Files must be loaded inside setup() or after it has been called

[GoToLoop]

@quark

Images have to be loaded during or after setup()…

Actually they can be loaded during settings():

[SOLVED] Image() nullPtrException

Actually anything related to sketchPath already works as soon as settings(). Same for args[].

File Listing Order

Your sketch is buggy! You’re calling dataFile() before settings()! The private system field PApplet::sketchPath is initialized just before settings() is called back btW. Processing.GitHub.io/processing-javadocs/core/processing/core/PApplet.html#sketchPath--

dataPath() problem under Mac OS X

Anything related to sketchPath is safe in settings() already.