Selecting Patches for Part Surfaces
The Patch Selection Control tools include grow and shrink tools which facilitate the selection of patches for splitting.
These Patch Selection Control tools are only available for parts. There are no tools included for region boundary based patch splitting.
There are five Patch Selection Control tool buttons which are accessible once you select the Split by Patch option. These buttons become active once a Part Surface Patch has been selected from the Part Surface Patches group box or from the Geometry in the Graphics window. Use the <up> and <down> arrow keys on the keyboard to cycle through the patches. If all patches for the part surface are selected, then only the Patch Clear and Patch Shrink buttons are available.
The button descriptions are as follows:
| Tool | Hotkey | Description |
|---|---|---|
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SHIFT + G |
Grows the selection one patch in each direction based on the perimeter vertices surrounding the initial patch selection. |
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Shrinks the selection one patch in each direction based on the perimeter vertices of the selected patches. If all patches are selected then a shrink may not be possible. At least one free patch perimeter edge is required to start shrinking from. The result of growing a patch and then shrinking it does not always result in the original patch selection. |
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SHIFT + M |
Opens a dialog which gives you access to a variety of patch multiple grow options. |
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SHIFT + I |
Selects the inverse of the Part Surface Patches that are selected. |
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SHIFT + N |
Clears any selection of Part Surface Patches. |
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(
(
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(Patch multiple grow options dialog
- Number of Steps
- Specifies the number of steps the patch selection is grown for. There
are two options for this:
- Infinite—grows the patch selection infinitely. Performing an infinite grow without including some reasonable Break Options can potentially take a long time.
- Finite—allows you to specify a finite number of patch growth steps.
- Grow Options
- Allows you the option to grow your selection based on growth from edges
or vertex. There are two options for this:
- Edge Based Growth—grows the selected patches from the outer edges of each selected patch.
- Vertex Based Growth—Grows the selected patches from the outer vertex of each selected patch.
- Patch Perimeter Break Options
- Allows you to specify the type of feature which the patch perimeter
grows to before breaking the selection. You can set the Patch
Perimeter Break options to any or all of the following
options:
- Break at Feature Edges—breaks the patch selection when the patch perimeter reaches a part curve.
- Break at Non-manifold Edges—breaks the patch selection when the patch perimeter reaches a non-manifold edge
- Break at Sharp Angles—breaks the patch selection when the patch perimeter reaches edges between faces that meet at this angle or sharper.
- Angle—becomes active when the Break at Sharp Angles option is activated and allows you to specify the sharp angle. The units of the sharp angle are specified in degrees only.
The break options provided are similar to those in surface repair. However, the break options criteria is only assessed on patch perimeters and not on patch interiors. For example, if a patch contains an interior sharp angle (as opposed to a sharp angle at the patch perimeter) then this sharp angle is ignored and the patch will always be completely grown into. Similarly, part curves and non-manifold edges that are contained within a patch are also ignored. It is not possible to grow into only part of a patch - only whole patches are grown into, regardless of any break option features within that patch.
Smart Selection of Patches
Smart selection of patches lets you quickly grow a patch until it reaches a natural break point in the geometry. You can use smart selection to grow a patch until it reaches a natural break by double-clicking on a patch.
To combine a smart selection with any patches you have already selected, press and hold <Ctrl> before you perform the smart selection.