

Note:
A large part of this effect relies on the bevel itself: its y magnitude corresponds to the width of the resulting bevel on the region, and its x magnitude corresponds to the resulting depth of the bevel on the region.

Tip:
In some cases, the shapes of the tagged region and the bevel cross-section are too complex for PolyBevel to produce accurate results. PolyBevel uses several heuristic algorithms for handling the interior tagged points of the region. If the results don't look right, make sure the tagged region is aligned with one of the three coordinate planes (xy, xz, and yz) as much as possible, then select that plane as the Dominant Projection Plane option.

Start and End

The beginning and ending distances that affect interior points. Points closer than Start from the region outline are fully affected by the movement of the outline points, while points further than End are not affected. Between the Start and End, there is a smooth dropoff in the calculated effect.

 

Last updated 02-apr-1998