What Is a Snapshot in Creo?

Snapshots are a capability in Creo that you use to (1) display surfaces from your model’s past history at the model’s current state and (2) create copies of those surfaces to use for subsequent geometry. This helps you understand your model’s design intent easier as well as leverage surfaces from earlier in your model’s history.

[Editor Note: This article deals specifically with quilt/body snapshots. See online help for other uses of the term.)

Surface modeling is one of the most powerful design paradigms available to product developers. By designing products with surfaces, you can create geometry that is more complex, organic, aesthetic, and aerodynamic than with basic tools like extrudes and revolves.

Often in complex models, we have surfaces that may have been:

• Imported from CAD neutral formats, like STEP or IGES;
• Shared from other models via Copy Geometry or Shrinkwrap features; or,
• Created using native Creo tools like Boundary Blends, Style, and Freestyle.

When developing our solid geometry, we often consume these complex surfaces. We merge surfaces together by intersecting or joining them to create a new surface. We trim them using curves, planes, and other surfaces. We can warp the surfaces by stretching, bending, and twisting them. We solidify and thicken them.

In the past, if you wanted to see what that geometry looked like in your model’s history, you either had to edit the feature’s definition or roll back the model via Insert Mode. Unfortunately, this made all the subsequent features and geometry unavailable to view. Similarly, if you want a copy of that geometry to use in other features, you had to perform a two-step multiple-click Copy and Paste operation.

How to Use Snapshots

Creo solves these problems and improves user workflow by introducing two new commands.

Show Snapshot displays the selected quilt as it appeared at the previous point in the model’s history while displaying the rest of the model in its current state. Multiple snapshots can be displayed at the same time to help the user understand the design intent and modeling process. The snapshots remain displayed until the user redraws the screen or clicks the background of the graphics area.

Copy Snapshot will create a copy of the selected quilt in a single click. The snapshot will appear in the Model Tree after the features that created it or before the feature that consumed it. The copy can be reordered in the Model Tree as necessary and used for the creation of additional features and geometry.

Simply right click on the feature in the Model Tree or the quilt in the Design Tree and you will see the commands.

Video: Martin Neumueller of PTC demonstrates the Preview Snapshot command in Creo.

What If I Don’t See the Commands?

This functionality was introduced in Creo 8. There’s a good chance you want to use these commands on models that were created in previous versions. These commands require a full model regeneration to be available for use. If you right click on a feature or quilt and do not see Show Snapshot or Copy Snapshot, the easy way to make them available is to drag the green Insert Here bar to your default datum planes and back down again.

If your model has a long history and you don’t want to drag the green bar for days and days, simply right click one of your default datum planes and choose Insert Here. Right click on it again and choose Exit Insert Mode. This triggers the full regeneration and the commands become available.

Customer Reaction

PTC product manager Martin Neumueller told me that the response from customers and members of the PTC technical committees to this new functionality has been overwhelmingly positive.

[Editor’s note: See what Develop3D said about Snapshots.]

Users love the convenience, simplicity, and insight that Snapshots provide. As a surface modeler myself, these commands save me a lot of time and effort on my complex projects. Give Snapshots a try in Creo 8 and find out what all the excitement is about!