Alien Swarm: Reactive Drop News

We've released a hotfix with the following changes:

• Fixed a crash related to bounty notifications on the main menu. (hotfix went out shortly after midnight UTC on Feburary 1st)
  
• Fixed bounty notifications duplicating the first mission in a group instead of showing all missions together in one notification. (hotfix went out shortly after midnight UTC on Feburary 1st)
  
• Fixed low frame rate or stuttery alien animations.
  
• Fixed aliens being affected by incendiary mines more often than they should be due to lag compensation.
  
• Fixed parasites moving much more than intended while infesting.
  
• Fixed cl_alien_extra_interp being able to be set to a negative value.
  
• Grubs no longer block movement for entities such as doors.
  

This month's update includes some large changes to Heroes of the Interstellar Armed Forces, as well as some balance changes for the Infection Deathmatch mode and several other fixes.

[h2]A note on Lag Compensation[/h2]
The internet doesn't transmit information instantly. Information can only travel at the speed of light, and sometimes the speed of light is just too slow. For example, if a player from Frankfurt joins a lobby hosted in Beijing, even if their computers were directly connected by a very long wire, information would take 50 milliseconds to get from Frankfurt to Beijing and back. In reality, the information needs to travel much further than the 15500 km round trip because the information doesn't move in a straight line.

When you fire a bullet, the information travels a long distance through complicated circuits before it even leaves your computer, and then it spends time traveling through a series of other computers before it finally reaches the one hosting the lobby. But that's not the end of the journey. Once the lobby host has figured out what your bullet did, that information needs to travel back to you and every other player in your lobby. By the time your bullet reaches the lobby host, the alien you were shooting might have moved! But game engines have a few tricks up their sleeves to hide this from you, and because they can't shorten the physical distance the information needs to travel, they do something easier: time travel!

The information about the bullet you fired doesn't wait until it gets to the host and back before it shows something on your screen. First, the game running on your computer pretends the information about the bullet made a round trip to the host instantly. This is called "prediction" because the game "predicts" what the host will say happened. Prediction is shown in red in the images below.

Second, when the information about the bullet reaches the host, the characters in the game move back in time to check where your bullet would have hit. This is called "lag compensation", and is shown in blue in the images below.

Alien Swarm and Alien Swarm: Reactive Drop (prior to this update) lag compensation algorithm, shown with 300ms simulated round trip ping and default settings.

That's not good! If the drone hadn't been moving toward Vegas, he would have completely missed the shot! The lobby host rewound time, but it didn't do a very good job.

Here's what that shot will look like after this update:

Alien Swarm: Reactive Drop (as of this update) lag compensation algorithm, shown with 300ms simulated round trip ping and default settings.

Much better! If you have a configuration that sets cl_lagcompensation 0, we recommend removing that command as it means the lobby host won't time travel at all when you fire a bullet. The hotfix a week ago inadvertently marked cl_lagcompensation as a cheat; it can now be changed freely when not connected to a lobby.

Want to try it out for yourself? Use the newly-added sv_showimpacts 1 command.

[h2]Missions[/h2]

• Tears for Tarnor: Oasis Colony Spaceport: Fixed a piece of the ceiling being solid to grenades near the security office and metal detectors.
  
• Tears for Tarnor: Oasis Colony Spaceport: Made a ceiling between the hangar and the baggage claim fade out sooner to be less distracting.
  
• Added a workaround for missing sounds in the workshop mission The Gauntlet: Arctic.
  

[h2]Weapons[/h2]

• Fixed an animation issue causing aim to shift to the right shortly after the reload animation started, causing missed shots after successful fast reloads on weapons like the Precision Rail Rifle.
  
• Fixed newly unlocked weapons having their "new" marker removed by unlocking another weapon and then closing and reopening the game rather than only removing it when the weapon is selected in briefing as intended.
  

[h2]Lobby[/h2]

• Leader and kick votes are no longer reset on instant restart.
  
