river-layout: create and implement protocol

Replace the current layout mechanism based on passing args to a child
process and parsing it's stdout with a new wayland protocol. This much
more robust and allows for more featureful layout generators.

Co-authored-by: Isaac Freund <ifreund@ifreund.xyz>

3 files changed, 33 insertions, 138 deletions

diff --git a/doc/river-layouts.7.scd b/doc/river-layouts.7.scd
deleted file mode 100644
index 6b76846..0000000
--- a/doc/river-layouts.7.scd
+++ /dev/null
@@ -1,86 +0,0 @@
-RIVER-LAYOUTS(7) "github.com/ifreund/river"
-
-# NAME
-
-river-layouts - Details on layout generators for river
-
-# DESCRIPTION
-
-River can use external window management layouts. To get such a layout, river
-will run an executable and parse its output. This document outlines how such a
-layout generator interacts with river.
-
-# INPUT
-
-When running the executable, river will provide it with five parameters which
-are appended to the end of the command in the following order:
-
-. The amount of visible clients (integer)
-. The amount of views dedicated as main (integer)
-. The screen size multiplier for the main area (float between 0.0 and 1.0)
-. The useable width of the output (integer)
-. The useable height of the output (integer)
-
-A layout generator may choose to ignore any of these values except
-for the first one.
-
-# OUTPUT
-
-River expects four integer values for each window: The x position, the y
-position, the width and the height. These must be separated by spaces. A window
-configuration having fewer or more than four values is an error and will cause
-river to fall back the full layout.
-
-A layout generator needs to output position and size for every visible window.
-The window configurations are separated by a newline. Too few or too many
-outputted window configurations is an error and will cause river to fall back
-to the full layout.
-
-River will apply the position and dimensions in the order they are outputted to
-the visible windows in the stack from top to bottom.
-
-The output of a layout generator is not required to remain the same when called
-with identical parameters. Layouts are allowed to also depend on external
-factors or be completely random.
-
-# WINDOW DIMENSIONS and POSITION
-
-Layout generators are not supposed to include padding or leave space for window
-borders. The window dimensions will be shrunk by river to make space for these.
-River enforces a minimal window width and height of 50.
-
-Layout generators operate on a special coordinate grid from 0 to the maximum
-useable width or height of an output with the coordinate 0-0 being positioned
-at the top-left corner of the useable area of an output. While layout
-generators are free to place windows everywhere (including coordinates below
-zero or above the maximum width or height of an output), beware that the
-relative positioning of this grid on the screen can not be expected to remain
-constant. River applies an offset to window positions, depending on outer
-padding and the presence of desktop widgets like bars. Layout generators can
-therefore not position windows at exact screen coordinates.
-
-Layout generators are not required to make use of the entire available space.
-Windows may overlap.
-
-# EXAMPLE
-
-Below is an example output of a layout generator for four visible windows. In
-this example layout all four windows have a size of 500 by 500 and are arranged
-in a grid.
-
-```
-0 0 500 500
-500 0 500 500
-0 500 500 500
-500 500 500 500
-```
-
-# AUTHORS
-
-Maintained by Isaac Freund <ifreund@ifreund.xyz> who is assisted by open
-source contributors. For more information about river's development, see
-<https://github.com/ifreund/river>.
-
-# SEE ALSO
-
-*river*(1), *riverctl*(1), *rivertile*(1)
diff --git a/doc/riverctl.1.scd b/doc/riverctl.1.scd
index 46dd3a1..0d17e44 100644
--- a/doc/riverctl.1.scd
+++ b/doc/riverctl.1.scd
@@ -38,29 +38,6 @@ over the Wayland protocol.
 *focus-view* *next*|*previous*
 	Focus the next or previous view in the stack.
 
