Orbital Ion Cannon 1.4.0

The direct damage from the ion cannon blast now only applies within 80% of the full blast radius as defined in the config file. This effectively returns the full damage radius to 20, as it was in version 1.2.3.
All entities within 100% of the blast radius (25 by default) will be instantly set on fire; even if something survives the initial blast, it will continue to burn.
Black plumes of smoke will be emitted from ion cannon blast sites, similar to the smoke emitted by forest fires... and indeed, the blast can now ignite forest fires!

The "Ion Cannons" text-button at the top of the screen has been changed to an icon-button. Upon first update, the icon will shift position slightly; simply click it a couple times to reset the GUI positions.
Added a custom hotkey that you can press to toggle the Ion Cannon GUI rather than click the button. The keybinding is "I" by default; you can edit this in the game controls options.

Auto-targeting stations now scan for targets on a chunk-by-chunk basis, which should vastly improve performance while also eliminating the tendency for multiple stations to needlessly fire on the same target.
This also makes the auto-targeting stations behave more like vanilla radars; now you can monitor their scanning progress on the map as each chunk is revealed.
The range of the auto-targeting station is now represented in chunks (chunks are 32x32 tiles). The new default range is 10 chunks (for a 20x20 chunk scan region).
Each station now scans a new chunk every 4 seconds.

Orbital Ion Cannon 1.3.1

Fixed worm auto-targeting config option.

Orbital Ion Cannon 1.3.0

Updated for Factorio 0.13 (thanks to Danielv123 for assisting).
25% more BOOM: Increased default blast radius from 20 to 25.
Add config option to disable printing messages to the console whenever an ion cannon fires or an auto-targeting station acquires a target.
Added a dark_background_icon to the Targeting Device, to improve visibility in some situations.
"Select Target" should now play more promptly upon grabbing a Targeting Device.
The Auto-Targeting Station no longer prints messages when all ion cannons are on cooldown.
Added an option in config.lua to toggle targeting of both worms & spawners or just spawners only (courtesy of madmaxoft).
Performance optimizations.
Increased default Auto-Targeting range to 400.

Orbital Ion Cannon 1.2.3

Increase default Auto-Targeter range to 250 tiles.
Add Worms as valid targets for Auto-Targeters; Spawners are primary targets, Worms secondary.

Orbital Ion Cannon 1.2.2

Fix compatibility with mods that add an Assembling Machine 4 but don't increase the ingredient_count.

Orbital Ion Cannon 1.2.1

Revert use of the Standard Library's event registry function, as it did not behave as I intended.
Use improved graphics for the Auto-Targeting Station, courtesy of the excellent ExtraChests mod by Qumojo (https://forums.factorio.com/viewtopic.php?f=91&t=19970)

Orbital Ion Cannon 1.2.0

Added an Auto-Targeting Station, a radar-type entity that periodically scans for enemy spawners, and automatically fires an ion cannon if it detects one.
Reduced the overlap the klaxon sound can have when firing multiple ion cannons in succession.
Extended the remote interface to allow firing an ion cannon. See the readme for more modding details.
Changed the default config.lua settings:
Damage increased, heatup time increased, cooldown increased, proximity check disabled, voice style reverted to classic C&C.
These are of course just changes to the defaults, you can change them yourself at any time.
Increased the cost of the ion cannon recipe.
The target location for all ion cannons is now shown on the map (when you press M). This is helpful to identify which spawner an Auto-Targeting Station is firing at -- or to detect enemy target locations in PvP!

Orbital Ion Cannon 1.1.0

The mod is now using the Factorio Standard Library (https://github.com/Afforess/Factorio-Stdlib/wiki).
Added German translation (courtesy of bNarFProfCrazy).
Added two new Announcer voice styles to choose from (similar to the Red Alerts mod): Tiberian Sun EVA & Tiberian Sun CABAL. Select your favorite voice in config.lua.

Orbital Ion Cannon 1.0.9

Version 1.0.0 - November 20, 2015

Initial release, featuring orbital ion cannons that can pretty much obliterate anything you might come across.

Version 1.0.1 - November 20, 2015

"Select Target" no longer plays when all ion cannons are on cooldown.
Added damage amount for each ion cannon blast to config.lua.

Version 1.0.2 - November 22, 2015

Ion Cannons can now be crafted in vanilla Assembling Machine 3s, if there are no other mods installed which enable higher tiers of assembling machines.

Version 1.0.3 - November 22, 2015

Fixed a bug in multiplayer mode.

Version 1.0.4 - November 23, 2015

Added a third GUI state; now, clicking the main Ion Cannon button cycles through Closed, Open (Full), and Open (Compact).
This is helpful if you happen to have lots of ion cannons in orbit and would rather not have the GUI take up half of your screen!

Version 1.0.5 - December 11, 2015

Added an option in config.lua to enable/disable the klaxon sound that plays whenever an ion cannon target is designated.
Added an option in config.lua to adjust ion cannons' heatup time, i.e. the time between target designation and ion cannon blast impact.
Slightly increased the default value of the ion cannon blast radius. (You can of course still change it in config.lua if you want.)
Adjusted minimum base version requirement to >=0.12.17, due to graphical oddities present in lower versions.
Fixed " Unknown key:"entity-name.ion-cannon-target" " in the defeated enemies list; now it explicitly states that this is the number of times an ion cannon was fired.
Both the light generated by an ion cannon blast (best observed at night) and the size of the crater left behind now scale with the blast radius (as set in config.lua).

Version 1.0.6 - January 9, 2016

Multiple forces are now supported. Now, each force can only access the ion cannons they have launched.
Note that if loading a save where ion cannons have already been launched, these ion cannons will be all assigned to the "player" force when updating.
Moved hard-coded text strings out of control.lua into the locale .cfg files. Now all texts in the mod should be localizable into other languages.
The "Select target" notification and switching between closed/full/compact GUI states are now stored on a player-by-player basis.
Added an option in config.lua to disable the check for friendly characters in close proximity to the target zone. It is recommended to disable this check if you are using the "Long Reach" mod.
Added an option in config.lua that controls the minimum time between targeting multiple ion cannons. By changing this value, you can control how often ion cannons are allowed to be fired.

Version 1.0.7 - February 20, 2016

Fixed a bug when another mod created a new force in init.
Updated recipes & technologies to use more new ingredients if Bob's Tech and/or Bob's Electronics mods are installed.
Fixed a rare bug when forces merged.

Version 1.0.8 - February 26, 2016

Added Russian translation (thanks to apriori).
To increase performance, the on_tick function is now only registered upon first launching an ion cannon into orbit - there was no need to run this function in the early game before any ion cannons have been launched.

Version 1.0.9 - March 1, 2016

Properly fixed the technology to include Bob's Science Pack 4 if bobtech is loaded.
Fixed that the mod's on_tick function wasn't getting re-registered when loading a saved game.
Added a remote interface to allow other mods to detect when an ion cannon is targeted.