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As mentioned initially, you have the possibility to select particular polygons from the object and there are two ways to do this: The first method is to click on the desired face. Multiple selections are supported by pressing the Shift key. You can deselect faces by clicking on them with the pressed Ctrl (Windows/Linux) or Cmd (OS X) keyCmd key. Please note that “Select Faces” does not recognize hidden polygons by default. Everything what is under the mouse pointer will be selected, but you can activate a function to limit a selection to polygons visible to the user:
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Another way is to hold the left mouse button and drag the mouse over the desired area. This will create a rectangular selection, including faces hidden to the viewer. Once you are satisfied with your selection, deactivate “Select Faces” to confirm your choice. When the object's polygons are very small you have to increase the emitter's "Resolution" value to trigger the emission of particles.
Select Vertex
This button works exactly like the “Select Faces” feature, but is limited to the source object's points.
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