-*layout* *full*|_command_
-	Provide a command which river will use for generating the layout
-	of non-floating windows on the currently focused output. See
-	*river-layouts*(7) for details on the expected formatting of the
-	output of layout commands. Alternatively, “full” can be given
-	instead of a command to cause river to use its single internal layout,
-	in which windows span the entire width and height of the output.
-
-*mod-main-count* _integer_
-	Increase or decrease the number of "main" views which is relayed to the
-	layout generator. _integer_ can be positive or negative. Exactly how
-	"main" views are display, or if they are even displayed differently
-	from other views, is left to the layout generator.
-
-*mod-main-factor* _float_
-	Increase or decrease the "main factor" relayed to layout
-	generators. _float_ is a positive or negative floating point number
-	(such as 0.05). This value is added to the current main factor which
-	is then clamped to the range [0.0, 1.0]. The layout generator is
-	free to interpret this value as it sees fit, or ignore it entirely.
-	*rivertile*(1) uses this to determine what percentage of the screen
-	the "main" area will occupy.
-
 *move* *up*|*down*|*left*|*right* _delta_
 	Move the focused view in the specified direction by _delta_ logical
 	pixels. The view will be set to floating.
@@ -264,16 +241,10 @@ A complete list may be found in _/usr/include/linux/input-event-codes.h_
 	Setting _step-size_ to 1.0 disables transitions fully regardless of
 	the value of _delta-t_.
 
-*outer-padding* _pixels_
-	Set the padding around the edge of the screen to _pixels_.
-
 *set-repeat* _rate_ _delay_
 	Set the keyboard repeat rate to _rate_ key repeats per second and
 	repeat delay to _delay_ milliseconds.
 
-*view-padding* _pixels_
-	Set the padding around the edge of each view to _pixels_.
-
 *xcursor-theme* _theme_name_ [_size_]
 	Set the xcursor theme to _theme_name_ and optionally set the _size_.
 	The theme of the default seat determines the default for Xwayland
@@ -309,6 +280,28 @@ River declares certain default options for all outputs.
 	Changing this option changes the title of the wayland and X11 backend
 	outputs.
 
+*layout* (string)
+	The layout namespace used to determine which layout should arrange this
+	output. If set to null or no layout with this namespace exists for this
+	output, the output will enter floating mode. Defaults to null.
+
+*main_amount* (uint, optional hint for layouts)
+	An arbitrary positive integer indicating the amount of main views. Defaults
+	to 1.
+
+*main_factor* (float, optional hint for layouts)
+	A floating point numger indicating the relative size of the area reserved
+	for main views. Note that layouts commonly expect values between 0.1 and 0.9.
+	Defaults to 0.6.
+
+*view_padding* (uint, optional hint for layouts)
+	A positive integer indicating the padding in of pixels between / around
+	views. Defaults to 10.
+
+*outer_padding* (uint, optional hint for layouts)
+	A positive integer indicating the padding in of pixels around the layut.
+	Defaults to 10.
+
 # EXAMPLES
 
 Bind bemenu-run to Super+P in normal mode:
@@ -325,4 +318,4 @@ source contributors. For more information about river's development, see
 
 # SEE ALSO
 
-*river*(1), *river-layouts*(7), *rivertile*(1)
+*river*(1), *rivertile*(1)
diff --git a/doc/rivertile.1.scd b/doc/rivertile.1.scd
index f77c177..cbf8f32 100644
--- a/doc/rivertile.1.scd
+++ b/doc/rivertile.1.scd
@@ -6,32 +6,19 @@ rivertile - Tiled layout generator for river
 
 # SYNOPSIS
 
-*rivertile* *left*|*right*|*top*|*bottom* [args passed by river]
+*rivertile*
 
 # DESCRIPTION
 
-*rivertile* is a layout generator for river. It produces tiled layouts with
-split main/secondary stacks in four configurable orientations.
+*rivertile* is a layout client for river. It provides four tiled layouts per
+output with split main/secondary stacks with the main area in different
+positions.
 
-# OPTIONS
+The namespaces of the four layouts are "tile-top", "tile-right", "tile-bottom"
+and "tile-left", corresponding to the position of the main area.
 
-*left*
-	Place the main stack on the left side of the output.
-
-*right*
-	Place the main stack on the right side of the output.
-
-*top*
-	Place the main stack at the top of the output.
-
-*bottom*
-	Place the main stack at the bottom of the output.
-
-# EXAMPLE
-
-Set river's layout to *rivertile*'s *left* layout using riverctl
-
-	riverctl layout rivertile left
+*rivertile* uses the *main_amount*, *main_factor*, *view_padding* and
+*outer_padding* options.
 
 # AUTHORS
 
@@ -41,4 +28,5 @@ source contributors. For more information about river's development, see
 
 # SEE ALSO
 
-*river-layouts*(7), *river*(1), *riverctl*(1)
+*river*(1), *riverctl*(1)
+