README.md

@@ -1,7 +1,6 @@
 # nymph
 
-A [Nim] library for writing audio and MIDI plugins conforming to the [LV2]
+A [Nim] library for writing audio and MIDI plugins conforming to the [LV2] standard
-standard
 
 
 ## Examples
@@ -28,59 +27,51 @@ the basename of the plugin's LV2 bundle dir.
 
 Currently, there are just a few other example plugins:
 
-* [`miditranspose`](./examples/miditranspose_plugin.nim): shows how to handle
+* `miditranspose`: shows how to handle receiving and sending MIDI events.
-  receiving and sending MIDI events.
+* `multimodefilter`: shows a multimode state-variable filter implementation
-* [`multimodefilter`](./examples/multimodefilter_plugin.nim): shows a
+  ported from C++ to Nim.
-  multimode state-variable filter implementation ported from C++ to Nim.
+* `tiltfilter`: shows a multimode tilt equalizer filter implementation ported
-* [`tiltfilter`](./examples/titltfilter_plugin.nim): shows a multimode tilt
+  from Rust to Nim.
-  equalizer filter implementation ported from Rust to Nim.
+* `faustlpf`: shows how to integrate DSP C code generated from a [FAUST]
-* [`faustlpf`](./examples/faustlpf_plugin.nim): shows how to integrate DSP C
+  source file in Nim (in this example the FAUST code implements a simple
-  code generated from a [FAUST] source file in Nim (in this example the FAUST
+  non-resonant low-pass filter from the FAUST standard library).
-  code implements a simple non-resonant low-pass filter from the FAUST
-  standard library).
-
 
 ## How To
 
-**Note:** I'll use `mydsp` as the base name for the new plugin in the
+* Install this library:
-examples below. Substitute your own plugin basename wherever you see it used
-below.
 
-1. Install this library:
+        nimble install https://git.0x20.eu/chris/nymph
 
-      nimble install https://github.com/SpotlightKid/nymph.git
+* Copy `examples/amp.lv2` and `examples/amp.nim` into your project and rename
+  them as you like (also rename `amp.lv2/amp.ttl`). I'll use `myplugin` as the
+  base name in the examples below.
 
-1. Make a directory named `mydsp.lv2` and copy `examples/amp.lv2/manifest.ttl`
+* Edit `myplugin.lv2/manifest.ttl`:
-    into it. Also copy `examples/amp.lv2/amp.ttl` to `mydsp.lv2/mydsp.ttl`.
-
-1. Copy `examples/amp_plugin.nim` into your project as `mydsp_plugin.nim`.
-
-1. Edit `mydsp.lv2/manifest.ttl`:
     * Change the plugin URI.
     * Change the plugin's shared library name defined via `lv2:binary` to
-     `libmydsp.so`.
+      `libmyplugin.so`.
-   * Change file name referenced via `rdfs:seeAlso` to `mydsp.ttl`.
+    * Change file name referenced via `rdfs:seeAlso` to `myplugin.ttl`.
 
-1. Edit `mydsp.lv2/mydsp.ttl`:
+* Edit `myplugin.lv2/myplugin.ttl`:
     * Change the plugin URI.
     * Define audio, control and atom ports as needed.
 
-1. Edit `mydsp_plugin.nim`:
+* Edit `myplugin.nim`:
     * Change the `PluginUri` constant at the top.
     * Change the `PluginPort` enum and list the ports in the order defined in
-     `mydsp.ttl`.
+      `myplugin.ttl`.
     * Rename and update the definition of the `AmpPlugin` object type and
-     define its members with the appropriate data types for the plugin ports
+      define its members with the appropriate data type for the plugin port
       they will be connected to. Update the type name in the `instantiate`,
       `deactivate`, `connectPorts` and `run` procs.
     * Update and extend the `case` statement in `connectPort` to connect ports
       to your plugin object instance members.
     * Implement your DSP code in the `run` proc.
 
-1. Compile the plugin shared library object with:
+* Compile the plugin shared library object with:
 
         nim c --app:lib --noMain:on --mm:arc \
-            --out:mydsp.lv2/libmydsp.so mydsp_plugin.nim
+            --out:myplugin.lv2/libmyplugin.so myplugin.nim
 
     See the definition of the `build_ex` task in the
     [nymph.nimble](./nymph.nimble#L67) file on how to create a nimble task

examples/faustlpf_plugin.nim

@@ -2,22 +2,24 @@
 
 import nymph
 
-{.emit: """#include "lpf.h"""".}
+{.emit: "#include \"lpf.h\"".}
 
 const
     PluginUri = "urn:nymph:examples:faustlpf"
+    minFreq = 16.0
+    maxFreq = 15_000.0
 
 type
+    SampleBuffer = UncheckedArray[cfloat]
+
     faustlpf {.importc, header: "lpf.h".} = object
-        # struct field representing the value of the FAUST UI element,
+        # struct field, which represents the value of the
-        # which controls the filter cutoff frequency
+        # FAUST UI element, which controls the cutoff
         fHslider0: cfloat
 
     PluginPort {.pure.} = enum
         Input, Output, Frequency
 
-    SampleBuffer = UncheckedArray[cfloat]
-
     FaustLPFPlugin = object
         input: ptr SampleBuffer
         output: ptr SampleBuffer
@@ -32,8 +34,6 @@ proc initfaustlpf(dsp: ptr faustlpf, sample_rate: cint) {.importc.}
 proc instanceClearfaustlpf(dsp: ptr faustlpf) {.importc.}
 proc computefaustlpf(dsp: ptr faustlpf, count: cint, inputs, outputs: ptr ptr SampleBuffer) {.importc.}
 
