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Version4_16.Notes
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2002-02-17
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Release Notes for 4.16
======================
A great deal of internal reorganisation, and catching up on opcodes
and gens in use elsewhere. And of course the usual collection of bug
fixes and bug introductions.
Bug Fixes
---------
Bad characters in score introduced by the sorting process fixed.
Off-by-one error in score macros fixed
Bug fix in piped input and output; may improve things a little
Off-by-one error in reading input sounds with skipping
Writing EPS graphs was not correct for macintosh
IRCAM format should be OK again
Bug in schedule/turnoff fixed
Language Changes
----------------
Sound fonts are looked for in current directory sample director and
analysis directory.
Scores can now have an x opcode which skips the rest of the current
section.
Opcode Fixes
------------
Obscure bugs in jitter/jitters and jitter2 fixed
Minor bugs in pv on-the-fly
rezzy now not a disaster if rez is set to zero.
Similar in moogvf and svf (and code optimised)
A rounding error problem in k-rate linseg fixed
New Opcodes
-----------
cuserrnd --
urd -- (function)
octave, semitone, cent, db -- (functions)
grain2, grain3 -- New granular synthesis opcodes
rnd31 -- 31-bit bipolar random opcodes with controllable distribution
New Gens
--------
Gen24
Gen30 (Istvan Varga)
Gen31 (Istvan Varga)
Gen40
Gen41
Gen42
Other Changes:
-------------
Improved error messages when sfont fails
Improve phase calculation in oscbnk
musmon re-organised to allow for external use
Significant optimisations in deltap3 and vdelay3
resonz and resonr optimised
Known Bugs
==========
The following bugs are known but not yet fixed
2: ADSR can go wrong
6: PVOC can glitch (mail of Mon, 19 Jun 2000 00:45:23 +0200)
8. Spaces in arguments to opcodes can be ignored, giving oddities
9. Mismatched closing bracket can give crash (mail of Fri, 19 Oct 2001
19:00:56 +0100)
Windows GUI Changes
-------------------
Added DAC button
-----------------------------------------------------------------------
==John ff
2001 December 10
========================================================================
GEN30
=====
f # time size 30 src minh maxh [ref_sr]
GEN30 extracts a range of harmonic partials from an existing
waveform.
src - source ftable
minh - lowest harmonic number
maxh - highest harmonic number
ref_sr (optional) - maxh is scaled by (sr / ref_sr). The
default value of ref_sr is sr.
GEN31
=====
f # time size 31 src pna stra phsa pnb strb phsb ...
This routine is similar to GEN09, but allows mixing any
waveform specified in an existing table.
src - source table number
pna, pnb, ... - partial number, must be a positive integer
stra, strb, ... - amplitude scale
phsa, phsb, ... - start phase (0 to 1)
[Istvan Varga]
------------------------------------------------------------------------
ar grain2 kcps, kfmd, kgdur, iovrlp, kfn, iwfn[, irpow[, iseed[, imode]]]
ar grain3 kcps, kphs, kfmd, kpmd, kgdur, kdens, imaxovr, kfn, iwfn, \
kfrpow, kprpow[, iseed[, imode]]
INITIALIZATION
==============
iovrlp - (fixed) number of overlapping grains in grain2.
imaxovr - maximum number of overlapping grains in grain3. The number of
overlaps can be calculated by (kdens * kgdur); however, it can be
overestimated at no cost in rendering time, and a single overlap uses
(depending on system) 16 to 32 bytes of memory.
iwfn - function table containing window waveform (GEN20).
irpow - this value controls the distribution of grain frequency variation.
If irpow is positive, the random distribution (x is in the range -1 to 1) is
abs(x) ^ ((1 / irpow) - 1); for negative irpow values, it is
(1 - abs(x)) ^ ((-1 / irpow) - 1). Setting irpow to -1, 0, or 1 will result
in uniform distribution (this is also faster to calculate). The image
"grain2_rand.png" shows some examples for irpow.
The default value of irpow is 0.
iseed - seed value for random number generator (positive integer in the range
1 to 2147483646 (2^31 - 2)). Zero or negative value seeds from current time
(this is also the default).
imode - sum of the following values:
64: (grain3 only) synchronize start phase of grains to kcps.
32: (grain3 only) start all grains at integer sample location. This may be
faster in some cases, however it also makes the timing of grain envelopes
less accurate.
16: (grain3 only) do not render grains with start time less than zero (see
the image "grain3_1.png"; this option turns off grains marked with red
on the image).
