• Changed the go-to-mod buttons in the manage and update tabs of the Mods GUI to switch to the install tab if needed. more
  
• Fixed that it was possible to open the command console while inside the technology GUI. more
  
• Fixed that it was not possible to build ghosts in normally visible area which is in fog of war in map view. more
  
• Fixed a crash when removing modded recipes while hand-crafting those recipes. more
  
• Fixed that nested CustomGuiStyle changes didn't work correctly. more
  
• Fixed that inserter would sometimes put items on the wrong side of the belt.
  

• Added only_in_alt_mode to LuaRendering draw functions.
  
• Changed LuaEntity::copy_settings() to also copy settings from ghosts.
  

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.

Read this post on our website

A few days ago I was investigating a rather minor bug report related to "Rotational Asymmetry in Belt/Inserter interactions" (aka Inserter was not behaving identically when rotated). This was a classic case of floating point equality comparison.

https://cdn.factorio.com/assets/img/blog/fff-297-inserters.gif

The Inserter would move it's arm and then it would pick up the item if the current arm orientation is equal to the desired arm orientation. Because of some chain of calculations related to rotation, some precision was lost and the equality check would fail for 1 tick, delaying the item pickup for 1 tick in some Inserter rotations. So I fixed that by finishing the inserter movement if it's close enough. Now the inserters should be a tiny bit faster in some rotations, plus all rotations should again be symmetrical and identical.

While analyzing the code and Inserter behavior for that bug, I also noticed that inserters with stack bonus would do nothing for 1 tick after picking up an item from a belt. I changed it so inserters will start moving to a new target immediately after they pick up something. This also sped up the Stack Inserter by a tiny bit.

Both the speedups were enough to fix another bug that was often regarded by the other devs as "not a bug": A Stack Inserter was not fast enough to pick up all the items placed on a belt by another Stack Inserter. Furthermore, because of different timings, the amount of items a Stack Inserter would pick up would depend on how far that Stack Inserter was from the item source:

https://cdn.factorio.com/assets/img/blog/fff-297-stack-inserters.webm

We released the change on Thursday. Something strange was quickly discovered after release...

https://cdn.factorio.com/assets/img/blog/fff-297-inserter-bug.webm

From Nefrums speedrun stream.

As someone from Twitch chat noted "Inserters are so fast now, they even don't care about the side of belt". Remember that I fixed the rotation problem by finishing the Inserter movement if it's close enough. Well, what ended up happening was what now the Inserter would stop 0.0001 degrees short of perfectly vertical. That was of course closer to the other belt lane so the item would be dropped there. Previously it was always dropped perfectly vertical, and the lane decision algorithm would choose the right lane. The fix was easy and it's probably released by the time you are reading this.

So with everything fixed, inserters are now more consistent, predictable and intuitive, things that I think are important for a precise game like Factorio. Some situation might end up being slightly slower or will consume a bit more electricity, but generally inserters are now faster.

In FFF-179 we presented new resource graphics for Factorio 0.15. When the resource graphics were finished, we tried to cut pieces from them and compose these into new item icons - but the results were not better than what we already had and we needed to do many more things for 0.15, so we kept the resource icons as they were for the time being.



Recently we have started work on higher resolution for icons, and the resource icons are one of the first families to get a revisit.

As mentioned in FFF-179, to save time when creating the resource graphics we used various randomization methods to get a new batch of re-randomized resource pieces easily. This method has one big drawback for icons - it’s very hard to preview and control in Blender.



However the random generation allows us to generate many random pieces of resources very quickly...



...and combine them in Photoshop into icons with perfect control over every pixel.



However when we put these icons in the game, on belts they seem to suffer a lot from repetitiveness just like the older versions did.



There was one more thing regarding resource icons that we tried to do for 0.15 but did not have enough time for - resources would get randomized variations of icons when drawn on belts.

Rendering more variations and assembling new icons was relatively easy at this point, so we made some more versions.



With randomized variations the resources look much more natural and unrefined, which makes a lot of sense as The Factory has not processed them into perfect uniform products yet.

https://cdn.factorio.com/assets/img/blog/fff-297-animated.webm

The new icons are not ready just yet, but we hope to have them for the 0.17 stable.

