Once more hath I created a new tool. This one is not so big as previous ones, but still very important.
There is Silky Engine, on which where are many interesting visual novels. Some time ago I hath created a script editing tool for it's mes scripts and wrote an article of it... And all the time I through there were good enough tools for it. But I checked and... Some tools can just extract data from it, other (some tool from regonme) can pack, but, alas, without compressing files per LZSS implementation, used in Silky Engine. Therefore files was getting too big and there was no method to create actually normal enough Silky's arc archives.
But that time hath come to the end. I hath tested this LZSS implementation and created SilkyArcTool, by using which thou can both extract and pack Silky archives, using this LZSS compression algorithm (I hath implemented not only decompression, as in many tools, but also a compression algorithm).
Therefore Silky Engine's (and Ai6WIN/Ai5WIN's (probably) .arc archives has fallen completely.
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Updated: AI6WIN (and probably AI5WIN) .arc not supported. Still I have already hacked AI6WIN .arc archives, so tool will be released soon.