Module penrose::core::layout

User definable window arangements for a Workspace.

Layouts are maintained per monitor and allow for indepent management of the two paramaters (max_main, ratio) that are used to modify layout logic. Layout functions are only called when there is a need to re-layout a given screen and will always be given a full list of Clients that the WindowManager considers tiled. There are no restrictions as to whether or not windows may overlap or that they provide a total covering of the available screen space. Gaps and borders will be added to the Regions that are specified by layout functions by eating into the regions specified, so there is no need to account for this when writing a layout function.

Writing a simple layout function

Lets start with a very basic layout that ignores the two paramaters (max_main and ratio) and instead, simply arranges the Clients it is given as evenly spaced rows:

use penrose::core::{
    client::Client,
    data_types::{Change, Region, ResizeAction, WinId},
};

pub fn rows(
    clients: &[&Client],
    _focused: Option<WinId>,
    monitor_region: &Region,
    _max_main: u32,
    _ratio: f32,
) -> Vec<ResizeAction> {
    monitor_region
        .as_rows(clients.len() as u32)
        .iter()
        .zip(clients)
        .map(|(r, c)| (c.id(), Some(*r)))
        .collect()
}

Here we are making use of the as_rows method on Region to split the region we are given (the total available space on the current screen) into evenly sized rows. (There are a number of utility methods on Region to aid in writing layout functions.) We then pair each client with Some(region) to indicate that this is where the client should be placed by the WindowManager. If we provide None for any of the clients, that client will then instead be hidden.

Note, windows are positioned and mapped in order, meaning that later clients will overlap those that have already been positioned if any of the Regions overlap one another.

This simple rows layout is a sub-set of the behaviour provided by the built in side_stack layout (in effect, clamping max_main at 0).

Structs

Layout	Responsible for arranging Clients within a Workspace.
LayoutConf	When and how a Layout should be applied.

Functions

bottom_stack	A simple layout that places the main region at the top of the screen and tiles remaining windows in a single row underneath.
client_breakdown	number of clients for the main area vs secondary
floating	A no-op floating layout that simply satisfies the type required for Layout
monocle	A simple monolve layout that places uses the maximum available space for the focused client and unmaps all other windows.
side_stack	A simple layout that places the main region on the left and tiles remaining windows in a single column to the right.

Type Definitions

LayoutFunc

A function that can be used to position Clients on a Workspace.