How to create FPS using audio not graphics

good morning so my name is antoine pastor and i'm going to talk to you about games for your ears or how to make a new game so i'm working in a company called something else we're based in london and we make a lot of different things from tv to radio shows and uh of course games and over the last five years we've released four audio games including papa sangre and audio defense which i'm going to talk about today so in case you don't know what a node game looks like here is a screenshot of papa sangre 2 so that's level 7 when you're stuck in a submarine and you can hear radioactive leaks all around you and this is a screenshot of level eight where you're in the zoo surrounded by

weird animals and you can see that there's not much difference between these two screenshots because like all the difference happens in your headphones and you can hear 3d sounds in your earphones and basically your device is just a controller and you don't even need to look at it but as i've told you already i'm mainly going to talk about your defense today and to explain it like more briefly i'm going to show you the trailer because that's probably the best thing to show so here we go here comes the new generation of zombie shooter the lowest resolution zombies you've ever seen and that you aren't gonna see because this game has no graphics put your headphones on there are zombies you can hear them but you can't see them

turn carefully until the zombie sound is in front of you come on shoot him what are you waiting for yeah you're surrounded yeah choose your weapons so how does this work uh because we've got nothing on screen you need a very accurate way to represent the sound around you and to do this we're using the papa engine which is an engine we've made in-house and we are distributing and it lets us recreate a 3d sound environment around the player

and it's basically so accurate that when you close your eyes you can say exactly where a sound is coming from and it's not only like oh it's coming from my right or my left you can see it's coming exactly from there for example so to do this we're using a technology called hrtf and it's basically a function that describes how a sound is coming to your ear so in that case you can see that the sound the distance between the sound and your left ear is a bit longer than the distance between the sound and your right ear and that's basically what that function describes and we've got 188 of these functions to describe the sounds all around the player and whenever we need to like specialize the sound in the game we just need to pick the right function in the database so for example when we need

to specialize a zombie at this position we will take the hrtf function for angle 345 and apply it to the sound and that's how we turn a flat mono sound into a 3d sound but technology isn't everything and what really matters when you play a game is the gameplay and for our first three games we've relied mainly on narrative so in all of these games you had a narrator that would help you go through the levels and for example in papa sangre 2 it was shown being the actor from game of thrones and he would explain to you what the level is like and what you needed to do so the pace of the game would be quite slow because you really needed like to understand what you have to do

but in the other hand that would let us create some very rich environment so i've talked to you about like the submarine but we also have a house on fire or things like that and in these environments what you needed to do was to take a few steps listen to your environment like take a clue of what your next next objective was so for example try to listen for the door and the enemies and try to get the patrol of the enemy and then take a few steps to the door then listen again and move again so the pace of the game was quite slow and when we've built audio defense we've tried to make a completely different game so if we take a look at the game design we will see that we've tried to completely change these four key points so in papa song i told you it was really

important to listen then move but in audio defense we've chosen to completely get rid of the ability for the player to move because we figured out that it was actually really hard for the player to figure out where they are in a room but they could very precisely say where the sound were around them so we've chosen to like use that at the main game mechanic and as a consequence the game is really easy to play and really anyone can just pick a device and play and also we wanted to make a game that was like much more of an arcade game and fun to play so we got rid of the slow pace and instead of that we've packed a lot of action into audio defense and that's why we pretty much got rid of all the narrative to focus really on the shooting and we also got rid of creating very rich

environments and instead of that we focused a lot of uh all the effort of the sound design in creating a very broad range of enemies so we've got like 15 different enemies with very specific behaviors and way to attack the player and one important thing when building audio game is the interface or i should say the lack of interface so if you look at a normal zombie shooter on the app store like dead trigger 2 you can see that you've got a lot of stuff going on on the screen so you've got like five different buttons a mini map a live bar your score the current weapons how many bullets you've got left all that sort of stuff in all your defense the only thing you see when you play is this and that's it so you've got no feedback at all on where your enemies are because that all happens through 3d sounds in

your headphones and the only thing you see is the current gun you've got equipped and those redline that are some feedback about like the way you're looking at so when you move you will see these red lines moving but they don't give you any feedback on where your enemies are and then you just swipe up to change weapons swipe down to reload and shake your device to attack with your melee weapon and that's it and it's actually so easy to play that you can play without looking at the screen and when we demo the game in some events we like to take that big cardboard box with us and it's like full of foam to isolate you from the sound of the outside and actually when you put it you can't see anything you can't even see the screen but people can still play and it's actually amazing to see that people like discover that they can play without looking at the screen and they usually really enjoy it because it's a brand new