8: interpolate window waveform (slower).
4: do not interpolate grain waveform (fast, but lower quality).
2: grain frequency is continuously modified by kcps and kfmd (by default,
each grain keeps the frequency it was launched with). This may be
slower at high control rates. In grain3 it also controls phase
modulation (kphs).
1: skip initialization.
The default value is 0.
PERFORMANCE
===========
ar - output signal.
kcps - grain frequency in Hz.
kphs - (grain3 only) grain phase.
kfmd - random variation (bipolar) in grain frequency in Hz.
kpmd - (grain3 only) random variation (bipolar) in start phase.
kgdur - grain duration in seconds.
kdens - (grain3 only) number of grains per second. In grain2, this is fixed to
(iovrlp / kgdur).
kfrpow - (grain3 only) distribution of random frequency variation (see irpow).
kprpow - (grain3 only) distribution of random phase variation (see irpow).
Setting kphs and kpmd to 0.5, and kprpow to 0 will emulate grain2.
kfn - function table containing grain waveform. Table number can be changed at
k-rate (this is useful to select from a set of band-limited tables generated
by GEN30, to avoid aliasing).
AUTHOR
======
Istvan Varga
2001
------------------------------------------------------------------------
ix rnd31 iscl, irpow[, iseed]
kx rnd31 kscl, krpow[, iseed]
ax rnd31 kscl, krpow[, iseed]
DESCRIPTION
===========
31-bit bipolar random opcodes with controllable distribution. These
units are portable, i.e. using the same seed value will generate the
same random sequence on all systems. The distribution of generated
random numbers can be varied at k-rate.
INITIALIZATION
==============
irpow - this value controls the distribution of random numbers.
If irpow is positive, the random distribution (x is in the range -1 to 1) is
abs(x) ^ ((1 / irpow) - 1); for negative irpow values, it is
(1 - abs(x)) ^ ((-1 / irpow) - 1). Setting irpow to -1, 0, or 1 will result
in uniform distribution (this is also faster to calculate). The image
"grain2_rand.png" shows some examples for irpow.
iseed - seed value for random number generator (positive integer in the range
1 to 2147483646 (2^31 - 2)). Zero or negative value seeds from current time
(this is also the default). Seeding from current time is guaranteed to
generate different random sequences, even if multiple random opcodes are
called in a very short time.
In the a- and k-rate version the seed is set at opcode initialization. With
i-rate output, if iseed is zero or negative, it will seed from current time
in the first call, and return the next value from the random sequence in
successive calls; positive seed values are set at all i-rate calls.
The seed is local for a- and k-rate, and global for i-rate units.
Notes:
- although seed values up to 2147483646 are allowed, it is recommended
to use smaller numbers (< 1000000) for portability, as large integers may
be rounded to a different value if 32-bit floats are used.
- i-rate rnd31 with a positive seed will always produce the same output
value (this is not a bug). To get different values, set seed to 0 in
successive calls, which will return the next value from the random sequence.
iscl - output scale. The generated random numbers are in the range -iscl to
iscl.
ix - i-rate output value.
PERFORMANCE
===========
krpow - same as irpow, but can be varied at k-rate.
kscl - same as iscl, but can be varied at k-rate.
kx - k-rate output value.
ax - a-rate output value.
EXAMPLES
========
; a-rate random numbers in the range -2 to 2 with triangle distribution,
; seed from current time
a1 rnd31 2, -0.5
; k-rate random numbers in the range -1 to 1 with uniform distribution,
; seed=10
k1 rnd31 1, 0, 10
; i-rate random numbers with linear distribution, seed=7
; (note that seed was used only in the first call)
i1 rnd31 1, 0.5, 7
i2 rnd31 1, 0.5
i3 rnd31 1, 0.5
; same with seeding from current time
i1 rnd31 1, 0.5, 0
i2 rnd31 1, 0.5
i3 rnd31 1, 0.5
AUTHOR
======
Istvan Varga
Nov 2001
------------------------------------------------------------------------
GEN40
This subroutine generates a continuous random distribution function starting
from the shape of a user-defined distribution histogram.
f# time size -40 shapetab
The shape of histogram must be stored in a previously defined table, in fact
shapetab argument must be filled with the number of such table.
