Can now also be used outside of LÖVE, in a low capacity.

spritesheet.lua

@@ -10,6 +10,16 @@ local error, error_internal do
     end
 end
 
+--------------------------------------------------------------------------------
+-- Checks that LÖVE is defined; if not, run in information loading
+-- mode only.
+
+local define_love = true
+if type(love) ~= 'table' then
+    io.stderr:write '[Spritesheet]: Loaded in non-LÖVE environment. Can still load spritesheet data,\n               but image drawing methods will not be defined.\n'
+    define_love = false
+end
+
 --------------------------------------------------------------------------------
 -- Util
 
@@ -17,8 +27,19 @@ local function calculate_animation_duration (self, frame_i)
     local frame_i = frame_i or math.huge
     assert(type(self) == 'table')
     assert(type(frame_i) == 'number')
+
+    -- If time_total is provided, return that.
+    if self.time_total then
+        assert(self.time == nil)
+        self.time = self.time_total/#self
+        return self.time_total
+    end
+
     -- Easy if number
-    if type(self.time) == 'number' then  return math.min(#self, frame_i) * self.time  end
+    if type(self.time) == 'number' then
+        return math.min(#self, frame_i) * self.time
+    end
+
     -- Sum if table
     local sum = 0
     for i = 1, math.min(#self, frame_i) do  sum = sum + self.time[i]  end
@@ -51,6 +72,8 @@ function Sprite.new (quad, imagesheet)
     return setmetatable({ quad = quad, imagesheet = imagesheet, is_sprite = true }, Sprite)
 end
 
+if define_love then
+
 function Sprite:generateImage ()
     local imagesheet, quad  =  self.imagesheet, self.quad
     self.func = function (x, y)
@@ -75,6 +98,8 @@ function Sprite:getSheetDimensions()
     return self.imagesheet.image:getDimensions()
 end
 
+end
+
 setmetatable(Sprite, {__call = function(_, ...) return Sprite.new(...) end})
 
 --------------------------------------------------------------------------------
@@ -85,25 +110,26 @@ local Animation = {}
 
 function Animation.new (self)
     assert(type(self) == 'table')
-    assert(type(self.time) == 'table' or type(self.time) == 'number' and self.time > 0)
+    assert(type(self.time) == 'table' or type(self.time) == 'number' and self.time > 0 or type(self.time_total) == 'number')
     assert(#self > 0)
-    assert(type(self.time) == 'number' or #self == #self.time)
+    assert(type(self.time) == 'number' or type(self.time_total) == 'number' or #self == #self.time)
-
+    if self.time_total then  assert(self.time == nil)  end
     assert(self.wrap == nil or self.wrap == true or self.wrap == false)
 
     local  self = setmetatable(self, Animation)
            self.duration      =  calculate_animation_duration(self)
            self.is_animation  =  true
+
     -- Contact frame?
     if self.contact_frame then
-		-- why was this minus one? It screwed up the audio.
-        --self.contact_time  =  calculate_animation_duration(self, self.contact_frame - 1)
         self.contact_time  =  calculate_animation_duration(self, self.contact_frame)
     end
     --
     return self
 end
 
+if define_love then
+
 function Animation:generateImage ()
     self.func = function (x, y, t)
         t  =  t or 0
@@ -138,6 +164,8 @@ function Animation:getSheetDimensions()
     return self.imagesheet.image:getDimensions()
 end
 
+end
+
 setmetatable(Animation, {__call = function(_, ...) return Animation.new(...) end})
 
 --------------------------------------------------------------------------------
@@ -152,7 +180,7 @@ local function calculate_frame_times (time_list, nr_frames)
     assert(type(time_list) == 'table' or type(time_list) == 'number')
     assert(type(nr_frames) == 'number')
 