As always, lets us know what you think on our forum.

• The resource frequency slider in the map generator settings has a smaller influence over the amount of ore in the starting area patches. more
  
• Inserters with stack bonus are now smarter when picking up items, and thus slightly faster. more
  

• Fixed that researching the appropriate technology would re-add shortcut buttons to the shortcut toolbar even if the player explicitly removed them earlier. more
  
• Fixed that some saves that contained multiple surfaces would cause the game to crash on load. more
  
• Fixed that auto-barreling opt-out didn't work if the fluid has icons defined. more
  
• Fixed that auto-barreling recipes would use the wrong fluid name if the fluid had a custom localised name defined. more
  
• Fixed that the entity damaged event original_damage value wouldn't be accurate if the entity had shields or resistances. more
  
• Fixed a performance problem related to the undo logic and large blueprints. more
  
• Fixed that trying to join Steam networking enabled games with Steam networking disabled didn't work correctly. more
  
• Fixed that trains built part of a blueprint was snapping to train stop which could prevent some specific blueprints from being built.
  
• Fixed smoke for generators without animation. more
  
• Fixed train circuit conditions not working properly sometimes when arriving at disabled station. more
  
• Fixed transparency of tables. more
  
• Fixed reintroduction of blueprint train building problems. more
  
• Fixed that the game could freeze on exit on Linux after clicking a link. more
  
• Fixed statistics windows showing strange totals in some situations. more
  
• Fixed statistics windows not showing the first few values (e.g. when an items is produced for the first time). more
  
• Fixed that belt immunity equipment would drain energy in armor when not equipped. more
  
• Using the NO_SCHEDULE train state more consistently (for train in automatic mode with empty schedule. more
  
• Fixed inserters behaving differently when rotated. more
  
• Fixed that the control key would be ignored by Factorio on Linux if the "Press Ctrl to highlight the pointer" (or equivalent) option was enabled. more
  
• Fixed that cloning tiles in the map editor wouldn't always clone transitions correctly. more
  
• Fixed that the supply mission finished game GUI was too small. more
  

• Added optional assembling machine gui_title_key property.
  
• Changed belt immunity equipment to consume energy through "energy_consumption" instead of "energy_source.drain".
  

• Added LuaGuiElement::vertical_centering read/write.
  
• Added LuaEntity::auto_launch read/write.
  
• Added LuaTransportLine::line_equals().
  

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.

• The argument to --generate-map-preview is treated as a directory only if it ends with a '/' or '\'.
  
• Car/tank color keeps the color of the last user.

• Fixed that the technology GUI could freeze on certain technologies. more
  
• Fixed a crash when trying to build train ghosts not on rails. more
  
• Fixed a crash related to changing the logistic mode on an infinity-chest type entity through mods. more
  
• Fixed low readability tag color highlighting in textboxes. more
  
• Fixed Korean IME still did not work (Windows only). more
  
• Fixed statistics graphs X axis labels showing wrong values for 250h and 1000h time frames. more
  
• Fixed that the wrong entry could be highlighted in the electric network graph. more
  
• Fixed that picking up an item from quickbar wouldn't reserve the slot with an inventory hand when the inventory was full. more
  
• Fixed robot energy consumption when using very high speed bonuses. more
  
• Fixed a false-positive changed message in the mods GUI under specific situations. more
  
• Fixed icons inside blueprint book items not being scaled properly.
  
• Fixed that delimit-procedure noise expressions at the root of an expression tree would crash the compiler.

• Added util.combine_icons(icons1, icons2, inputs) function to aid in combining icons tables.
  
• Changed the auto_barrel recipe icon generation to account for fluids with an icon_size not set to 32, or fluids with an icons table. more

• Added LuaNamedNoiseExpression and LuaGameScript::named_noise_expressions read.
  
• Added LuaEntity::tree_stage_index read/write.
  
• Added LuaEntity::tree_stage_index_max and tree_color_index_max read.
  
