annoyments
catch exceptions in worker threads (eg: disk full)
figure out where rare libpango segfault is coming from - threading?
enhancements
navigation
configurable zoom mode: center on click vs expand about click
continuous zoom mode while button is pressed
undo/history tree navigation
log annotation and search
log browser view with filtering
log level settings (Set Loggable ?)
persistence
image save as png (or ppm?) when done
save/load viewing parameters in a common plain text format
colouring
multiple colouring modes - minimal / rainbow / hypertile
gui for each colouring mode with appropriate persistence
memory cache
option for maximum memory cache size
warn when memory cache is not enough for window settings
memory cache model - LRU or similar?
disk cache
option for maximum disk cache size
option to disable disk cache for casual exploratory browsing
disk cache management: keep most expensive vs most used?
tile usage statistics database
tile renderer
compute tile cost metrics (iteration stats, boundary size, bit bepth)
which quadrants are interior/exterior etc
re-use pixels from parent/child tiles in renderer
don't compute known-interior tiles
features
scan whole image for atoms, subdivide for more
draw internal rays in feature overlay
feature database - try lookup before calculating, cache results
algorithms
child finding algorithm
parent finding algorithm - need to research
box counting fractal dimension estimates
non-slow angled internal address to external angle
misc
tiled rendering mode for huge images without seams
scripting
helper library for using GHCI via fifo to gruff exe
internal
source code documentation