-    local frame_times = { [0] = -math.huge }
+    local frame_times = { [0] = -math.huge, orig = not define_love and time_list or nil }
 
     if type(time_list) == 'number' then
         for i = 1, nr_frames do
@@ -168,27 +196,33 @@ local function calculate_frame_times (time_list, nr_frames)
     return frame_times
 end
 
-local function load_quads (image, quad_data, imagesheet)
+local function load_quads (_, _, quad_data, imagesheet)
-    assert(image.typeOf and image:typeOf('Image'))
+    assert(type(imagesheet) == 'table')
-    assert(type(quad_data) == 'table')
+    assert(type(imagesheet.tiles_per_row)    == 'number')
+    assert(type(imagesheet.tiles_per_column) == 'number')
 
-    local image_width, image_height  = image:getDimensions()
+    local  tile_width,  tile_height  = imagesheet.tile_width, imagesheet.tile_height
-    local  tile_width,  tile_height  = quad_data.tile_width, quad_data.tile_height
+    local tiles_per_row  =  imagesheet.tiles_per_row
-    local tiles_per_row  =  image_width/tile_width
+    local max_quad_id    =  tiles_per_row * imagesheet.tiles_per_column - 1
-    local max_quad_id   =  tiles_per_row * (image_height/tile_height) - 1
     local quad_cache = {}
 
     local function quad_from_id (id)
         -- Error checking
         if type(id) ~= 'number' then  error('All quad ids must be natural numbers, but one was %s (%s)', id, type(id))  end
-        if id ~= math.floor(id) then  error('All quad ids must be natural numbers, but one was %03.03f (floating point number)', id)  end
+        if id % 1 ~= 0          then  error('All quad ids must be natural numbers, but one was %03.03f (floating point number)', id)  end
         if not (0 <= id and id <= max_quad_id) then  error('All quad ids must - for this spritesheet ("%s") - be natural numbers equal/below %i, but one was %s = 0x%X', imagesheet.filename, max_quad_id, id, id)  end
 
         -- Calculate
-        if not quad_cache[id] then
+        local quad = quad_cache[id]
-            quad_cache[id] = love.graphics.newQuad((id%tiles_per_row)*tile_width, math.floor(id/tiles_per_row)*tile_height, tile_width, tile_height, image_width, image_height)
+        if quad == nil then
+            if define_love then
+                quad = love.graphics.newQuad((id%tiles_per_row)*tile_width, math.floor(id/tiles_per_row)*tile_height, tile_width, tile_height, imagesheet.width, imagesheet.height)
+            else
+                quad = { id = id, (id%tiles_per_row)*tile_width, math.floor(id/tiles_per_row)*tile_height, tile_width, tile_height }
             end
-        return quad_cache[id]
+            quad_cache[id] = quad
+        end
+        return quad
     end
 
     local function visit_animation (t)
@@ -203,7 +237,7 @@ local function load_quads (image, quad_data, imagesheet)
         return Sprite(quad_from_id(n), imagesheet)
     end
 
-    local function visit_node (t)
+    local function visit_node (t, already_seen)
         assert(type(t) == 'table')
 
         for key, val in pairs(t) do
@@ -211,13 +245,15 @@ local function load_quads (image, quad_data, imagesheet)
             if val_type == 'number' then
                 t[key] = visit_quad(val)
             elseif val_type == 'table' then
-                local  visit_func = val.is_animation and visit_animation or visit_node
+                local  visit_func = rawget(val,'is_animation') and visit_animation or visit_node
-                       visit_func(val)
+                       visit_func(val, already_seen)
             end
         end
 
+        if type(error) == 'table' and define_love then
             error.strict_table(t)
         end
+    end
 
     assert(type(quad_data) == 'table')
     assert(type(quad_data.tile_names) == 'table')
@@ -232,7 +268,14 @@ local function load_quad_data (filename)
 
     -- Attempt to load file
     for filetype in pairs(SPRITESHEET_DATA_FILETYPES) do
-        local chunk, error_msg = love.filesystem.load(filename..'.lua')
+
+        local chunk, error_msg
+        if define_love then
+            chunk, error_msg  =  love.filesystem.load(filename..'.lua')
+        else
+            chunk, error_msg  =  loadfile(filename..'.lua')
+        end
+
         if chunk then
             local data  =  setfenv(chunk, SPRITESHEET_ENV)()
 
@@ -292,25 +335,36 @@ function SpriteSheet.new (filename)
     -- spriteimage itself if you can, as it will silently ignore
     -- several errors.
 
