From fb0c82a79891aaa7dc577194325d46334e286653 Mon Sep 17 00:00:00 2001
From: Emmanuel Lepage Vallee <elv1313@gmail.com>
Date: Mon, 18 Jan 2016 17:20:32 -0500
Subject: [PATCH] gears.shape: Add a new module to make it easier to use shapes

This code is imported from Elv13 config and make it very easy
to create shaped objects.

If accepted upstream, other shapes, such as arrow and powerline
will also be added. This commit introsuce the 2 most common
shapes, rounded rectangle and rounded bar.
---
 lib/gears/init.lua  |  1 +
 lib/gears/shape.lua | 58 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)
 create mode 100644 lib/gears/shape.lua

diff --git a/lib/gears/init.lua b/lib/gears/init.lua
index 3289483ac..fab5d1f52 100644
--- a/lib/gears/init.lua
+++ b/lib/gears/init.lua
@@ -17,6 +17,7 @@ return
     timer = require("gears.timer");
     cache = require("gears.cache");
     matrix = require("gears.matrix");
+    shape = require("gears.shape");
 }
 
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80
diff --git a/lib/gears/shape.lua b/lib/gears/shape.lua
new file mode 100644
index 000000000..dd7594250
--- /dev/null
+++ b/lib/gears/shape.lua
@@ -0,0 +1,58 @@
+---------------------------------------------------------------------------
+--- Module dedicated to gather common shape painters.
+--
+-- It add the concept of "shape" to Awesome. A shape can be applied to a
+-- background, a margin, a mask or a drawable shape bounding.
+--
+-- The functions exposed by this module always take a context as first
+-- parameter followed by the widget and height and additional parameters.
+--
+-- The functions provided by this module only create a path in the content.
+-- to actually draw the content, use cr:fill(), cr:mask(), cr:slip() or
+-- cr:stroke()
+--
+-- In many case, it is necessary to apply the shape using a transformation
+-- such as a rotation. The preferred way to do this is to wrap the function
+-- in another function calling `cr:rotate()` (or any other transformation
+-- matrix)
+--
+-- @author Emmanuel Lepage Vallee
+-- @copyright 2011-2016 Emmanuel Lepage Vallee
+-- @release @AWESOME_VERSION@
+-- @module gears.shape
+---------------------------------------------------------------------------
+
+local module = {}
+
+--- Add a rounded rectangle to the current path
+-- @note If the radius is bigger than either half side, it will be reduced
+-- @param cr A cairo content
+-- @param width The rectangle width
+-- @param height The rectangle height
+-- @param radius the corner radius
+function module.rounded_rect(cr, width, height, radius)
+    if width / 2 < radius then
+        radius = width / 2
+    end
+
+    if height / 2 < radius then
+        radius = height / 2
+    end
+
+    cr:arc( radius      , radius       , radius,    math.pi   , 3*(math.pi/2) )
+    cr:arc( width-radius, radius       , radius, 3*(math.pi/2),    math.pi*2  )
+    cr:arc( width-radius, height-radius, radius,    math.pi*2 ,    math.pi/2  )
+    cr:arc( radius      , height-radius, radius,    math.pi/2 ,    math.pi    )
+
+    cr:close_path()
+end
+
+--- Add a rectangle delimited by 2 180 degree arcs to the path
+-- @param cr A cairo content
+-- @param width The rectangle width
+-- @param height The rectangle height
+function module.rounded_bar(cr, width, height)
+    module.rounded_rect(cr, width, height, height / 2)
+end
+
+return module