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Diffstat (limited to 'lib/gears/wallpaper.lua')
| -rw-r--r-- | lib/gears/wallpaper.lua | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/lib/gears/wallpaper.lua b/lib/gears/wallpaper.lua new file mode 100644 index 0000000..70ecf48 --- /dev/null +++ b/lib/gears/wallpaper.lua @@ -0,0 +1,221 @@ +--------------------------------------------------------------------------- +-- @author Uli Schlachter +-- @copyright 2012 Uli Schlachter +-- @module gears.wallpaper +--------------------------------------------------------------------------- + +local cairo = require("lgi").cairo +local color = require("gears.color") +local surface = require("gears.surface") +local timer = require("gears.timer") +local root = root + +local wallpaper = { mt = {} } + +local function root_geometry() + local width, height = root.size() + return { x = 0, y = 0, width = width, height = height } +end + +-- Information about a pending wallpaper change, see prepare_context() +local pending_wallpaper = nil + +local function get_screen(s) + return s and screen[s] +end + +--- Prepare the needed state for setting a wallpaper. +-- This function returns a cairo context through which a wallpaper can be drawn. +-- The context is only valid for a short time and should not be saved in a +-- global variable. +-- @param s The screen to set the wallpaper on or nil for all screens +-- @return[1] The available geometry (table with entries width and height) +-- @return[1] A cairo context that the wallpaper should be drawn to +function wallpaper.prepare_context(s) + s = get_screen(s) + + local root_width, root_height = root.size() + local geom = s and s.geometry or root_geometry() + local source, target, cr + + if not pending_wallpaper then + -- Prepare a pending wallpaper + source = surface(root.wallpaper()) + target = source:create_similar(cairo.Content.COLOR, root_width, root_height) + + -- Set the wallpaper (delayed) + timer.delayed_call(function() + local paper = pending_wallpaper + pending_wallpaper = nil + wallpaper.set(paper.surface) + paper.surface:finish() + end) + elseif root_width > pending_wallpaper.width or root_height > pending_wallpaper.height then + -- The root window was resized while a wallpaper is pending + source = pending_wallpaper.surface + target = source:create_similar(cairo.Content.COLOR, root_width, root_height) + else + -- Draw to the already-pending wallpaper + source = nil + target = pending_wallpaper.surface + end + + cr = cairo.Context(target) + + if source then + -- Copy the old wallpaper to the new one + cr:save() + cr.operator = cairo.Operator.SOURCE + cr:set_source_surface(source, 0, 0) + cr:paint() + cr:restore() + end + + pending_wallpaper = { + surface = target, + width = root_width, + height = root_height + } + + -- Only draw to the selected area + cr:translate(geom.x, geom.y) + cr:rectangle(0, 0, geom.width, geom.height) + cr:clip() + + return geom, cr +end + +--- Set the current wallpaper. +-- @param pattern The wallpaper that should be set. This can be a cairo surface, +-- a description for gears.color or a cairo pattern. +-- @see gears.color +function wallpaper.set(pattern) + if cairo.Surface:is_type_of(pattern) then + pattern = cairo.Pattern.create_for_surface(pattern) + end + if type(pattern) == "string" or type(pattern) == "table" then + pattern = color(pattern) + end + if not cairo.Pattern:is_type_of(pattern) then + error("wallpaper.set() called with an invalid argument") + end + root.wallpaper(pattern._native) +end + +--- Set a centered wallpaper. +-- @param surf The wallpaper to center. Either a cairo surface or a file name. +-- @param s The screen whose wallpaper should be set. Can be nil, in which case +-- all screens are set. +-- @param background The background color that should be used. Gets handled via +-- gears.color. The default is black. +-- @see gears.color +function wallpaper.centered(surf, s, background) + local geom, cr = wallpaper.prepare_context(s) + surf = surface.load_uncached(surf) + background = color(background) + + -- Fill the area with the background + cr.operator = cairo.Operator.SOURCE + cr.source = background + cr:paint() + + -- Now center the surface + local w, h = surface.get_size(surf) + cr:translate((geom.width - w) / 2, (geom.height - h) / 2) + cr:rectangle(0, 0, w, h) + cr:clip() + cr:set_source_surface(surf, 0, 0) + cr:paint() + surf:finish() +end + +--- Set a tiled wallpaper. +-- @param surf The wallpaper to tile. Either a cairo surface or a file name. +-- @param s The screen whose wallpaper should be set. Can be nil, in which case +-- all screens are set. +-- @param offset This can be set to a table with entries x and y. +function wallpaper.tiled(surf, s, offset) + local _, cr = wallpaper.prepare_context(s) + + if offset then + cr:translate(offset.x, offset.y) + end + + surf = surface.load_uncached(surf) + local pattern = cairo.Pattern.create_for_surface(surf) + pattern.extend = cairo.Extend.REPEAT + cr.source = pattern + cr.operator = cairo.Operator.SOURCE + cr:paint() + surf:finish() +end + +--- Set a maximized wallpaper. +-- @param surf The wallpaper to set. Either a cairo surface or a file name. +-- @param s The screen whose wallpaper should be set. Can be nil, in which case +-- all screens are set. +-- @param ignore_aspect If this is true, the image's aspect ratio is ignored. +-- The default is to honor the aspect ratio. +-- @param offset This can be set to a table with entries x and y. +function wallpaper.maximized(surf, s, ignore_aspect, offset) + local geom, cr = wallpaper.prepare_context(s) + surf = surface.load_uncached(surf) + local w, h = surface.get_size(surf) + local aspect_w = geom.width / w + local aspect_h = geom.height / h + + if not ignore_aspect then + aspect_h = math.max(aspect_w, aspect_h) + aspect_w = math.max(aspect_w, aspect_h) + end + cr:scale(aspect_w, aspect_h) + + if offset then + cr:translate(offset.x, offset.y) + elseif not ignore_aspect then + local scaled_width = geom.width / aspect_w + local scaled_height = geom.height / aspect_h + cr:translate((scaled_width - w) / 2, (scaled_height - h) / 2) + end + + cr:set_source_surface(surf, 0, 0) + cr.operator = cairo.Operator.SOURCE + cr:paint() + surf:finish() +end + +--- Set a fitting wallpaper. +-- @param surf The wallpaper to set. Either a cairo surface or a file name. +-- @param s The screen whose wallpaper should be set. Can be nil, in which case +-- all screens are set. +-- @param background The background color that should be used. Gets handled via +-- gears.color. The default is black. +-- @see gears.color +function wallpaper.fit(surf, s, background) + local geom, cr = wallpaper.prepare_context(s) + surf = surface.load_uncached(surf) + background = color(background) + + -- Fill the area with the background + cr.operator = cairo.Operator.SOURCE + cr.source = background + cr:paint() + + -- Now fit the surface + local w, h = surface.get_size(surf) + local scale = geom.width / w + if h * scale > geom.height then + scale = geom.height / h + end + cr:translate((geom.width - (w * scale)) / 2, (geom.height - (h * scale)) / 2) + cr:rectangle(0, 0, w * scale, h * scale) + cr:clip() + cr:scale(scale, scale) + cr:set_source_surface(surf, 0, 0) + cr:paint() + surf:finish() +end + +return wallpaper + +-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80 |