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Aviator on the BBC Micro

Sound: envelopeData

Name: envelopeData [Show more] Type: Variable Category: Sound Summary: Data for two sound envelopes
Context: See this variable in context in the source code References: This variable is used as follows: * DefineEnvelope calls envelopeData * MakeEngineSound calls envelopeData * MakeSoundEnvelope calls envelopeData

There are two sound envelopes defined in Aviator. * Envelope 1 defines the engine sound. The third, fourth and fifth values (envelopeData+2, envelopeData+3 and envelopeData+4) control the choppiness of the engine sound and get altered by the MakeEngineSound routine, depending on the thrust and airspeed. These values control the change of pitch per step in the three stages of the sound envelope, so higher values make the sound jump up and down more in terms of pitch, which makes the sound more choppy and less smooth. * Envelope 2 defines the sound of gunfire, both for our Spitfire and for the Theme aliens.
.envelopeData EQUB 1, 1, 50, -50, 50, 1, 2, 1, 0, 0, 0, 0, 0, 0 EQUB 2, 1, -5, 0, 0, 10, 0, 0, 120, -1, -24, -10, 120, 116