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Sometimes I see Alt+S online but I don't notice a difference between it or just using S. What does Alt+S do?

I don't get Blender wiki's brief explanation.

luigi
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  • Someone changed my title. I put alt +s not -s – luigi Mar 05 '15 at 17:56
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    In Edit Mode ALT S is used to *Scale Along Normals* in other words it moves each vertex in the direction of its local normal, shrinking or fattening the mesh. –  Mar 05 '15 at 18:29

2 Answers2

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The key command S is used to scale whatever is selected in the viewport, regardless of mode. However using the command Alt+S to scale selection along the normals is only possible in Edit Mode.

When you scale the object, all the distance ratios between various vertices and all angles will remain exactly the same, just get larger or smaller:

Scale Edit Mode

However when using the Alt+S command, blender will try to shrink or fatten the mesh. This can lead to unusual results if done on certain meshes:

Shrink Fatten Edit Mode

I have noticed that it works much better with more vertices. This really shows exactly what is happening. The inner vertices appear to have a greater weight, being moved a much greater distance. This leads to a convex shape after fattening, or a concave shape after shrinking.

enter image description here

Mr Zak
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J Sargent
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In Object mode S scales and Alt-S clears the scaling i.e. the scaling is reset to 1. You can verify this in the Properties Panel N

enter image description here

stacker
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