Release Notes Limitations > Meshes

Modeling limitations

Limitations related to curve and surface creation and evaluation.

General

Duplicating a canvas doesn't duplicate all canvas information.

When you select a canvas and duplicate it, a new infinite plane is created which does not contain all of the canvas plane information (layer stack, name, etc.)

Workaround: Use copy and paste (rather than duplicate) to get the complete canvas information.

Section lines and curvature combs remain after exiting Dynamic Section tool.

If you enable Persistent sections in the Dynamic Section tool (Evaluate > Dynamic Section), the sections remain visible even after you exit the tool.

Workaround: Select all the surfaces that have the persistent sections, go into the Dynamic sections tool again, and then pick nothing.

Chordal fillet fails to keep rail distance with edge align. The chordal distance cannot be maintained when edge-align is turned on.

To resolve this problem turn off the edge-align option.

A symmetry or symmetric object is an object that exists only when symmetry is turned on for its layer.

Construction history that involves symmetry objects means a curve/surface built or modified using a tool that creates construction history and a symmetry object is being used as a constructor (for example, as a gen or path curve in the Rail tool).

Any delete operation (and this includes Edit > Cut plus everything in Delete) will also delete all construction history that involves symmetry objects. Undo will bring back the deleted object, but will not restore the construction history.

If you Edit > Ungroup (with Preserve Position off) constructor and target objects that have been grouped together (for example, a cube and a round on the cube, an object and an instance of the object), construction history will update.

Using the Align tool with Explicit Control on will not produce good results on surfaces that have a large gap between them.

Locators created on a symmetric half are deleted when you save or retrieve a file or use tools that modify the group nodes.

For example, a surface continuity locator created between a surface and its symmetric half is deleted if you save a file.

If an object has been scaled, the curvature on its cross section, created by the Evaluate > Cross section tool, is scaled twice.

Zero transform the geometry before evaluating the curvature on its cross sections.

Curves

The successful use of Curve Edit > Create > Combine curves sometimes depends on the order of picking the input curves.

Some input curves to Combine curves may result in unsatisfactory results, accompanied by the following warning message:

Curves are too complex. Approximation may be inaccurate.

Picking the curves in a different order often corrects the problem. Try picking the second curve first.

Using Curve Edit > Create > Duplicate curve with the Rebuild Type set to UNIFORM KNOTS on a curve-on-surface creates an inexact copy. The results may not be within the specified tolerance of the original curve.

To avoid this problem, use the CHORD parameterization Rebuild Type when duplicating curves on surface.

Manipulators in Blend curves and Project Tangent will line up to either the U or V value, depending on which direction of a surface you point to initially.

Unless the U and V directions are at 90 degrees in world space, then you cannot use the manipulator to get the other alignment.

Make sure that the curves are correctly aligned. Dolly in if necessary to see more clearly.

Snapping the alignment of a curve tangent to the manipulator axes does not keep the alignment fixed in the same way as setting the alignment in the Project Tangent Editor window.

To fix a specific U, V, or Normal alignment, you must select that alignment from the editor window menu.

Blend curves with chord length parameterization don't work properly on models of large scale

Workaround: Use the uniform option when the scale of the models to which the blend curve is being attached is very large.

Surfaces

If the Ball Corner is the currently selected tool when a file is retrieved, and the file has different tolerance settings, the ball corner tool will still use the old tolerance setttings for the next surface it constructs.

Solution: Reselect the ball corner tool by clicking on its icon. Reselecting the tool will help guarantee it's picking up the current tolerance settings. This is not only applicable for Ball Corner, but for other tools as well when tolerances have changed - not just via file retrieval, but also when editing the Construction Options. Restarting a tool after the tolerances have been changed will help ensure the tool is picking up the new tolerances.

Adding edges to a built network with the Round tool is still not implemented. Users must revert the build and add or delete edges at that time. The existing profiles are retained so it can be rebuilt with relative ease.

If you have an extrude history command built from a face (created prior to StudioTools 13) the caps will be lost if you update the history.

The new interior flow control parameter is left empty when AliasStudio version 12 files are loaded into AliasStudio version 13 or later. Any free-form blend and surface fillet (Palette > Surfaces > Multi-Surface blend > Freeform or Profile blend) will have nothing specified for this parameter.

Surfaces > Fillet surfaces > Surface fillet may not be able to create a fillet with a surface that has two intersecting points.

If there are two surfaces intersecting one another at more than one point, detach one of the surfaces so they only have one common intersection.

If a blend curve is attached to a surface that is the result of a curve network, updating that curve network may delete the history on the blend curve.

ObjectDisplay > Diagnostic shading > Surface evaluation > Draft angle may not display the correct angle.

Choose Transform > Zero transforms for the surface you are evaluating to update the draft angle display.

You may not be able to create a variable radius fillet between surfaces that have a variable gap between them.

If the surfaces are trimmed, untrim them, create the fillet, then trim them.

Pivot points and local axes of surfaces created within Construction Plane mode do not reflect the proper environment - they are created relative to the Worldspace coordinate system.

Change the position of the pivot points manually and reset the local axes to reflect the proper working environment.

When you turn on Explicit Control for the Draft tool, Degree and Spans are not automatically set to the values used when Explicit Control is off, which may produce poor results.

Manually set the Degree and Spans values to produce the desired result.

If you untrim a trim-divided surface back to before the trim-divide operation, only one of the divided pieces will have its prior construction history. All other pieces won't have any construction history.

If you try to duplicate a curve-on-surface with an extremely large number of spans (for example, greater than a thousand spans) using the Curve Edit > Create > Duplicate curve tool, AliasStudio may run out of memory trying to achieve a good fit.

When dealing with huge numbers of spans on curves-on-surfaces being duplicated, separate the curve-on-surface into manageable chunks before performing the duplicate operation.

Surfaces > Swept surfaces > Extrude   (TUBE option) has problems with multiple CVs on the path curve.

When you are using TUBE mode in Extrude, avoid path curves with multiple CVs on them, as the resulting extruded surface may have undesired twists near the multiple CVs in the path.

Meshes

You may not be able to cut a mesh (using Mesh > Mesh Partitioning > Mesh cut ) if it was produced from a tessellation (particularly if Fast tessellation was used).

Try using the Accurate tessellation method instead if you plan to cut the mesh.