Vtyjkyuk

3D Studio has a modifier called "Volume Select" that allows using an element's geometry as a sort of selection force field that influences elements in its path. It can be used to transform many at once, as illustrated below.

Is there a way to do this in Blender? If not a modifier, maybe a script? I'm trying to animate a block of cubes that shrink and grow in a pattern and something like volume selecting would help a lot.

Thanks!

Animation Nodes can be used here. The Find Nearest Surface Point node is used to compute the distance between every element and its closest surface point, the distance is then used as the scale of the elements as following:

Evaluating the distance at an interpolation gives you fine control over its rate of change:

In blender you can use Drivers.

1) In N-panel click RMB on scale and in context menu select Drivers -> Manually create later. Scale will be pink-colored

2) Open Graph Editor in Drivers Mode

3) Chose X Scale, remove all dots from curve and draw a new one (CTRL+LMB to add a dot) You can perfectly align it using Active keyframe tab.

Here will be your curve, last 2 dots must have 0 Value, to make object completely invisible in long distance.

Horizontal will be distance between objects, vertical - Scale.

4) Goto Drivers Tab

5) Setup settings:

Type - Averaged Value

Var type - Distance

Object 1 & 2 - is your current object and object-controller.

6) In N-panel RMB-click on X scale and in context menu select Copy Driver. When Paste Driver in Y and Z Scale.

7) Finally copy your objects in a grid or any pattern:

See also: For more advanced cases you can use node-based visual programing: animation nodes

1. If you want it as you showed it, create the mask first

2. Put the object to be animated in the hole less than 0,01 below the mask and make sure the mask's color is the same as world's

3. Animate the objects within the mask's boundaries

This is the fastest, simplest way and gives the desired effect. Nodes are needless complication.