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Manual - Blender 2.43

[edit] Proportional Edit

When working with dense geometry, it can become difficult to make subtle adjustments to the vertices without causing nasty lumps and creases in the model’s surface. When you face situations like this, use the proportional editing tool. It acts like a magnet to smoothly deform the surface of the model, without creating lumps and creases, by also modifying unselected vertices within a given range, not just the selected ones.

[edit] Options

Proportional Editing icon.

Falloff menu.

The Proportional Editing mode menu is available in Edit mode, on the 3D View header.

Off (O)

Proportional Editing is Off, only selected vertices will be affected.

On (O or AltO)

Vertices other than the selected vertex are affected, within a defined radius.

Connected (AltO)

Rather than using a radius only, the proportional falloff propagates through connected geometry. This means that you can easily proportionally edit the vertices in a finger of a hand, without affecting the other fingers, since although the other vertices are nearby spatially, they are far away following the topological edge connections of the mesh. The icon will be cleared (grey) in the center when Connected is active.

Falloff

While you are editing, you can change the curve profile used by either using the Mesh → Proportional Falloff submenu, using the toolbar icon (Falloff menu), or by pressing ⇧ ShiftO to toggle between the various options.

Constant, No Falloff.	Random Falloff.
Linear Falloff.	Sharp Falloff.
Root Falloff.	Sphere Falloff.
Smooth Falloff.

Influence circle.

Influence

You can increase or decrease the radius of the proportional editing influence with the mouse wheel WheelUp /WheelDown or PageUp/PageDown respectively. As you change the radius, the points surrounding your selection will adjust their positions accordingly.

[edit] Examples

Switch to a front view (1 NumPad) and activate the grab tool with G. As you drag the point upwards, notice how nearby vertices are dragged along with it. When you are satisfied with the placement, clic LMB to fix the position. If you are not satisfied, cancel the operation and revert your mesh to the way it looked before with RMB (or Esc key).

You can use the proportional editing tool to produce great effects with the scaling (S) and rotation (R) tools, as (A landscape obtained via Proportional Editing) shows.

A landscape obtained via Proportional Editing.

Combine these techniques with vertex painting to create fantastic landscapes. (Final rendered landscape) shows the results of proportional editing after the application of textures and lighting.

Final rendered landscape.

Manual