+    local img, width, height
+    if define_love then
+        img  =  love.graphics.newImage(filename..'.png')
+        width, height  =  img:getDimensions()
+    else
+        img     =  require 'imlib2'.image.load(filename..'.png')
+        width   =  img:get_width()
+        height  =  img:get_height()
+    end
+
     -- Set info
     local  self = setmetatable({}, SpriteSheet)
            self.filename     = filename
-           self.image        = love.graphics.newImage(filename..'.png')
+           self.image        = img
+           self.width        = width
+           self.height       = height
            self.origin_x     = 0
            self.origin_y     = 0
 
     -- TODO: Give warning/error due to rounding down.
-    quad_data.tile_width    =  quad_data.tile_width  or math.floor(self.image:getWidth()  / quad_data.tiles_per_row)
+    self.tiles_per_row    = quad_data.tiles_per_row     or math.floor(width  / quad_data.tile_width)
-    quad_data.tile_height   =  quad_data.tile_height or math.floor(self.image:getHeight() / quad_data.tiles_per_column)
+    self.tiles_per_column = quad_data.tiles_per_column  or math.floor(height / quad_data.tile_height)
-    print(self.tile_width, self.tile_height)
 
-    self.tile_width    =  quad_data.tile_width
+    self.tile_width    =  quad_data.tile_width  or math.floor(width  / self.tiles_per_row)
-    self.tile_height   =  quad_data.tile_height
+    self.tile_height   =  quad_data.tile_height or math.floor(height / self.tiles_per_column)
 
     -- Error checking
     do
-        local rem_width  = self.image:getWidth()  % self.tile_width
+        local rem_width  = width  % self.tile_width
-        local rem_height = self.image:getHeight() % self.tile_height
+        local rem_height = height % self.tile_height
         if not quad_data.force_uneven_tile_size and (rem_width ~= 0 or rem_height ~= 0) then
             local s = ('Bad spritesheet "%s". Image size (%i, %i) must be dividable by tile size (%i, %i)')
                        :format(filename, self.image:getWidth(), self.image:getHeight(), self.tile_width, self.tile_height)
@@ -326,7 +380,7 @@ function SpriteSheet.new (filename)
     end
 
     -- Import quads into SpriteSheet
-    self.quads = load_quads(self.image, quad_data, self)
+    self.quads = load_quads(width, height, quad_data, self)
     if rawget(self.quads, 'is_sprite') or rawget(self.quads, 'is_animation') then
         self.only_quads = self.quads
     else
@@ -344,15 +398,19 @@ function SpriteSheet:setOrigin (ox, oy, mode)
     assert(type(ox) == 'number')
     assert(type(oy) == 'number')
 
+   self.origin_orig  = { ox, oy, mode }
+
     if mode == 'absolute' then
         self.origin_x = ox
         self.origin_y = oy
     elseif mode == 'relative' or mode == nil then
-        self.origin_x = self.tile_width * ox
+        self.origin_x = math.floor(self.tile_width  * ox)
-        self.origin_y = self.tile_height * oy
+        self.origin_y = math.floor(self.tile_height * oy)
     else
         error('Unknown origin mode %s (%s)', mode, type(mode))
     end
+    assert(self.origin_x % 1 == 0)
+    assert(self.origin_y % 1 == 0)
 end
 
 function SpriteSheet:getQuadKeys ()