[2.0.24] Deconstructing lots of platform tiles at once is very slow

[IsaacOscar]

Consider the following pointless platform:

12-11-2024, 15-31-51.png (656.02 KiB) Viewed 90 times

It has a 2×100 column of platform tiles.

Now if I delete all the tiles using alt-d or ctrl-x (it doesn't matter which):

12-11-2024, 15-32-50.png (1.62 MiB) Viewed 90 times

The left half of the column, and the last tile on the bottom-right get instantly deleted, whilst the remaining tiles get marked with a red 'x':

12-11-2024, 15-33-56.png (622.67 KiB) Viewed 90 times

It then stays like that for 20 ticks. Untill finally, the bottom tiles is deleted. The next tile also takes 20 ticks to get deleted.

Now if instead of the above, I only deleted the bottom half of the column (100 instead of 200 tiles), I get the same behaviour, except it only takes 10 ticks to delete each tile.

12-11-2024, 15-39-18.png (1.78 MiB) Viewed 90 times

Halving that again (to 50 tiles) gives 5 ticks.
(Thus deleting platform tiles appears to be an O(n²) operation).

In other words, it is literally faster for the player to delete a bit of the platform, wait for it to finish, then delete more, then to rely on factorio to delete the whole thing in one operation.

Note that I had no FPS/UPS drop doing this.

[Rseding91]

Thanks for the report however this is not a bug. Don’t build that huge stick if you don’t want a huge stick.

[IsaacOscar]

Thanks for the report however this is not a bug. Don’t build that huge stick if you don’t want a huge stick.

Sure, but it's a really annoying performance issue that has make building actual platforms difficult (and not just this test case).
In fact, it's the only performance issue I've had playing space age.