• Added "player_index" to the on_rocket_launch_ordered and on_rocket_launched events.

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.

This really is a tiny feature, the car and tank will now save the color of the passengers when they exit the vehicle.



So now you won't forget which vehicle you were driving, and can warn everyone else on the server: "Pink tank is mine".

As uninteresting as it is; most bugs are boring and typically involve missing code. Someone forgot to implement part of a new feature, forgot that some situation could happen, forgot to check for null. Rarely interesting things show up where everything is working but not how we want it to.

Recently we had a bug report where a modded game would freeze for a minute for seemingly no reason and then continue like nothing went wrong. It being a heavily modded game my first reaction was to blame it on the mods doing something in a very unoptimized way. But I had to test it to figure out which mod was causing the problem. After reproducing it... I was reminded (again) that it's (almost) never what you think it is.

When a train is driven by a player the game has no idea what direction the player will drive (straight, left, or right). So, as the train is moving the game goes over the potential rails in front of the train and asks every gate it finds to open in case the train ends up driving over them. This logic was very simple: get the rail distance it would take the train to stop at its current speed and "walk" down the rails until it exceeded that distance. As it walked, tell any gates on any of those rails to open.

That logic is "correct" in that it does what it was supposed to do: open any gates that the train could drive over. What it wasn't accounting for was a rail system where everything looped back onto itself 5-10 times per junction.The time complexity for the algorithm it was using was O(N^2). That's "fine" when N is small. However, in this save file, with this rail network, and with these modded trains (with 2,500% speed bonus from modded fuel no less) it meant N ended up somewhere around 75,865. That - as it turns out - was slow.



Interestingly even though the algorithm was recursive it didn't stack overflow. The old algorithm was executing the "open gates on this rail" 5,755,573,057 times. Many of those requests to open gates where duplicates but the algorithm didn't care. In total it took 57 seconds for it to run all of the logic - still incredibly fast for what it was doing (1.6 million rails per game tick).

After some thinking about it; I was able to re-implement the algorithm in worse-case O(N) time which ended up executing the "open gates on this rail" logic 42,913 times and took 0.009 seconds.

I love this phrase. It's both correct and incorrect at the same time. I put it right next to "Crashing from an exception? Just try-catch". It's such an easy trap to fall into: fixing a symptom instead of the cause.

Earlier this week we got a bug report about the game freezing, consuming all of the available RAM, and then crashing when it ran out of RAM. It was again a modded save file so my first instinct was to blame it on a mod. Again, I had to test it. And again... it's never what you think it is.

The crash was correct: it was running out of RAM and when that happens the game crashes and exits. But why?

• The game failed to allocate memory when it tried to create a furnace smoke
• Because it was trying to make 4'294'967'000~ (4 billion) smokes
• Because a small negative signed integer was being converted to unsigned

Clearly the game wasn't supposed to be making 4 billion smokes. So, seeing the problem my first fix was "Casting a small negative signed integer to unsigned makes it 4 billion? If it's negative, I'll just return 0 since a negative amount of smoke makes no sense". I was about to commit this fix when the smarter part of my brain said "that makes no sense, why would this code ever say to make a negative amount of smoke?" So I kept going ... why?

• ... Because the logic to make those signed integers was "(cycle progress ...) - (last cycle progress ...)" (cycle was < last cycle ... that should never be possible)
• Because the furnace burner had made a negative amount of progress in burning the fuel (negative progress should not be possible)
• Because the "remaining amount of fuel from this item to burn" was negative (negative fuel values are invalid and the game won't even reach the main menu if some mod tries to set one)
• Because the mod API didn't prevent mods from doing: entity.burner.remaining_burning_fuel = -1 AND the game didn't properly clear "remaining amount of fuel from this item to burn" when the item being burnt was removed due to mod migration/removal.

So, I still repeat the phrase: "Crashing on dereferencing null? Just add a null check!" as a reminder to myself and others to always look deeper into why and never stop at the basic symptom of a problem.

As always, let us know what you think on our forum.

• Tweaked default graphics settings. The game should choose better default graphics settings for computers with integrated GPUs or less than 6 GB of RAM.
  

