ADSREnvelopGenerator

ADSR Envelop generator struct.

Uses floating-point arithmetics, since most targets will use that. Shaping is done through the shpF() and shp() functions. A 0.5 value should return a mostly linear output, and a 0.25 an "audio-grade logarithmic" for volume, but since the calculation is optimized for speed rather than accuracy, there will be imperfections.

Members

Enums

Stage enum Stage: Indicates the current stage of the envelop.

Functions

advance double advance(): Advances the main counter by one amount.
isRunning bool isRunning(): Returns true if the envelop generator is running
keyOff void keyOff(): Sets the key position to off.
keyOn void keyOn(): Sets the key position to on.
keyOnNoReset void keyOnNoReset(): Sets the key position to on (no reset of counter).
keypos bool keypos(): Returns true if key is on
output double output(): Returns the current output as a floating-point value, between 0.0 and 1.0
position ubyte position(): Returns the current stage
shp double shp(double g): Changes the shape of the output using a fast and very crude power of function. Output is returned as a floating-point value between 0.0 and 1.0

Static variables

maxOutput double maxOutput;: The maximum possible output of the envelop generator
minOutput double minOutput;: The minimum possible output of the envelop generator.

Variables

_isRunning bool _isRunning;: If set, then the envelop is running
_keyState bool _keyState;: If key is on, then it's set to true
attackRate double attackRate;: Sets how long the attack phase will last (less = longer)
counter double counter;: The current position of the counter + unshaped output
currStage ubyte currStage;: The current stage of the envelop generator
decayRate double decayRate;: Sets how long the decay phase will last (less = longer)
isPercussive bool isPercussive;: If true, then the sustain stage is skipped
releaseRate double releaseRate;: Sets how long the release phase will last (less = longer)
sustainControl double sustainControl;: Controls how the sustain level will change (between -1.0 and 1.0)
sustainLevel double sustainLevel;: Sets the level of sustain.