[0.9.8] 'Scans' discarded with 3+ radars working together

[Kazuar]

Bug Appearance

When 3 or more radars (deployed in close proximity to another) complete their ‘sector scanning’ progress bar in the same tick, only 2 chunks are revealed, and the remaining scans are discarded (‘used up’ to no effect).

This is slightly annoying, as the radars continue to consume full power nonetheless, an unexpected behavior considering it is a break from the general behavior of other buildings, which either ‘pause’ their progress until it can be applied (e.g. copper smelting furnaces with iron plates clogging the output, assemblers waiting for their products to be unloaded, boilers waiting for temperature to drop below 100°C etc) or who regulate themselves down if full performance can’t be applied (e.g. steam engines).

Reproduction

1) Place 3 or more ‘fresh’ radars in an unpowered location (so all of them have zero progress ‘stored’)
2) Place an electric pole to power the radars so that all of them power up in the same tick (in order to assure they ‘complete’ their scans in the same tick, too)
3) Watch the big map and observe how only 2 chunks are ever revealed, no matter how many radars complete concurringly.

Remarks

I understand this seems to be related to the ‘2 updates/tick’ rule mentioned in this topic (https://forums.factorio.com/forum/vie ... =11&t=1689), however, the bug reported in my topic here is not about map flicker (or map behavior) but rather the fact that the radars behave unexpectedly, and out of order of what is otherwise a uniform, predictable pattern across all structures.

As it is right now, the player is ‘punished’ (power consumption to no effect + the resource cost of effectively dysfunctional radars) for not working around non-documented engine quirks by placing things in a specific order (that construction drones might screw up, anyway).

Ultimately, in my personal opinion, if the radars ‘product’ can not be applied due to the ‘2 updates/tick’ rule, processing of the product ‘sector scan’ should be delayed until the next tick (and the radar ‘paused’ until its ‘output’ is cleared). This delay probably won’t be noticeable to the ‘average’ player.

[edit: added version to title]

[kovarex]

Thank you for the report, I could reproduce the problem (I get just one chunk explored in fact).

It is fixed for 0.10 now