commit bb7a046f8056de15265675b666a43b96f9ad7d85
parent fb59d0920be570106a8f7b1afa7978128d3d9234
Author: Matt Demanett <matt@demanett.net>
Date: Thu, 11 Jan 2018 00:49:03 -0500
Some rudimentary filter stuff.
Diffstat:
8 files changed, 356 insertions(+), 0 deletions(-)
diff --git a/res-src/Test-src.svg b/res-src/Test-src.svg
@@ -0,0 +1,146 @@
+<svg
+ version="1.1"
+ xmlns="http://www.w3.org/2000/svg"
+ xmlns:xlink="http://www.w3.org/1999/xlink"
+ width="45"
+ height="380"
+ viewBox="0 0 45 380"
+>
+ <style>
+ text {
+ fill: #333;
+ font-family: 'Roboto', sans-serif;
+ font-weight: bold;
+ }
+ text.title {
+ font-family: 'Comfortaa', sans-serif;
+ font-weight: normal;
+ }
+ text.brand {
+ font-family: 'Audiowide', sans-serif;
+ font-weight: bold;
+ }
+ </style>
+
+ <defs>
+ <symbol id="knob" viewBox="0 0 45px 45px">
+ <g transform="translate(22.5 22.5)">
+ <polyline points="-5,0 5,0" stroke-width="1" stroke="#00f" />
+ <polyline points="0,-5 0,5" stroke-width="1" stroke="#00f" />
+ <circle cx="0" cy="0" r="12.5" stroke-width="1" stroke="#00f" fill="none" />
+ </g>
+ </symbol>
+
+ <symbol id="knobguide" viewBox="0 0 45px 45px">
+ <g transform="translate(22.5 22.5)">
+ <g transform="rotate(-240) translate(15 0)">
+ <text font-size="5.0pt" transform="translate(3 0) rotate(240) translate(-2.2 2.2)">0</text>
+ </g>
+ <g transform="rotate(-210) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-180) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-150) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-120) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-90) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-60) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(-30) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(0) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(30) translate(15 0)">
+ <polyline points="0,0 2.5,0" stroke-width="0.3" stroke="#333" />
+ </g>
+ <g transform="rotate(60) translate(15 0)">
+ <text font-size="5.0pt" transform="translate(3 0) rotate(-60) translate(-4 2.2)">10</text>
+ </g>
+ </g>
+ </symbol>
+
+ <symbol id="input" viewBox="0 0 24px 24px">
+ <g transform="translate(12 12)">
+ <circle cx="0" cy="0" r="5" stroke-width="1" stroke="#0f0" fill="#0f0" />
+ <circle cx="0" cy="0" r="10.5" stroke-width="3" stroke="#0f0" fill="none" />
+ </g>
+ </symbol>
+
+ <symbol id="output" viewBox="0 0 24px 24px">
+ <g transform="translate(12 12)">
+ <circle cx="0" cy="0" r="5" stroke-width="1" stroke="#f00" fill="#f00" />
+ <circle cx="0" cy="0" r="10.5" stroke-width="3" stroke="#f00" fill="none" />
+ </g>
+ </symbol>
+ </defs>
+
+ <rect width="100%" height="100%" fill="#ddd" />
+ <polyline points="1,1 44,1 44,379 1,379 1,1" stroke="#e4e4e4" stroke-width="0.5" fill="none" />
+ <polyline points="0.5,0.5 44.5,0.5 44.5,379.5 0.5,379.5 0.5,0.5" stroke="#ebebeb" stroke-width="0.8" fill="none" />
+ <polyline points="0,0 45,0 45,380 0,380 0,0" stroke="#f2f2f2" stroke-width="1" fill="none" />
+
+ <!-- <polyline points="22.5,0 22.5,380" stroke-width="0.5" stroke="#0f0" /> -->
+ <!-- <rect width="45" height="10" fill="#0f0" transform="translate(0 68)" /> -->
+ <!-- <rect width="45" height="10" fill="#0f0" transform="translate(0 127)" /> -->
+ <!-- <rect width="45" height="10" fill="#0f0" transform="translate(0 177)" /> -->
+
+ <g transform="rotate(-90) translate(-376 13)">
+ <text class="title" font-size="7pt" letter-spacing="2.5px">test</text>
+ <g transform="translate(0 12)">
+ <text class="brand" font-size="7pt" letter-spacing="2px">BGA</text>
+ <rect width="3.0" height="3" fill="#ddd" transform="translate(11.5 -5)" />
+ </g>
+ </g>
+
+ <g transform="translate(0 25)">
+ <text font-size="6pt" letter-spacing="2px" transform="translate(5.5 0)">P1</text>
+ <use id="PARAM1_PARAM" xlink:href="#knob" transform="translate(0 -6)" />
+ <use xlink:href="#knobguide" transform="translate(0 -6)" />
+ </g>
+
+ <g transform="translate(0 63)">
+ <g transform="translate(5.5 0)">
+ <rect width="34" height="38" rx="5" fill="#fafafa" />
+ <use id="CV1_INPUT" xlink:href="#input" transform="translate(5 3)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(12.5 35)">CV</text>
+ </g>
+ </g>
+
+ <g transform="translate(0 125)">
+ <text font-size="6pt" letter-spacing="2px" transform="translate(5.5 0)">P2</text>
+ <use id="PARAM2_PARAM" xlink:href="#knob" transform="translate(0 -6)" />
+ <use xlink:href="#knobguide" transform="translate(0 -6)" />
+ </g>
+
+ <g transform="translate(0 165)">
+ <g transform="translate(5.5 0)">
+ <rect width="34" height="38" rx="5" fill="#fafafa" />
+ <use id="CV2_INPUT" xlink:href="#input" transform="translate(5 3)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(12.5 35)">CV</text>
+ </g>
+ </g>
+ <g transform="translate(0 255)">
+ <g transform="translate(5.5 0)">
+ <rect width="34" height="10" fill="#fafafa" transform="translate(0 63)" />
+ <rect width="34" height="70" rx="5" fill="#fafafa" />
+ <use id="IN_INPUT" xlink:href="#input" transform="translate(5 3)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(12.5 35)">IN</text>
+ </g>
+ <g transform="translate(5.5 41)">
+ <rect width="34" height="10" fill="#bbb" transform="translate(0 -3)" />
+ <rect width="34" height="35" rx="5" fill="#bbb" />
+ <use id="OUT_OUTPUT" xlink:href="#output" transform="translate(5 0)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(8.5 32)">OUT</text>
+ </g>
+ </g>
+</svg>
diff --git a/res/Test.svg b/res/Test.svg
Binary files differ.
