Design philosophies and guidelines regarding placing of environmental sounds
By: Simon Viklund
Published :09 July 2006

  • Birds should only be placed in leaf trees (that is, not in palm trees) - this is because the birds are never seen. The foliage of a leaf tree would better �€œhide�€� a bird, and then the Player isn't as annoyed by the fact that he can't see the birds.
  • Not more than one bird per tree - but do not put a bird in every tree. I have placed about 80-90 bird sound sources on each map - use this number as a ruler. Too many sound sources will flood the audio atmosphere, and a sound card can't handle so many sounds at once anyway, so placing too many sound sources is just working in vain.
  • Crickets should be placed wherever there are birds - but not below the same trees that have birds in them. Place the crickets on lawns (near a brushed� 3d grass sprite) or below palm trees. I have put about 120 of cricket sound sources on each map - use this number as a ruler.
  • Frogs should only be placed near sewer entrances - where you would expect to hear frogs, but not see them. Do not place frogs where the Player will expect to see them, e.g. by the edge of a pond where he can walk close by.
  • Avoid placing any animal sound near a blown up building, helicopter pad or other location where something noisy has happened/happens frequently that would scare away the animals and insects. These areas should really come across as "dead"�, catering for a dynamic soundscape. Have some thought behind the placing of sound.
  • Factory sounds are placed in all factory buildings that have smoke coming out of them. Try to put the factory sound in the middle of the building's 3d model, so that the Player can't walk around the building and hear the noise inside play louder at any point.
  • Only place radio sounds in a maximum of two buildings per map - and make sure they're far apart. If it is an industrial map, do not place the radio in a building that already has a sound (ie, a factory with smoke coming out of it), but try to place the radio where there are not many environmental sounds in the vicinity. Always spread out sounds, use few sound sources economically rather than lavish.
  • Every once in a while, fly high above the map you're working on, and try to spot the areas which lack sounds. Use your imagination and put more sounds here - maybe there are not trees there, but you can put a bird on top of a building instead. The Player should't be able to walk anywhere where there are no environmental sounds.
  • If many sounds are to be placed in the same area - e.g. birds in a grove of trees - try to spread the birds and not put them in a straight "line"�. Since you know the maps and the missions, imagine the Player walking through the area and place the sound sources so that he is surrounded by the sounds.
  • Place sounds even in the buildings and trees, etc, that are outside the area in which the Player is allowed to move. It is important that the Player can hear sounds coming from outside the mission map - giving the feeling of there being a world outside - otherwise the world seems dead, fake, a simple backdrop.
  • Hot tip: Name all sound sources! All crickets should be named "cricket1", "cricket2" etc. This makes it possible to easily see in the world.xml file how many of each sound have been placed in the map. It also makes it a lot easier to troubleshoot if you find e.g. a factory that plays the sound of a frog, or similar problems.
I hope that helps.