"Couldn't write file to disk" when converting from Shadertoy


Hello all,

I’m trying to convert a shader from Shadertoy (I’ve tried several examples and they all give me this error code) and I get an OSX error:

"Error: couldn’t write file to disk “/users/blahblahblah/library/graphics/isf/blahblahblah.fs”

I’m on OSX 10.14.6 Using ISF Editor version 2.9.13

Any recommendations?




  1. In the Finder, use the Go to Folder menu option and enter “~/Library/Graphics”
  2. If there is no folder called “ISF” add one


Thank you so much!! It took me a minute to understand as I got confused at there being essentially 2 library folders. One for the system, and one for the user, and a mystery to me why it’s the user library that’s hidden, and not the system library. But I digress, it took me a while to even find out how to find that folder, but figured it out

(For anybody else out there, you go to your user folder with the house icon, you click the gear inside the finder window and go to view options, and then select the box that says “view library folder” and it becomes visible.

I got it working now! So cool!! I’m going to go plunder Shadertoy now :)

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