lincos — Linear to cosine interpolation
Plugin opcode in emugens.
Maps a linear range of values to a cosine (easy-in/easy-out) range of values. At present it supports only scalars, at i- and k-time (no arrays)
kx -- Input signal
ky0 -- Lower limit of output range
ky1 -- Higher limit of output range
kx0 -- Lower limit of input range (default = 0)
kx1 -- Higher limit of input range (default = 1)
dx = ((x-x0) / (x1-x0)) * PI + PI y = y0 + ((y1 - y0) * (1 + cos(dx)) / 2.0);
Here is an example of the lincos opcode. It uses the file lincos.csd.
Example 509. Example of the lincos opcode.
<CsoundSynthesizer> <CsOptions> </CsOptions> <CsInstruments> sr = 44100 ksmps = 128 nchnls = 2 0dbfs = 1.0 ; Example file for lincos.csd /* lincos similar to cosseg, but with an explicit input for time lincos can be used ease-in / out any linear ramp ky lincos kx, ky0, ky1, kx0=0, kx1=1 iy lincos ix, iy0, iy1, ix0=0, ix1=1 */ seed 0 instr 1 ; Map a value within the range 1-3 to the range 0-10. iy lincos 1.5, 0, 10, 1, 3 print iy kx line 1, p3, 3 ky lincos kx, 0, 10, 1, 3 printks "kx: %f ky: %f \n", 1/kr, kx, ky endin instr 2 ; lincos can be used to create amplitude or pitch envelopes ktrig init 0 krnd dust 1, 1 ktrig = lineto(tirghold(krnd & ~ktrig, 0.5), 1) kpitch = lincos:k(ktrig, 60, 61) a0 oscili 0.7, mtof(kpitch) kfade lincos linsegr(0, 1.5, 1, 1.5, 0), 0, 1 kcresc lincos ktrig, 0.25, 1 outch 1, a0 * interp(kfade * kcresc) endin </CsInstruments> <CsScore> i 1 0 0.2 i 2 0 20 </CsScore> </CsoundSynthesizer>