Any disadvantage using a texture pack?

Tom2012

Hi,

I'm using Texture packs for everything at the moment. Sometimes I have a one off sprite and I add it to a texture pack just the same. I could just add it directly to the project. But is there any advantage to this?

I've read up a fair bit on the forums about this but am still unsure what the cons of texture packs are?

Thanks

Tom

zvardin

The only downside I know of is if one texture pack gets so big you're running out of memory. In that case, it may be worthwhile using multiple texture packs. Outside of that though it's a good idea to use texture packs because it should be a lot faster.

ar2rsawseen

1) yes what @zvardin said
2) one texture pack will be slower to load at the start but faster usage in overall scene, while with separate sprite scene will more likely load faster, but might work slower in overall due to texture switching in CPU/GPU.
For example, imagine if CPU/GPU can handle only 1 texture at a time, it will have to be switching between multiple texture. But if everything is in one texture, it is already loaded and can be manipulated.

I would suggest combining texture packs by scenes. That way they will not grow so big, but will have complete advantage of processing, because each scene is displayed separately

Tom2012

Thanks guys - much appreciated.

Makes a lot of sense

aditya

Need to use multiple spritesheets since no image can be greater than 1024x1024. As @zvardin points out here, the device runs out of memory and crashes.

Basically the doc shows the usage as:

TexturePack.new({"1.png", "2.png", "3.png", "4.png")}

Possible to do something like this?

TexturePack.new({"1.txt", "1.png", "2.txt", "2.png", "3.txt", "3.png", "4.txt", "4.png")}

ar2rsawseen

@aditya good try, but nope I don't think so
those should be different texture packs

Kaligula

Hi,

I created simple class if that can help with loading multiple atlases and holds reference of specific image to specific texture pack so you can fetch as with name of image.

-- use as: -- textureCache = TextureAtlasCache.new() -- textureCache:loadAtlases( { "atlas0", "atlas1", "some_other_atlas" } ) -- local img = textureCache:getTextureRegion( "duck.png" ) --[[   This is a class which represents texture cache in images   ]]     local AtlasesPath = "images/atlases/" -- should be change to your path to atlases     TextureAtlasCache = Core.class( Object )       function TextureAtlasCache:init( )   self._atlasHolder, self._atlasKey = {}, {}   end     -- resets state of cache function TextureAtlasCache:reset()   self:unloadAtlas( "all" ) self._atlasHolder, self._atlasKey = {}, {}   end     function TextureAtlasCache:info() return "TextureAtlasCache" end       -- loads all passed atlases to memory and creates links between image name and texturepack -- ( assumption is that name of atlas and txt file have same name and is passed without extension { "first", "second" } for first.png / first.txt and second.png / second.txt function TextureAtlasCache:loadAtlases( atlases)   for i=1, #atlases, 1 do   self:loadAtlas( atlases[ i ] )   end   end       -- load atlas to memory function TextureAtlasCache:loadAtlas( name )   if ( not( self._atlasHolder[ name ] ) ) then self._atlasHolder[ name ] = TexturePack.new( AtlasesPath..name..".txt", AtlasesPath..name..".png", true )   self:loadNames( name )   print( "loaded "..name.." into atlasHolder["..name.."]" ) else print("atlasHolder["..name.."] already in memory") end     end     -- unloads atlas from memory function TextureAtlasCache:unloadAtlas(index)   if index == "all" then   for i,v in pairs( self._atlasHolder ) do   if i ~= 2 then self._atlasHolder[ i ] = nil v = nil end   end   self._atlasKey = {}   else if self._atlasHolder then self._atlasHolder[ index ] = nil     for k, v in pairs ( self._atlasKey ) do if self._atlasKey[ k ] == index then self._atlasKey[ k ] = nil end end   end end collectgarbage() --collectgarbage() print("unloaded atlasHolder["..index.."]")   end       -- create links between images and appropriate texture pack function TextureAtlasCache:loadNames( packName )   local contents, file = "", io.open( AtlasesPath..packName..".txt", "r" )   if (file) then   contents = file:read( "*all" ) file:close()   local entities = self:split( contents, "\n" )   for i=1, #entities, 1 do local temp = self:split( entities[i], "," ) local imageName = temp[ 1 ] if imageName ~= nil then print( "Put in dict: "..imageName ) self._atlasKey[ imageName ] = packName end end end end     -- returns region for image in case that image is appropriate texturepack function TextureAtlasCache:getTextureRegion( texturename )   local key = self._atlasKey[ texturename ] if key ~= nil then   local atlas = self._atlasHolder[ key ] if atlas ~= nil then return atlas:getTextureRegion( texturename ) end end   return nil   end     function TextureAtlasCache:split( str, delim ) -- Eliminate bad cases... if string.find(str, delim) == nil then return { str } end   local result, pat, lastpos = {}, "(.-)" .. delim .. "()", nil for part, pos in string.gfind(str, pat) do table.insert(result, part); lastPos = pos; end   table.insert(result, string.sub( str, lastPos ) )   return result end

PrestonBerger

By ensuring the texture dimensions are a power of two, the graphics pipeline can take advantage of optimizations related to efficiencies in working with powers of two. For example, it can be (and absolutely was several years back before we had dedicated GPUs and extremely clever optimizing compilers) faster to divide and multiply by powers of two. Working in powers of two also simplified operations within the pipeline, such as computation and usage of mipmaps (a number that is a power of two will always divide evenly in half, which means you don't have to deal with scenarios where you must round your mipmap dimensions up or down).