• Fixed that GUI element size wasn't updated in inactive tabs when ui scaled changed. more
  
• Fixed "Confirm Message" conflicting with some key-bindings. "Confirm Message" can no longer be bound to mouse input. more
  
• Fixed possible crash when rendering GUI element with dynamically loaded sprite. more
  
• Fixed recipe window showing wrong item count or not enough ingredients in some situations. more
  
• Fixed a crash when deleting the force of a car with an active logistic network through vehicle equipment grid. more
  
• Mod names are no longer allowed to contain rich text. more
  
• Fixed IME (Input Method Editors) did not work (Windows only). more
  
• Fixed placement of oil and uranium patches back to that of 0.17.40. more
  
• Fixed that roboports with a request_to_open_door_timeout of 0 wouldn't work correctly. more
  
• Fixed that products wouldn't allow amount_min of 0 for items. more
  
• Fixed that migrated/removed fuel items could leave the game in an invalid state. more
  
• Fixed a crash when building combat robots after resetting the achievements in-game. more
  
• Fixed that assembler ghosts would carry over the unresearched blueprint bug from 0.17.38. more
  
• Fixed crash related to clearing a blueprint book from the cursor. more
  
• Fixed that the rotation of blueprint was not saved to the blueprint library in some situations.
  
• Fixed bad icon in pollution statistics. more
  
• Fixed hand icon not disappearing when you grab a blueprint from chat. more
  
• Fixed that reviving modded tile ghost entities could destroy other entities in some situations. more
  
• Fixed car tooltip showing it's moving when it's not actually moving.
  
• Fixed car rotating in place when the speed is very low. more
  
• Fixed that fluid wagons could not carry fluids with sub-zero temperatures. more
  
• Fixed that rolling stock "must be build on rails" error was not using the name of the rolling stock. more
  
• Possibly handled fullscreen window being moved to screen of different size on Windows. more
  
• Fixed a crash when using table_size() without any argument. more
  
• Fixed players getting a new player character when they connect after disconnecting, connecting and disconnecting again from a paused game. more
  

• Added map-gen-seed-max command line parameter.
  
• Added generate-map-preview-random command line parameter.
  
• Changed generate-map-preview command line parameter to need PATH instead of PNGFILE, the file name is now always the seed.
  
• Made "apply_recipe_tint" be applied also to "light" working visualization effects of crafting machines.
  
• Added "use_fuel_glow_color" property to reactor prototype.
  

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.

Read this post on our website

Hello,
the bugfixing period boringly continues, we got down to 159 active bug reports, so in few weeks we should be finally down with this burden. But at least the graphics department has something new to show:

After some time working on the redesign of the chemical plant, we can finally show the results:



In the old version, we had the problem of not being very clear when the chemical plant was working or not. So apart from the style modernisation and high resolution, this redesign was aimed for solving this readability issue. As an addition, we tried also to be very clear at the time of viewing what kind of chemical recipe the plant is processing.

Finally we came with the solution of adding a big window - pipe style - showing the moving liquids inside with the tinted color, and also adding a chimney releasing smoke when the plant is on.

As you can see in the animation above, the smoke is also taking the tinted color of the processed chemical, so it should be crystal clear what it’s going on now with this entity. This tinted smoke is very experimental, and we need to make more testing before releasing it, the point is to avoid a too colorful pollution, but in terms of concept I find it 'very chemical' having colored smoke, which could fit perfectly with the subject.

Here you can see the four rotations:



Factorio wouldn’t be Factorio if the things would be easy as "rotate the model in 3D and done". Due to readability requirements, camera perspective, and interaction with any other entity in the game, we have to recompose the entity for every rotation. That’s why even rotating the entity 90 degrees the window remains at the front, and the chimney at the back.
Basically every rotation is like a new entity that tries to look like its other rotations, but somehow rotated (!?).

We truly believe that this new design is going to be a good improvement for the game. Slowly but steady, Factorio is getting to its 1.0 release.

As always, let us know what you think on our forum.