Histogram shape can be generated with any other GEN routines. Since no
interpolation is used when GEN40 processes the translation, it is suggested
that the size of the table containing the histogram shape to be reasonably
big, in order to obtain more precision (however after the processing the
shaping-table can be destroyed in order to re-gain memory). In DirectCsound
it is possible to generate tables having non-power-of-two length by giving
a negative value to size argument.
This subroutine is designed to be used together with Cusrnd opcode
(see Cusrnd for more information).
------------------------------------------
GEN41
This subroutine generates a discrete random distribution function by giving
a list of numerical pairs.
f# time size -41 value1 prob1 value2 prob2 value3 prob3 ... valueN
probN
The first number of each pair is a value, and the second is the probability
of that value to be chosen by a random algorithm. Even if any number can
be assigned to the probability element of each pair, it is suggested to give
it a percent value, in order to make it clearer for the user. In DirectCsound
it is possible to generate a table having a non-power-of-two length by giving
a negative value to size argument.
This subroutine is designed to be used together with Dusrnd and
urd opcodes (see Dusrnd for more information).
------------------------------------------------------------------------
GEN42
This subroutine generates a random distribution function of discrete ranges
of values by giving a list of groups of three numbers.
f# time size -42 min1 max1 prob1 min2 max2 prob2 min3 max3 prob3 ... minN maxN probN
The first number of each group is a the minimum value of the first range,
the second is the maximum value and the third is the probability of that
an element belonging to that range of values can be chosen by a random
algorithm. Even if any number can be assigned to the probability element
of each group, it is suggested to give it a percent value, in order to make
it clearer to the user. In DirectCsound it is possible to generate a table
having a non-power-of-two length by giving a negative value to
size argument.
This subroutine is designed to be used together with Dusrnd and
urd opcodes (see Dusrnd for more information). Since both
Dusrnd and urd do not use any interpolation, it is suggested
to give a size reasonably big.
------------------------------------------------------------------------
duserrnd, cuserrnd
iout duserrnd itableNum
kout duserrnd ktableNum
aout duserrnd atableNum
iout = urd(itableNum)
kout = urd(ktableNum)
aout = urd(atableNum)
iout cuserrnd imin, imax, itableNum
kout cuserrnd kmin, kmax, ktableNum
aout cuserrnd amin, amax, atableNum
DESCRIPTION
Output is a controlled pseudo-random number series. In these cases, the random
distributions are created by the user.
INITIALIZATION
itableNum - number of table containing the random-distribution function.
Such table is generated by the user. See GEN40, GEN41 and GEN42. The table
length does not need to be a power of 2
imin - minimum range limit
imax - maximum range limit
PERFORMANCE
ktableNum - number of table containing the random-distribution function.
Such table is generated by the user. See GEN40, GEN41 and GEN42. The table
length does not need to be a power of 2
kmin - minimum range limit
kmax - maximum range limit
duserrnd (discrete user-defined-distribution random generator) generates
random values according to a discrete random distribution created by the
user. The user can create the discrete distribution histogram by using
GEN41. In order to create that table, the user has to define an arbitrary
amount of number pairs, the first number of each pair representing a value
and the second representing its probability (see GEN41 for more details).
urd is the same opcode as duserrnd, but can be used in function
fashion. When used as a function, the rate of generation depends by
the rate type of input variable XtableNum. In this case it
can be embedded into any formula. Table number can be varied at k-rate, allowing
to change the distribution histogram during the performance of a single note.
duserrnd is designed be used in algorithmic music generation.
duserrnd can also be used to generate values following a set of ranges
of probabilities by using distribution functions generated by GEN42
(See GEN 42 for more details). In this case, in order to simulate
continuous ranges, the length of table XtableNum should be
reasonably big, as duserrnd does not interpolate between table elements.
cuserrnd (continuous user-defined-distribution random generator)
generates random values according to a continuous random distribution
created by the user. In this case the shape of the distribution histogram
can be drawn or generated by any GEN routine. The table containing the shape
of such histogram must then be translated to a distribution function by means
of GEN40 (see GEN40 for more details). Then such function must
be assigned to the XtableNum argument of cuserrnd.
The output range can then be rescaled according to the Xmin
and Xmax arguments. cuserrnd linearly interpolates between
table elements, so it is not recommended for discrete distributions (GEN41
and GEN42).
For a tutorial about random distribution histograms and functions see:
D. Lorrain. "A panoply of stochastic cannons". In C. Roads, ed. 1989. Music
machine. Cambridge, Massachusetts: MIT press, pp. 351 - 379.
------------------------------------------------------------------------