• Prevented instant restart from being used more than once every 3 seconds (asw_instant_restart_cooldown). Does not apply to instant restarts performed after the mission complete/failed screen starts fading in.
  
• Fixed a visual bug causing the challenge to appear to be changed to "cmd_change_challenge" when exiting the challenge selection submenu immediately after opening it in the create lobby screen.
  

[h2]Misc[/h2]

• Added a notifications list and filtering settings to the main menu.
  
• Added support for bold and italic text in inventory item descriptions in-game.
  
• Added rd_vindicator_fire_rate. If 0, it will use the previous behavior of inheriting its fire rate from the shotgun.
  
• Fixed medics having a 1-in-25 chance of shouting that they were out of meds when using the "Zing!" chat wheel command.
  
• Fixed a rare crash that could happen after stats were recorded at the end of a mission related to the upcoming crafting materials beta.
  

[h2]Infection Deathmatch Challenge[/h2]

• Rifle grenade damage bonus is now calculated after the knockback force is calculated.
  
• Decreased rifle grenade damage.
  
• Massively increased rockets' knockback force.
  
• Increased rocket damage.
  
• Damage taken during the preparation phase is now immediately healed.
  
• Humans' burning damage against zombies now receives damage bonus regardless of whether the source of the burn is an incendiary mine.
  
• Constructed sentries are now deleted immediately.
  
• Allowed the server console (and challenge scripts) to use the deathmatch game mode console commands (in addition to the lobby leader).
  

Starting in Season 20 (February 2024), Heroes of the Interstellar Armed Forces is gaining two new sources of points. Additionally, we are updating the score multipliers of nearly every mission and many challenges.

[h2]What's Heroes of the Interstellar Armed Forces?[/h2]
Heroes of the Interstellar Armed Forces (HoIAF) is a monthly competition to complete as many difficult missions as possible on participating servers (marked with an 🏅 icon in the lobby list).

You earn more points for harder missions, difficulty settings, and challenges, and for marines in your squad surviving to the end if hardcore friendly fire is enabled. At the end of the month, everyone who participated receives a medal, with special medals going to the players in the top 20 and top 100.

You can display medals on your Steam profile the same way you would display any other item in your inventory, as well as equip up to 3 medals on your Commander Profile in-game. Medals are also available from many other sources. Check out the guides on the Steam Community Hub to find out more!

[h2]Scoring Multiplier Updates[/h2]
109 of the 133 rated missions and 28 of the 76 rated challenges have received scoring changes.

In most cases, the difference between challenge score multipliers has been reduced and the difference between mission score multipliers has increased.

The full list of modifier changes is available on the Reactive Drop developer website.

[h2]Personal Best Scores[/h2]
Starting in Season 20 (February 2024), your personal best score for each mission will earn you bonus points towards your season score. Your 5 best scores contribute the most, with each group of 5 scores afterwards contributing half as much.

The point bonuses are generous. For example, if your best single mission score is 500 points, you'll gain nearly one hundred thousand points towards your season score. If you manage to beat your score by 100 points (600 total), you'll gain an additional nearly forty thousand points.



If you want to stay ahead in future seasons, you'll need to hone your skills at a multitude of missions, and super-high scores in endless missions are now worth far more than the points they give directly.

[h2]Mission Bounties[/h2]
It's not just the high-scorers who are getting a bonus this season! A few times per day, the Interstellar Armed Forces will provide bounties for completing specific missions. You can find these in the notifications area on the main menu, and the missions with bounties you haven't claimed are also marked in the mission chooser while you're connected to a participating server.



Bounties grant points for the successful completion of a mission regardless of difficulty settings or challenges. That means that if you were previously getting a measly 1 point per mission on Easy, you can now earn hundreds or thousands of points a few times per day.

Bounties are created every 8 hours and last for 24 hours. Each set of bounties is either a campaign of 3 to 9 missions or 5 to 6 assorted missions. Bounties do not span multiple seasons, so there is a period at the start of a season with fewer than 3 active sets of bounties and bounties at the end of a season are shorter than 24 hours. Each bounty mission can be completed independently. If you don't want to see information about bounties on the main menu, you can disable the notifications using the button at the bottom of the notifications list.

