Performance improvements for fixed resolution buffer

[astrofrog]

Work in progress, but can already be tested out.

[astrofrog]

@dhomeier - do you understand the ruff issue here?

[Carifio24]

@dhomeier can correct me if I'm wrong, but I think what it wants is

# `value` is a bad variable name but I don't know what this thing is
for chid, value in PIXEL_CACHE.items():
   if value['hash'] == current_pixel_hash:
       for ipix, pix in enumerate(data.pixel_component_ids):
           if (
                   ipix not in matching_pixel_cache and
                   ipix in value and
                   value[ipix]['bounds'] == bounds
           ):
               matching_pixel_cache[ipix] = value[ipix]

rather than (what is currently is):

for chid in PIXEL_CACHE:
   if PIXEL_CACHE[chid]['hash'] == current_pixel_hash:
         for ipix, pix in enumerate(data.pixel_component_ids):
             if (
                     ipix not in matching_pixel_cache and
                     ipix in PIXEL_CACHE[chid] and
                     PIXEL_CACHE[chid][ipix]['bounds'] == bounds
             ):
                 matching_pixel_cache[ipix] = PIXEL_CACHE[chid][ipix]

[dhomeier]

@dhomeier can correct me if I'm wrong, but I think what it wants is

I can only agree ;-)

[dhomeier]

actually I am surprised Ruff does not complain now that chid is never used – or suggested to use PIXEL_CACHE.values() in the first place... 😂

[astrofrog]

Oh yeah, we should fix that, we should just use .values()...