.bp F STATEMENT (or FUNCTION TABLE STATEMENT) .i \fBf\fR p1 p2 p3 p4 ... .e This causes a GEN subroutine to place values in a stored function table for use by instruments. PFIELDS .i p1 Table number (from 1 to 100) by which the stored function will be known. A negative number requests that the table be destroyed. .sp .5 p2 Action time of function generation (or destruction) in beats .sp .5 p3 Size of function table (i.e. number of points). Must be a power of 2, or a power-of-2 plus 1 (see below). Maximum table size is 16777216 (2**24) points. .sp .5 p4 Number of the GEN routine to be called (see GEN ROUTINES). A negative value will cause rescaling to be omitted. .sp .5 p5 | p6 | Parameters whose meaning is determined by the particular GEN routine. . | . | . | .e SPECIAL CONSIDERATIONS Function tables are arrays of floating-point values. Arrays can be of any length in powers of 2; space allocation always provides for 2**n points plus an additional \fIguard point\fR. The guard point value, used during interpolated lookup, can be automatically set to reflect the table's purpose: If \fIsize\fR is an exact power of 2, the guard point will be a copy of the first point; this is appropriate for \fIinterpolated wrap-around\fR lookup as in \fBoscili,\fR etc., and should even be used for non-interpolating .B oscil for safe consistency. If \fIsize\fR is set to 2**n + 1, the guard point value automatically extends the contour of table values; this is appropriate for single-scan functions such in \fBenvlpx, oscil1, oscil1i\fR, etc. Table space is allocated in primary memory, along with instrument data space. The maximum table number has a soft limit of 100; this can be extended if required. An existing function table can be removed by an .B f statement containing a negative p1 and an appropriate action time. A function table is also be removed by the generation of another table with the same p1. Functions are not automatically erased at the end of a score section. p2 action time is treated in the same way as in .B i statements with respect to sorting and modification by .B t statements. If an .B f statement and an .B i statement have the same p2, the sorter gives the .B f statement precedence so that the function table will be available during note initialization. An \fBf 0\fR statement (zero p1, positive p2) may be used to create an action time with no associated action. Such time markers are useful for padding out a score section (see .B s statement). .bp I STATEMENT (INSTRUMENT or NOTE STATEMENT) .i \fBi\fR p1 p2 p3 p4 ... .e This statement calls for an instrument to be made active at a specific time and for a certain duration. The parameter field values are passed to that instrument prior to its Initialization, and remain valid throughout its Performance. PFIELDS .i p1 Instrument number, usually a non-negative integer. An optional fractional part can provide an additional tag for specifying ties between particular notes of consecutive clusters. A negative p1 (including tag) can be used to turn off a particular 'held' note. .sp .5 p2 Starting time in arbitrary units called beats. .sp .5 p3 Duration time in beats (usually positive). A negative value will initiate a held note (see also \fBihold\fR). A zero value will invoke an initialization pass without performance (see also \fBinstr\fR). .sp .5 p4 | p5 | Parameters whose significance is determined by the instrument. . | . | .e SPECIAL CONSIDERATIONS Beats are evaluated as seconds unless there is a .B t statement in this section. Starting or action times are relative to the beginning of a section (see .B s statement), which is assigned time 0. Note statements within a section may be placed in any order. Before being sent to an orchestra, unordered score statements must first be processed by Sorter, which will reorder them by ascending p2 value. Notes with the same p2 value will be ordered by ascending p1; if the same p1, then by ascending p3. Notes may be stacked, i.e., a single instrument can perform any number of notes simultaneously. (The necessary copies of the instrument's data space will be allocated dynamically by the orchestra loader.) Each note will normally turn off when its p3 duration has expired. However, an instrument may modify its own duration by modifying its p3 value during note initialization. An instrument may be turned on and left to perform indefinitely either by giving it a negative p3 or by including an \fBihold\fR in its I-time code. If a held note is active, an .B i statement \fIwith matching p1\fR will not cause a new allocation but will take over the data space of the held note. The new pfields (including p3) will now be in effect, and an I-time pass will be executed in which the units can either be newly initialized or allowed to continue as required for a tied note (see \fBtigoto\fR). A held note may be succeeded either by another held note or by a note of finite duration. A held note will continue to perform across section endings (see .B s statement). It is halted only by \fBturnoff\fR or by an .B i statement with negative matching p1 or by an .B e statement. .bp A STATEMENT (or ADVANCE STATEMENT) .i \fBa\fR p1 p2 p3 .e This causes score time to be advanced by a specified amount without producing sound samples. PFIELDS .i p1 carries no meaning. Usually zero p2 Action time, in beats, at which advance is to begin. p3 Durational span (distance in beats) of time advance. p4,p5, etc carry no meaning. .e SPECIAL CONSIDERATIONS This statement allows the beat count within a score section to be advanced without generating intervening sound samples. This can be of use when a score section is incomplete (the beginning or middle is missing) and the user does not wish to generate and listen to a lot of silence. p2 action time and p3 distance are treated as in .B i statements, with respect to sorting and modification by .B t statements. An .B a statement will be temporarily inserted in the score by the Score Extract feature when the extracted segment begins later than the start of a Section. The purpose of this is to preserve the beat count and time count of the original score for the benefit of the peak amplitudes messages which are reported on the user console. Whenever an .B a statement is encountered by a performing orchestra, its presence and effect will be reported on the user's console. .bp T STATEMENT (TEMPO STATEMENT) .i \fBt\fR p1 p2 p3 p4 ..... (unlimited) .e This statement sets the tempo and specifies the accelerations and decelerations for the current section. This is done by converting beats into seconds. PFIELDS .i p1 must be zero p2 initial tempo in beats per minute p3, p5, p7, ... times in beats (in non-decreasing order) p4, p6, p8, ... tempi for the referenced beat times .e SPECIAL CONSIDERATIONS Time and Tempo-for-that-time are given as ordered couples that define points on a "tempo vs time" graph. (The time-axis here is in beats so is not necessarily linear.) The beat-rate of a Section can be thought of as a movement from point to point on that graph: motion between two points of equal height signifies constant tempo, while motion between two points of unequal height will cause an accelarando or ritardando accordingly. The graph can contain discontinuities: two points given equal times but different tempi will cause an immediate tempo change. Motion between different tempos over non-zero time is inverse linear. That is, an accelarando between two tempos M1 and M2 proceeds by linear interpolation of the single-beat durations from 60/M1 to 60/M2. The first tempo given must be for beat 0. A tempo, once assigned, will remain in effect from that time-point unless influenced by a succeeding tempo, i.e. the last specified tempo will be held to the end of the section. A .B t statement applies only to the score section in which it appears. Only one .B t statement is meaningful in a section; it can be placed anywhere within that section. If a score section contains no .B t statement, then beats are interpreted as seconds (i.e. with an implicit t 0 60 statement). .bp S STATEMENT .i \fBs\fR anything .e The .B s statement marks the end of a section. PFIELDS All pfields are ignored. SPECIAL CONSIDERATIONS Sorting of the \fBi, f\fR and .B a statements by action time is done section by section. Time warping for to the .B t statement is done section by section. All action times within a section are relative to its beginning. A section statement establishes a new relative time of 0, but has no other reinitializing effects (e.g. stored function tables are preserved across section boundaries). A section is considered complete when all action times and finite durations have been satisfied (i.e., the "length" of a section is determined by the last occurring action or turn-off). A section can be extended by the use of an \fBf 0\fR statement. A section ending automatically invokes a Purge of inactive instrument and data spaces. Since score statements are sorted in memory, the maximum number of statements in a single section depends upon memory size. That limit is rarely encountered, but for small systems of say 128K bytes, an average of 10 pfields or 50 characters per statement should allow at least 500 statements per section. For the end of the final section of a score, the .B s statement is optional; the .B e statement may be used instead. .bp E STATEMENT .i \fBe\fR anything .e This statement may be used to mark the end of the last section of the score. PFIELDS All pfields are ignored SPECIAL CONSIDERATIONS The .B e statement is contextually identical to an .B s statement. Additionally, the .B e statement terminates all signal generation (including indefinite performance) and closes all input and output files. If an .B e statement occurs before the end of a score, all subsequent score lines will be ignored. The .B e statement is optional in a score file yet to be sorted. If a score file has no .B e statement, then Sort processing will supply one. .bp