this strange error message always told me that the error is one line after the last line. because the shader worked before (i have no idea what is different with the development engine?) i came to the conclusion that it isn't a bug in the shader. i thought such an error message could be caused by the fact that the string is too long (the fur shader is extremely long) and this could be worked around with an .fx file because maybe it doesn't use the string. it worked!

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these tunnels look great!