I have a line I'm styling with line-pattern-file. If I change the pattern file (changing the colour, for example), TileMill refreshes the maps, but the line pattern still has the old colour. The only work-around I've found is to save the file with a new name each time.
Here's the style I'm using:
P.S. – I know I've filed a lot of issues lately. I don't want to give the impression that I dislike TileMill -- I think it's great, but it could be even better.
mapnik caches images. We're working on designing a fix - this is the same reason that shapefiles cannot be edited/refreshed in QGIS while TileMill is running. Another workaround is to restart tilemill, which will clear the cache.
see mapnik/mapnik#1022. closing this one, we can track at mapnik site.
this should be fixed now, will be live in the next version of TileMill.
also clear the mapnik cache in the tile process - refs #1121,#714,#1210,
fix the request method - this finally fixes shapefile mapped memory c…
…learing - refs #1121,#714,#1210,#1278,#1335
still appears in the latest tile mill