-proc NimMain() {.cdecl, importc.}
-
 
 proc instantiate(descriptor: ptr Lv2Descriptor; sampleRate: cdouble;
                  bundlePath: cstring; features: ptr UncheckedArray[ptr Lv2Feature]):
@@ -66,7 +66,8 @@ proc activate(instance: Lv2Handle) {.cdecl.} =
 
 proc run(instance: Lv2Handle; nSamples: cuint) {.cdecl.} =
     let plug = cast[ptr FaustLPFPlugin](instance)
-    plug.flt.fHslider0 = plug.freq[]
+    plug.flt.fHslider0 = plug.freq[].clamp(minFreq, maxFreq)
+
     computefaustlpf(plug.flt, nSamples.cint, addr plug.input, addr plug.output)
 
 
@@ -84,6 +85,9 @@ proc extensionData(uri: cstring): pointer {.cdecl.} =
     return nil
 
 
+proc NimMain() {.cdecl, importc.}
+
+
 proc lv2Descriptor(index: cuint): ptr Lv2Descriptor {.
                    cdecl, exportc, dynlib, extern: "lv2_descriptor".} =
     NimMain()

examples/lpf.h

@@ -5,7 +5,7 @@ license: "MIT"
 name: "FaustLPF"
 version: "0.1.0"
 Code generated with Faust 2.74.6 (https://faust.grame.fr)
-Compilation options: -a ./examples/minarch.h -lang c -rui -ct 1 -fm def -cn faustlpf -es 1 -mcd 16 -mdd 1024 -mdy 33 -single -ftz 0 -vec -lv 0 -vs 32
+Compilation options: -a ./examples/minarch.h -lang c -ct 1 -cn faustlpf -es 1 -mcd 16 -mdd 1024 -mdy 33 -single -ftz 0 -vec -lv 0 -vs 32
 ------------------------------------------------------------ */
 
 #ifndef  __faustlpf_H__
@@ -17,8 +17,14 @@ Compilation options: -a ./examples/minarch.h -lang c -rui -ct 1 -fm def -cn faus
  FAUST Architecture File for generating a very minimal C interface
  ************************************************************************/
 
+#include <math.h>
+#include <stdio.h>
+
 #include "faust/gui/CInterface.h"
 
+#define max(a,b) ((a < b) ? b : a)
+#define min(a,b) ((a < b) ? a : b)
+
 /******************************************************************************
  VECTOR INTRINSICS
 *******************************************************************************/
@@ -41,7 +47,6 @@ extern "C" {
 #define RESTRICT __restrict__
 #endif
 
-#include "faust/dsp/fastmath.cpp"
 #include <math.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -81,7 +86,7 @@ void deletefaustlpf(faustlpf* dsp) {
 
 void metadatafaustlpf(MetaGlue* m) { 
 	m->declare(m->metaInterface, "author", "Christopher Arndt");
-	m->declare(m->metaInterface, "compile_options", "-a ./examples/minarch.h -lang c -rui -ct 1 -fm def -cn faustlpf -es 1 -mcd 16 -mdd 1024 -mdy 33 -single -ftz 0 -vec -lv 0 -vs 32");
+	m->declare(m->metaInterface, "compile_options", "-a ./examples/minarch.h -lang c -ct 1 -cn faustlpf -es 1 -mcd 16 -mdd 1024 -mdy 33 -single -ftz 0 -vec -lv 0 -vs 32");
 	m->declare(m->metaInterface, "copyright", "Christopher Arndt, 2024");
 	m->declare(m->metaInterface, "filename", "lpf.dsp");
 	m->declare(m->metaInterface, "filters.lib/fir:author", "Julius O. Smith III");
@@ -186,7 +191,7 @@ void buildUserInterfacefaustlpf(faustlpf* dsp, UIGlue* ui_interface) {
 void computefaustlpf(faustlpf* dsp, int count, FAUSTFLOAT** RESTRICT inputs, FAUSTFLOAT** RESTRICT outputs) {
 	FAUSTFLOAT* input0_ptr = inputs[0];
 	FAUSTFLOAT* output0_ptr = outputs[0];
-	float fSlow0 = dsp->fConst1 * fmaxf(16.0f, fminf(1.5e+04f, (float)(dsp->fHslider0)));
+	float fSlow0 = dsp->fConst1 * (float)(dsp->fHslider0);
 	float fRec1_tmp[36];
 	float* fRec1 = &fRec1_tmp[4];
 	float fZec0[32];
@@ -231,7 +236,7 @@ void computefaustlpf(faustlpf* dsp, int count, FAUSTFLOAT** RESTRICT inputs, FAU
 		{
 			int i;
 			for (i = 0; i < vsize; i = i + 1) {
-				fZec0[i] = fast_tanf(dsp->fConst3 * fRec1[i]);
+				fZec0[i] = tanf(dsp->fConst3 * fRec1[i]);
 			}
 		}
 		/* Vectorizable loop 2 */
@@ -323,7 +328,7 @@ void computefaustlpf(faustlpf* dsp, int count, FAUSTFLOAT** RESTRICT inputs, FAU
 		{
 			int i;
 			for (i = 0; i < vsize; i = i + 1) {
-				fZec0[i] = fast_tanf(dsp->fConst3 * fRec1[i]);
+				fZec0[i] = tanf(dsp->fConst3 * fRec1[i]);
 			}
 		}
 		/* Vectorizable loop 2 */

examples/minarch.h

@@ -4,8 +4,14 @@
  FAUST Architecture File for generating a very minimal C interface
  ************************************************************************/
 
+#include <math.h>
+#include <stdio.h>
+
 #include "faust/gui/CInterface.h"
 
+#define max(a,b) ((a < b) ? b : a)
+#define min(a,b) ((a < b) ? a : b)
+
 /******************************************************************************
  VECTOR INTRINSICS
 *******************************************************************************/