itype (optional, default=0) -- determine the waveform of the oscillator. Default is 0.
itype = 0 - sine
itype = 1 - triangles
itype = 2 - square (bipolar)
itype = 3 - square (unipolar)
itype = 4 - saw-tooth
itype = 5 - saw-tooth(down)
The sine wave is implemented as a 4096 table and linear interpolation. The others are calculated.
Here is an example of the lfo opcode. It uses the files lfo.orc and lfo.sco.
Example 1. Example of the lfo opcode.
/* lfo.orc */
; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1
; Instrument #1.
instr 1
kamp = 10
kcps = 5
itype = 4
k1 lfo kamp, kcps, itype
ar oscil p4, p5+k1, 1
out ar
endin
/* lfo.orc */
/* lfo.sco */
; Table #1: an ordinary sine wave.
f 1 0 32768 10 1
; p4 = amplitude of the output signal.
; p5 = frequency (in cycles per second) of the output signal.
; Play Instrument #1 for two seconds.
i 1 0 2 10000 220
e
/* lfo.sco */