The Squeeze modifier compresses or expands an object as a function of position along the local symmetry axis of the modifier. In the main parameters panel you can choose from three basic functional modes: Percent, Inverse and Add When you click on the Edit button, a graph window opens, which allows you to set the precise way your object will be squeezed (see figures below). As usual in these graphs, you have the option to use an Interactive (or manual) or Analytic function for the graph. In the Percent mode, the value of the graph indicates the fractional amount by which the mesh is compressed, i.e. scaled, to the squeeze axis. r(x) = 1 - r0(x) * f(x) where r and r0 are the final and the original distances from the symmetry axis, respectively, f(x) is the graph value and x is the position along the axis.

In the example below, the squeeze has been applied to a cylinder using the Interactive mode, where you can use any number of manually inserted control points to determine the shape of the graph. In that case the graph actually shows the final shape of the object. Other initial shapes will of course not follow the graph after applying the squeeze modifier.

In the Inverse mode, the scaling is as the graph shows, i.e.

r(x) = r0(x) * f(x)

In the example below, we have used an analytic function to set the shape of the graph. Se the f(x) function at the bottom of the graph panel.

In the Absolute mode the graph amount is added to the current distance from the symmetry axis.

r(x) = r0(x) + f(x)

Using positive values will expand the object, while negative value will squeeze it. Negative values are limited to squeezing to r(x) = 0.

The following gif animation shows a practical example of how to apply a squeeze modifier to an initial spherical primitive.