Subtitle wordwrap can cause an infinite loop

[Spiky Caterpillar]

Attempting to render excessively long text with layout='subtitle' and no spaces to break on will cause a tight infinite loop.

(Testcase:
    $ x = 30
label wrapfail:
    show expression Text('M'*x,xmaximum=300,yminimum=20,color='#0f0',yalign=0.5,size=15,layout='subtitle')
    "%(x)d"
    $ x += 1
    jump wrapfail
)

The actual loop is in renpy/display/text.py's subtitle_text_layout function. I think the best fix is probably to break words longer than the desired width into single-character tokens; a patch to do so follows. (It does, however, not
generate the optimum layout with the string of Ms - not sure if that's a problem in my change or a problem in the original subtitle layout, but it's better than an infinite loop.)

*** text.py.orig 2009-08-04 17:18:15.000000000 -0700
--- text.py 2009-08-04 18:27:50.000000000 -0700
***************
*** 548,553 ****
--- 548,564 ----
      lines_last = [ ]

      for triples in pars:
+ x = 0
+ newtriples = []
+ while x<len(triples):
+ triplewidth = layout_width([triples[x],],justify)
+ if triplewidth<=width or triples[x][0]!='word':
+ newtriples.append(triples[x])
+ else:
+ for char in triples[x][2]:
+ newtriples.append(('word',triples[x][1],char))
+ x+=1
+ triples = newtriples

          sumwidths = layout_width(triples, justify)
(End patch)

[Tom Rothamel (renpytom)]

This seems as sensible a behavior as any. Could you post your patch as an attachment, as it seems to have been reformatted by launchpad.

[Spiky Caterpillar (spikycaterpillar)]

Here it is.