1. Select a node in a path of 2 or more nodes
2. Press 'Mirror Node Movement' button
3. Select another node in the same path
4. Now when one node is moved the other node also moves, but in the opposite direction.
5. End mirror behavior by selecting either node and clicking the button again.
This is useful for quickly editing shapes that need to be symmetrical (well duh, I guess).
**Perhaps you could select groups of nodes as well. (With a check that makes sure you're not putting a node in both groups.
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Relative Positioning
1. Select a node (or group of nodes) or object
2. Press Relative Position button
3. Select another node, path, object, guide, etc
4. The user is prompted to put in a value (positive or negative) for how far X and Y the first node should be from whatever was selected second.
**Do I have to point out how awesome this would be?
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