




The 
calculate-layout
 generic function is used to provide a method for laying out the children of a new layout.
The generic function 
calculate-layout
 is called by the CAPI to layout the children of a layout. When defining a new class of layout using define-layout, a 
calculate-layout
 method must be provided that sets the 
x
, 
y
, 
width
 and 
height
 of each of the layout's children. This method must try to obey the constraints specified by its children (its minimum and maximum size) and should only break them when it becomes impossible to fit the constraints of all of the children. 
To set the 
x
, 
y
, 
width
 and 
height
 of the layout, use the macro with-geometry which works in a similar way as 
with-slots
.