Happy new year! This month's update contains fixes for controller issues, updates to the Infection deathmatch challenge, and a few miscellaneous fixes and new features.

[h2]Official Missions[/h2]

• BioGen Corporation: Operation X5: Fixed a door that was inadvertently classified as a ladder.
  
• BioGen Corporation: Invisible Threat: Fixed speedrun time being incorrectly calculated.
  

[h2]Controller[/h2]

• Fixed doubled cursor movement inputs on in-game menus such as computer hacks and the briefing lobby.
  
• Fixed extra inputs being generated when switching action set. This was causing the Override command to close and re-open the hack.
  
• Fixed an issue where after starting the game with Steam in Big Picture mode or using the controller, selecting a marine with the mouse would always select Sarge.
  
• Added convars rd_input_controller_mode_mouse and rd_input_controller_mode_keyboard to lock the input mode to not-controller (0) or controller (1).
  

[h2]Menus[/h2]

• Fixed non-English letters not being enterable into the lobby name field.
  
• Fixed 7.1 surround sound missing from 2010 audio settings menu.
  
• Fixed incorrect name for Order Specific Marine in the 2010 keyboard settings menu.
  
• Fixed download campaign button being obscured by the filters button.
  
• Fixed memory leak related to player avatars. This could sometimes lead to a "CUtlRBTree overflow" crash.
  

[h2]Infection Deathmatch Challenge[/h2]

• Reduced the amount of bonus maximum health that comes with Last Stand.
  
• Reduced the DPS of the chainsaw when using Last Stand.
  
• Slightly increased the DPS of the chainsaw when not using Last Stand.
  
• Freeze Grenades can no longer be used. (They were already unselectable.)
  
• Significantly increased Trip Mine damage against zombies.
  
• Significantly increased Gas Grenade damage against zombies.
  
• Significantly increased Incendiary Mine damage against zombies.
  
• Electro-stunned zombies now take double damage.
  
• Medic zombies now begin regenerating health sooner after taking damage.
  
• Fixed players falling through terrain when turning into a zombie.
  
• Updated custom edits for dm_deima.
  
• Added Classic variant:
  • Last Stand mode is disabled.
    
  • Prime Zombies no longer have shields.
• Improved bot marine pathfinding across all deathmatch game modes.
  
• Fixed sometimes seeing glows for weapons or ammo that have despawned.
  

[h2]Scripting[/h2]

• Added a new method to rd_hud_vscript: PaintPolygon(vertices, red, green, blue, alpha, texture). vertices is an array of tables, each containing x, y, s, and t coordinates. There must be at least three vertices and they should form a convex shape in clockwise order. x and y are screen coordinates. s and t are texture coordinates, from 0 to 1.
  

• Spectators will now see the full length laser pointer for the marine they are spectating.
  
• Using the healing ability on a medic weapon now dims the laser pointer in the same way that firing any other gun does.
  
• Lobbies with no ping information now sort to the bottom of the list by ping instead of the top.
  
• Fixed the Create Lobby screen not loading the saved lobby name from the previous lobby you created.
  
• Fixed reservations not being properly cleaned up when a player who played a marine in the previous mission fully connects and automatically selects their marines.
  
• Fixed sg-servers #2 not appearing as a ranked server (this fix went out as a hotfix yesterday).
  
• Custom main menu layouts can now use the commands for the top bar.
  
• Fixed a crash related to Steam avatar image handling in some custom layouts.
• Updated the Infection deathmatch challenge:
  • Attempt to fix a bug that sometimes instantly regenerates all players' health to maximum when another dies.
    
  • Last Stand users now gain bonus maximum health that scales with the number of zombies left.
    
  • Fixed a bug that sometimes resets zombie grenades to zero charges when a player dies.