awesome/lib/gears/shape.lua

198 lines
7.1 KiB
Lua

---------------------------------------------------------------------------
--- 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 g_matrix = require( "gears.matrix" )
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
--- A rounded rectangle with a triangle at the top
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
-- @tparam[opt=5] number corner_radius The corner radius
-- @tparam[opt=10] number arrow_size The width and height of the arrow
-- @tparam[opt=width/2 - arrow_size/2] number arrow_position The position of the arrow
function module.infobubble(cr, width, height, corner_radius, arrow_size, arrow_position)
corner_radius = corner_radius or 5
arrow_size = arrow_size or 10
arrow_position = arrow_position or width/2 - arrow_size/2
cr:move_to(0 ,corner_radius)
-- Top left corner
cr:arc(corner_radius, corner_radius+arrow_size, (corner_radius), math.pi, 3*(math.pi/2))
-- The arrow triangle (still at the top)
cr:line_to(arrow_position , arrow_size )
cr:line_to(arrow_position + arrow_size , 0 )
cr:line_to(arrow_position + 2*arrow_size , arrow_size )
-- Complete the rounded rounded rectangle
cr:arc(width-corner_radius, corner_radius+arrow_size , (corner_radius) , 3*(math.pi/2) , math.pi*2 )
cr:arc(width-corner_radius, height-(corner_radius) , (corner_radius) , math.pi*2 , math.pi/2 )
cr:arc(corner_radius , height-(corner_radius) , (corner_radius) , math.pi/2 , math.pi )
-- Close path
cr:close_path()
end
--- A rectangle terminated by an arrow
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
function module.rectangular_tag(cr, width, height)
cr:move_to(0 , height/2)
cr:line_to(height/2 , 0 )
cr:line_to(width , 0 )
cr:line_to(width , height )
cr:line_to(height/2 , height )
cr:close_path()
end
--- A simple arrow shape
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
-- @tparam[opt=head_width] number head_width The width of the head (/\) of the arrow
-- @tparam[opt=width /2] number shaft_width The width of the shaft of the arrow
-- @tparam[opt=height/2] number shaft_length The head_length of the shaft (the rest is the head)
function module.arrow(cr, width, height, head_width, shaft_width, shaft_length)
shaft_length = shaft_length or height / 2
shaft_width = shaft_width or width / 2
head_width = head_width or width
local head_length = height - shaft_length
cr:move_to ( width/2 , 0 )
cr:rel_line_to( head_width/2 , head_length )
cr:rel_line_to( -(head_width-shaft_width)/2 , 0 )
cr:rel_line_to( 0 , shaft_length )
cr:rel_line_to( -shaft_width , 0 )
cr:rel_line_to( 0 , -shaft_length )
cr:rel_line_to( -(head_width-shaft_width)/2 , 0 )
cr:close_path()
end
--- A squeezed hexagon filling the rectangle
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
function module.hexagon(cr, width, height)
cr:move_to(height/2,0)
cr:line_to(width-height/2,0)
cr:line_to(width,height/2)
cr:line_to(width-height/2,height)
cr:line_to(height/2,height)
cr:line_to(0,height/2)
cr:line_to(height/2,0)
cr:close_path()
end
--- Double arrow popularized by the vim-powerline module
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
-- @tparam[opt=height/2] number arrow_depth The width of the arrow part of the shape
function module.powerline(cr, width, height, arrow_depth)
arrow_depth = arrow_depth or height/2
cr:move_to(0 , 0 )
cr:line_to(width - arrow_depth , 0 )
cr:line_to(width , height/2 )
cr:line_to(width - arrow_depth , height )
cr:line_to(0 , height )
cr:line_to(arrow_depth , height/2 )
cr:close_path()
end
--- An isosceles triangle
-- @param cr A cairo context
-- @tparam number width The shape with
-- @tparam number height The shape height
function module.isosceles_triangle(cr, width, height)
cr:move_to( width/2, 0 )
cr:line_to( width , height )
cr:line_to( 0 , height )
cr:close_path()
end
--- Ajust the shape using a transformation object
--
-- Apply various transformations to the shape
--
-- @usage gears.shape.transform(gears.shape.rounded_bar)
-- : rotate(math.pi/2)
-- : translate(10, 10)
--
-- @param shape A shape function
-- @return A transformation handle, also act as a shape function
function module.transform(shape)
-- Apply the transformation matrix and apply the shape, then restore
local function apply(self, cr, width, height, ...)
cr:save()
cr:transform(self:to_cairo_matrix())
shape(cr, width, height, ...)
cr:restore()
end
local matrix = g_matrix.identity:copy()
rawset(matrix, "_call", apply)
return matrix
end
return module