Hi,
Philipp Borgers wrote:
What if we disable directory hashing but use meta tiling? Is this use
case intended?
Everybody uses meta tiles nowadays. This means that the last item of the
hash quintuplet is somewhat degraded in that it only has one of the four
values 0x00, 0x08, 0x80, 0x88 - whereas without metatiles you would see
all 256 possible combinations there.
In theory the computation should map METATILE * METATILE tiles to one
meta file? Which should result for x in [0,7] and y in [0,7] in the new
values z/0/0.meta and for x in[8,15] and y in [8,15] in the values
z/1/1.meta and so on. I should try to divide the input by METATILE if
I'm right.
Now you've lost me. What this computation basically does is, it takes a
20-bit x value and a 20-bit y value (the coordinates of the tile):
xxxxxxxxxxxxxxxxxxxx
yyyyyyyyyyyyyyyyyyyy
(for 40 bits altogehter) and morphs that into a series of five 8-bit
values (again 40 bits), intermingling components of x and y:
xxxxyyyy xxxxyyyy xxxxyyyy xxxxyyyy xxxxyyyy
This computation, and the resulting file names, are the same for
metatile and non-metatile mode, except that in single tile mode, the
file name of the tile is
xxxxyyyy/xxxxyyyy/xxxxyyyy/xxxxyyyy/xxxxyyyy.png
(of course with the xxxxyyyy replaced by matching integer numbers 0-255)
whereas in metatile mode, the file name of the metatile is
xxxxyyyy/xxxxyyyy/xxxxyyyy/xxxxyyyy/x000y000.meta
and the three least significant bits of x and y make up the offset
inside the metatile.
Bye
Frederik
--
Frederik Ramm ## eMail [email protected] ## N49°00'09" E008°23'33"
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