• Fixed that some noise expression types used by some mods (literal map positions, offset-points, and distance-from-nearest-point) were unimplemented.
  
• Fixed that blueprint rotation was not saved for blueprint books in the blueprint library. more
  
• Fixed that the focus-search shortcut could be used to bring up the search field when it was disabled. more
  
• Fixed that game.reload_script() could break LuaRecipe/LuaPrototype references.
  
• Fixed a PvP script error on configuration changed. more

• Added LuaEntityPrototype::item_slot_count read.
  
• Added LuaEntity::get_stopped_train().
  
• Added "surface_index" to the on_post_entity_died event.

You can get experimental releases by selecting the '0.17.x' beta branch under Factorio's properties in Steam.

• Improved efficiency of noise program compilation and quality of error messages.
  

• Fixed a crash that would sometimes happen after deleting a blueprint from the library. more
  
• Fixed crash related to train schedule containing only temporary stations. more
  
• Fixed GUI inspector vertical align value inconsistency (middle instead of center). more
  
• Fixed LuaInventory::sort_and_merge when used on cargo wagons with inventory limits set. more
  
• Fixed that distractor robots would show in the bonus GUI under the follower robots section. more
  
• Fixed that reading invalid chain signals wouldn't work correctly. more
  
• Fixed yet another ghost connection error related to consistency checks. more
  
• Fixed some cases of multi-layered icons not being scaled correctly. more
  
• Fixed power switch connection consistency problem. more
  
• Fixed "Confirm Message" key-binding not working when bound to some mouse buttons. more
  
• Fixed backwards/forwards max speed fuel modifier related to two-headed trains. more
  
• Fixed interactions of assemblers and underground pipe connections blocked by induced fluid mixing. more
  
• Fixed setting entity ghosts to minable=false didn't work. more
  
• Fixed that the statistics GUI would show count values < 0.5 as "no count". more
  
• Fixed a performance problem with high speed idling trains on circular rail networks. more
  
• Fixed signal placement visualisation for special cases related to straight diagonal rail. more
  
• Fixed that items supposed to be removed on clearing cursor (copy, cut, paste, blueprints from blueprint library etc.) were put into character corpse. more
  
• Fixed uranium cannon shells shooting backwards when aimed closed to the tank.more
  
• Fixed Programmable Speaker alert textbox not losing focus when pressing ENTER. more
  
• Fixed desync caused by setting font colors on buttons. more
  

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.

• Fixed that hand crafting wouldn't respect the hide_from_flow_statistics property. more
  
• Fixed that modded GUI tables did not display borders that were set in their style.
  
• Fixed the game would fail on startup if control settings were reset during migration of 0.16 config file. more
  
• Fixed that train stop "must be build next to rails" error was not using the name of the train stop. more
  
• Fixed that beam damage interval was sometimes not respected properly.
  
• Fixed that beams would be immediately created and destroyed when standing very close to max range.
  
• Fixed that beams would not show any animation if the target was killed in one hit. more
  
• Fixed that laser beams would always aim at player character's feet.
  
• Fixed entity hit_visualization_box not working properly.
  
• Fixed running out of memory during sprite loading was not handled gracefully. more
  
• Fixed a map corruption problem when creating games from scenarios that used difficulties per-entity. more
  
• Fixed that some Lua errors wouldn't show proper lua stack traces. more
  
• Fixed a crash related to reading pollution statistic values through Lua. more
  
• Fixed a crash resulting from building a blueprint of an assembler with a fluid recipe that is not researched yet. more
  
• Fixed that temporary blueprints (e.g. from the copy tool) would sometimes go to inventory instead of being destroyed. more
  
• Added fluid mixing check to infinity pipe. more
  
• Fixed that you could build rail ghosts in the basic rail tutorial. more
  
• Fixed special case of dragging station/condition order in the train configure GUI. more
  
• Fixed tightspot script error starting the round with flying text on the map. more
  

• Changed the mods GUI so it lists mod settings by mod alphabetically using natural ordering.
  

You can get experimental releases by selecting the 'experimental' beta branch under Factorio's properties in Steam.