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The GD&T callouts area lets you control the display of GD&T callouts within an imported CAD model. It helps reduce screen clutter by making such callouts temporarily hidden as they reach or approach a view angle parallel to your current view angle. This option is disabled if your part model doesn't have any embedded GD&T callouts.
Do not confuse these GD&T callouts with the Feature Control Frame dimensions that are created inside PC-DMIS. The GD&T callouts are essentially CAD objects themselves. There were not created inside PC-DMIS. Rather, they were created by the CAD software used to create the model and are stored with the model.
Hide normal view angle - This option tells PC-DMIS to hide the callouts when they cross a threshold of degrees parallel to your view angle. The box to the right of the check box lets you specify the threshold of degrees parallel to your view angle. The default value is 30.
Suppose you have a GD&T callout that points to a cylinder feature on the top of your part. Now, suppose you type a value of 45 degrees in the box. When you 3D rotate the part, the callout remains visible until the rotation of the part meets or exceeds 45 degrees.
If you want to always show the callouts, clear the check box.
Movie Demo
The small movie below demonstrates the callouts being hidden once they reach the threshold. In this example the threshold is initially set for 15 degrees and then later set to 45 degrees.
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