Editing EDF sound reference (section)

==Ambience==
'''Ambience''' sections allow the user to define the behavior of ambient sound spots, which can be placed on maps using DoomEd numbers 14001 through 14065. The first 64 of these objects automatically use the ambience sections with numeric indexes 1 through 64. Object 14065 accepts the index number in its first argument field, which may be specified either through the use of ExtraData via the Hexen map format or via the upcoming UDMF format.

===Syntax===
 ambience
 {
   sound       = <sound mnemonic>
   index       = <number>
   volume      = <number>
   attenuation = <attenuation type>
   type        = <ambience behavior type>
   period      = <number>
   minperiod   = <number>
   maxperiod   = <number>
 }

===Usage===
*'''sound'''
:Default = "none"
:This field specifies the sound to be played by an ambience object using this definition. If the value provided to this field is invalid, no sound will be played. 
*'''index'''
:Default = 0
:Defines the index of this ambience definition. This may be an integer of any value zero or greater, although only the first 256 ambience definitions are usable via the Hexen map format. When an ambience definition has the same index as a previously defined ambience definition, it will overwrite that previous definition. Note that if a thing placed on a map references an invalid ambience sequence, that object will do nothing. 
*'''volume'''
:Default = 127
:The relative volume of this ambient sound, ranging from 0 to 127. This is multiplied by the user's volume setting so that the true range of volume is from 0 to the user's setting. For all attenuation types except "none", the volume is additionally decreased by the user's distance from the ambience object. 
*'''attenuation'''
:Default = "normal"
:This field defines the attenuation behavior of the ambience object. Attenuation is how the sound changes with distance between the listener and the ambience object. The following values are available for this field: 
:*normal -- Use the close_dist and clipping_dist fields defined in the sound definition.
:*idle   -- Use DOOM's normal default sound attenuation behavior.
:*static -- Fades quickly (inaudible from 512 units).
:*none   -- Plays at this ambience definition's volume level regardless of distance.
    
*'''type'''
:Default = "continuous"
:This field defines the repetition behavior of this ambience definition. The following values are available for this field: 
:*continuous -- loops the sound seamlessly
:*periodic   -- restarts the sound every "period" number of gametics
:*random     -- restarts the sound after a randomized wait period determined by the minperiod and maxperiod fields
    
*'''period'''
:Default = 35
:For periodic ambience definitions, this field defines how frequently the sound is restarted in gametics (1/35 of a second). 
*'''minperiod'''
:Default = 35
:For random ambience definitions, this field defines the shortest wait period before the sound will be restarted. 
*'''maxperiod'''
:Default = 35
:For random ambience definitions, this field defines the longest wait period before the sound will be restarted. The ambience object will wait a period of time somewhere between minperiod and maxperiod gametics, inclusive. For proper behavior, maxperiod should be a number greater than minperiod.
===Example===
 ambience
 {
   index       = 0
   sound       = ht_waterfl
   type        = continuous
   volume      = 127
   attenuation = static
 }
 
 ambience
 {
   index       = 1
   sound       = ht_bstsit
   type        = periodic
   volume      = 64
   attenuation = none
   period      = 70
 }
 
 ambience
 {
   index       = 2
   sound       = ht_bstatk
   type        = random
   volume      = 127
   attenuation = idle
   minperiod   = 35
   maxperiod   = 105
 }