Module synfx_dsp_jit::stdlib

Definition of the Intermediate Representation for the JIT compiler.

This is a quick guide of the intermediate language you can pass into the JIT compiler in form of an crate::ASTNode tree.

For a reference of the AST itself I recommend looking at crate::ASTNode and crate::ASTBinOp. They are pretty self explanatory.

Make sure to visit crate::ast::build too, it is an easy way to build an AST data structure.

Global Variables

There are multiple different kinds of variables you can access:

• Predefined crate::DSPFunction Parameters (available in every function):
  • in1 - First channel input
  • in2 - Second channel input
  • alpha - Alpha parameter input
  • beta - Beta parameter input
  • delta - Delta parameter input
  • gamma - Gamma parameter input
  • &sig1 - Writeable signal channel 1 output
  • &sig2 - Writeable signal channel 2 output
• Global Constants
  • PI - 3.14159…
  • TAU - 2*PI
  • E - Eulers number
  • 1PI - 1/PI
  • 2PI - 2/PI
  • PI2 - PI/2
  • PI3 - PI/3
  • PI4 - PI/4
  • PI6 - PI/6
  • PI8 - PI/8
  • 1SQRT2 - 1/sqrt(2)
  • 1SQRT_PI - 1/sqrt(PI)
  • LN2 - Ln(2)
  • LN10 - Ln(10)
• Global Variables / Auxilary Variables:
  • $srate - The current sample rate in Hz
  • $israte - The current sample rate in 1.0 / Hz
  • $reset - Is 1.0 directly after the very first initialization and after an explicit call to crate::DSPFunction::reset. Otherwise it’s 0.0.
• Persistent Variables (persistent across multiple calls, until a reset):
  • *... - Any variable that starts with a * is stored across multiple calls.
  • Note: If you need more (longer) persistent variables, across resets too, use the atomw/atomr nodes!
• Multiple Return Value Accessors
  • First return value does not exist as variable, it just is the result of the AST node itself, or the result of the node function.
  • %1 - Second return value
  • %2 - Third return value
  • %3 - Fourth return value
  • %4 - Fifth return value
  • %5 - Sixth return value

DSP Nodes

I heavily recommend checking out HexoSynth if you plan to use synfx-dsp-jit, it offers a graphical environment for trying out all the following nodes in real time in a visual programming language (called WBlockDSP):

DSPNodeType name	Inputs	Outputs	Description
accum	input, reset	sum	Accumulator, sums up the input
phase	frequency, reset	phase	Phase oscillator
sin	radians	sine	Sine function
/%	a, b	div, rem	Computes the float division and remainder of a and b
atomr	index	value	Reads an atomic float from a shared buffer at the given index
atomr~	index	value	Reads a linear interpolated atomic float from a shared buffer at the given index
atomw	index, value	value	Writes an atomic float into a shared buffer at the given index
s&h	input, set	value	A sample & hold node that samples it’s input on a rising edge at ‘set’.
s&h~	input, set	value	A sample & hold node that continously samples it’s input if ‘set’ is set.

Buffers and Tables

You can pass a configuration to crate::DSPNodeContext::new which lets you define the number of possible buffers and a set of tables. Double precision buffers have to be declared by the JIT AST itself using crate::ASTNode::BufDeclare.

Tables are vectors of single precision floats, which are provided by the caller/user of crate::DSPNodeContext at creation time. You can however swap out the tables at runtime later with others. Either directly by accessing crate::DSPFunction::with_dsp_state or via the crate::engine::CodeEngine::send_table method.

Structs

AccumNodeState

PhaseNodeState

SHLNodeState

SHNodeState

Functions

get_standard_library

Creates a crate::context::DSPNodeTypeLibrary that contains a bunch of standard components as seem fit by the synfx-dsp-jit crate developer.