Since the 1.6 update has resource packs, if you try to put texture packs in your resource pack folder, it will not work, nor will texture packs that you had with your Minecraft launcher with your texture packs from Minecraft 1.5.2, since resource packs are to replace texture packs, texture packs will no longer work, and you would have to do all your hard work making your own texture pack, now you are going to have to do even MORE hard work to make a resource pack.
Since this API system to replace texture packs will come out, to use your texture pack, you would need to convert the texture pack via a tool called Minecraft Texture Ender, which is available from Mojang to convert unstitched texture packs to stitched texture packs.To unstitch the texture pack, you would need a program such as Unstitcher.
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