Mesh Analysis

In this tutorial, we will show you how to analyse both whole meshes and regions of meshes in your model. We will be using the Mesh Analysis portion of CellBlender and a separate addon called MeasureIt. The Mesh Analysis tool will be more useful when trying to ascertain properties of the entire mesh, whereas MeasureIt will be more useful when dealing with a portion of a mesh.

Note

Some of these same issues are discussed in the Repairing Meshes and Using GAMer to Refine a Mesh tutorials.

Area, Volume, and Topology of Whole Meshes

To find the area, volume, and topology of an entire mesh, we will use CellBlender's Mesh Analysis tool. Expand the Mesh Analysis panel near the top left of the screen.

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Make sure that the object you're analyzing is triangulated first. Next, select the object in Object Mode (right click on it) and hit Analyze Mesh.

The tool will only be able to report a volume if the object is a watertight manifold mesh (i.e. there are no holes in your mesh and all surface normals are consistent). Additionally, you usually want your surface normals to be facing outward. If they are facing inward, the volume reported will be negative.

Area and Length of Mesh Regions

We will be using Blender's MeasureIt addon to measure regions of a mesh. This addon is included with Blender but is not enabled by default. To enable it, go to File>User Preferences. Under the Add-ons tab, search for MeasureIt. Select the check box to enable it.

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Near the main CellBlender tab, you should now see another tab called Measureit. Click this now. Before you do anything else, make sure you hit the Show button. Otherwise, all of your measurements will be hidden. Next, in Edit Mode, select two vertices and hit Segment to find the distance between them. You can also find the area of one or more faces by selecting them and hitting Area. Unlike the Mesh Analysis tool, these measurements will be updated live if you happen to move or resize the elements (vertices and faces).

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