Tiling size doesn't always work for aligned tiling

[Dimitar Misev]

Specifying a simple tiling scheme of [0:*,0:*,..] and then limiting it to a tileSize works as expected: tile dimensions are computed properly and the tile sizes do not exceed tileSize.

Specifying a tiling scheme of [0:large_number,0:large_number,...] and then limiting it to a small tileSize doesn't seem to work: the resulting tiles actually get sizes corresponding to the tiling scheme, rather than the tileSize.

Tile sizes should not exceed tileSize.

[Peter Baumann]

hm, question to me is: what is the intended behavior? What you describe seems not entirely wrong, just a decision made on conflicting requirements. Maybe we should we throw an exception at definition time once there are obvious conflicts.

[Dimitar Misev]

According to the tiling paper, the tiling scheme of the generated tiles is accordingly scaled to fit the tileSize.

The tiling scheme basically specifies the geometry of the tiles, and the tile size limits the length of each axis proportionally.

This only happens on 3D+, on 2D it works fine.

Here's an example:

insert into $COLL values marray x in [0:3270, 0:3270, 0:0] values 123c
tiling aligned [0:*,0:*,0:*] tile size 4194304

produces these tiles as expected:

"[1282:2563,0:3270,0:0]",
"[2564:3270,0:3270,0:0]",
"[0:1281,0:3270,0:0]"

However

insert into $COLL values marray x in [0:3270, 0:3270, 0:0] values 123c
tiling aligned [0:4194304,0:4194304,0:4194304] tile size 4194304

produces a different result of single tile, even though it should be exactly same as previously:

"[0:3270,0:3270,0:0]"