Tilemap transformation matrix acting strange

Questions
#1

i’m having really weird behavior loading in tilemaps.
i’m using tiled, exporting to a .lua file
the bitflags for the transformation matrix of tiles seems to be off.
there seems to be an erroneous addition of a flip sometimes

below are some test squares, rows from top to bottom: none, vertical flip, horizontal flip, both flips). columns from left to right: none, rotated clockwise once, twice, three times

how it shows up in tiled (how it should look):
Capture

how it shows up in game (not so good):
Capture2


my code for getting the transform matrix (and tile id too):

local function extracttile(tilenum)
	local tile=bit.band(0xFFFFFFF,tilenum)
	local flags=tilenum-tile
	flags=bit.rshift(flags, 28)
	local rflags=0
	local hf,vf,r9=false,false,false
	hf= (bit.band(flags,8)>1)   --hlfip
	vf= (bit.band(flags,4)>1) --vflip
	r9= (bit.band(flags,2)>1)  --rotation
	
	rflags=(hf and tilemap.H_FLIP or 0) + (vf and tilemap.V_FLIP or 0) + (r9 and tilemap.ROTATE_90 or 0)

	return tile,rflags
end


is the problem with defold not handling transforms correctly or is it with tiled not exporting properly, or is it my code being bad?

#2

ok so for whatever reason, i have to give a tile whenever it is rotated, an additional vertical flip.
unless there’s already a vertical or horizontal flip, in which case i need to give it a horizontal flip
except if there’s both a vertical *and* horizontal flip, in which case i just use a vertical flip again.

why?

#3

No idea. My head hurts trying to make sense of all of the flips and rotations :slight_smile: I suppose it also matter in which order the operations are applied. The flip or the rotation first? Depending on which one is done first the outcome will be different.

#4

I suppose it also matter in which order the operations are applied.

that only applies to tiled, where the order of a flip/rotate will affect the actual tile transform (this is only done, from what i can tell at least, to make it more intuitive to use)
however, the transforms themselves are orderless, both in how they are saved in a tilemap (as a tiled .lua file, the 3 (4) highest bits) and how defold handles transforms (a series of bitflags you add together)