experience to them but because we have no interface you get that the sound design is very very important and in a zombie game uh well the most important thing is the zombie sound of course so for each enemy we've got a large panel of sounds so for example when it appears it will make a specific sound like this one can you put the volume up please and then when it moves towards you you will hear it moving so you hear the footsteps and the moaning and then when it's really close you can hear it being more aggressive like that if you don't kill it when it's being aggressive of course it will attack you and then it's game over for you and as i've told you already we don't

have a live bar in our game so we had to find a way to like represent danger to the player and what we've chosen to use is your heartbeat so when you when you hear your heart beating it means that a zombie is really close to you and that you've got to get rid of it like that so a zombie is approaching and you start hearing your heartbeat and because you didn't kill it well you're dead and then on the game of the screen you hear like that sort of hospital sound and you've got an opportunity to try again and because it's a zombie shooter weapons are very very important and we've got loads of different weapons in that game and they're giving you feedback about like how well you're doing so if you're shooting you will hear the sound of your gun but if you're hearing and hitting your target you will hear a blood splatter so that's a very subtle

difference like that and if you're shooting your enemy and killing it the blonde splatter will sound much more gore like this and on top of that you will also hear the moaning of the zombie you're shooting because there are different kind of zombies and you want to know which one you you've been shooting at so you will hear something like that and if you've been lucky enough to kill it you will hear the zombie falling on the floor like this and that's the sign that you can stop shooting a bit zombie and like focus on another zombie somewhere else and because we've chosen not to show on the screen how many bullets you've got left we had to come up with another system so when you're shooting with your micro smg you will hear these but when you're almost running out of web of bullets the song will be slightly

different like that and that's actually the sign that you need to reload otherwise you're going to like run out of bullets and sound is your lie but sound can also be your enemy and not only because zombies have sounds but also because we love to throw stuff at players to challenge them so for example when you're fighting zombies there can be a jukebox that will appear in the arena for no reason and it will cover the sound of the zombies so you really want to shoot at that jukebox to get rid of it and be able to focus on the zombies and you can also have a thunderstorm and basically when you hear that sound it's the same it covers the sound of the zombie for a few seconds you can't really say where they are anymore but my favorite one is when an explosion happens really close to you you got that very annoying high-pitched sound

and on top of that like all the sound of the zombies get really really reverb making it much much harder to to guess where they are so that's it for the sound design and i'm now talking going to talk about the balance so in our previous game papa song ray we realized that a lot of players dropped after level five so if you look at the green bars that's how many players got through each level and you can see that not a lot of players made it to level 7 and that's a real shame because we've put a lot of effort in making level 6 to 18. that's where most of the action takes part like that summary in the burning house the zoo and the tutorial happened in much like emptier room so it's a real shame that people dropped the game before they got to experience

what we wanted them to experience so in audio defense uh we've made the tutorial level levels much shorter and much easier to play and you can see that much more players got to play our like levels 5 to 10 because that tutorial is really short and when it when they are done with the tutorial they got into the main game loop which is buying weapons uh going into the arena getting some coins buying better weapons upgrading them and scoring better in the arena and for the first time in our games uh we've been able to make leaderboards so both on twitter and on the game center and as you can see if you look at our twitter feed some players are very very committed to the game

and at the bottom of the list you can see someone who has killed 281 zombies when my best score is probably something around 40 or something like that and another thing you can see on that picture is that a lot of our followers don't have a profile picture and that's because they are blind and they don't need a profile picture and blind players are a very very important part of our audience and we take a lot of care in making our game accessible so on this picture you can see two versions of the same screen so the one at the top is the normal version but if we detect that our user is blind and has turned the screen reader on then we create a brand new version of the screen it's actually the same game in the app store but it's just detecting

that the player has a screen reader and we're using normal ios stuff to display the screen in a much like blind flame friendly way and in the same way we've read on pretty much every screen of the game for blind players but if you're interested in like making game accessibles the next speak will talk like much better than i do about it so that's it for me thanks for your attention and if you have any question i'll be at the back