diff --git a/src/Test.cpp b/src/Test.cpp
@@ -0,0 +1,94 @@
+
+#include "bogaudio.hpp"
+#include "dsp/dsp.hpp"
+
+using namespace bogaudio::dsp;
+
+struct Test : Module {
+ enum ParamsIds {
+ PARAM1_PARAM,
+ PARAM2_PARAM,
+ NUM_PARAMS
+ };
+
+ enum InputsIds {
+ CV1_INPUT,
+ CV2_INPUT,
+ IN_INPUT,
+ NUM_INPUTS
+ };
+
+ enum OutputsIds {
+ OUT_OUTPUT,
+ NUM_OUTPUTS
+ };
+
+ enum LightsIds {
+ NUM_LIGHTS
+ };
+
+ LowPassFilter _lpf;
+
+ Test()
+ : Module(NUM_PARAMS, NUM_INPUTS, NUM_OUTPUTS, NUM_LIGHTS)
+ , _lpf(44100.0, 1000.0, 1.0)
+ {
+ reset();
+ }
+
+ virtual void reset() override;
+ virtual void step() override;
+};
+
+void Test::reset() {
+}
+
+void Test::step() {
+ if (!inputs[IN_INPUT].active || !outputs[OUT_OUTPUT].active) {
+ return;
+ }
+
+ _lpf.setParams(
+ engineGetSampleRate(),
+ 10000.0 * clampf(params[PARAM1_PARAM].value, 0.0, 1.0),
+ std::max(10.0 * clampf(params[PARAM2_PARAM].value, 0.0, 1.0), 0.1)
+ );
+ outputs[OUT_OUTPUT].value = _lpf.next(inputs[IN_INPUT].value);
+}
+
+
+TestWidget::TestWidget() {
+ Test *module = new Test();
+ setModule(module);
+ box.size = Vec(RACK_GRID_WIDTH * 3, RACK_GRID_HEIGHT);
+
+ {
+ SVGPanel *panel = new SVGPanel();
+ panel->box.size = box.size;
+ panel->setBackground(SVG::load(assetPlugin(plugin, "res/Test.svg")));
+ addChild(panel);
+ }
+
+ addChild(createScrew<ScrewSilver>(Vec(0, 0)));
+ addChild(createScrew<ScrewSilver>(Vec(box.size.x - 15, 365)));
+
+ // generated by svg_widgets.rb
+ auto param1ParamPosition = Vec(9.5, 28.5);
+ auto param2ParamPosition = Vec(9.5, 128.5);
+
+ auto cv1InputPosition = Vec(10.5, 66.0);
+ auto cv2InputPosition = Vec(10.5, 168.0);
+ auto inInputPosition = Vec(10.5, 258.0);
+
+ auto outOutputPosition = Vec(10.5, 296.0);
+ // end generated by svg_widgets.rb
+
+ addParam(createParam<Knob26>(param1ParamPosition, module, Test::PARAM1_PARAM, 0.0, 1.0, 0.5));
+ addParam(createParam<Knob26>(param2ParamPosition, module, Test::PARAM2_PARAM, 0.0, 1.0, 0.5));
+
+ addInput(createInput<Port24>(cv1InputPosition, module, Test::CV1_INPUT));
+ addInput(createInput<Port24>(cv2InputPosition, module, Test::CV2_INPUT));
+ addInput(createInput<Port24>(inInputPosition, module, Test::IN_INPUT));
+
+ addOutput(createOutput<Port24>(outOutputPosition, module, Test::OUT_OUTPUT));
+}
diff --git a/src/bogaudio.cpp b/src/bogaudio.cpp
@@ -28,4 +28,8 @@ void init(rack::Plugin *p) {
p->addModel(createModel<SampleHoldWidget>("Bogaudio", "Bogaudio-SampleHold", "S&H", SAMPLE_AND_HOLD_TAG, DUAL_TAG, UTILITY_TAG));
p->addModel(createModel<SwitchWidget>("Bogaudio", "Bogaudio-Switch", "Switch", SWITCH_TAG, UTILITY_TAG));
p->addModel(createModel<VCAWidget>("Bogaudio", "Bogaudio-VCA", "VCA", AMPLIFIER_TAG, DUAL_TAG, UTILITY_TAG));
+
+#ifdef EXPERIMENTAL
+ p->addModel(createModel<TestWidget>("Bogaudio", "Bogaudio-Test", "Test"));
+#endif
}
diff --git a/src/bogaudio.hpp b/src/bogaudio.hpp
@@ -76,4 +76,9 @@ struct VCAWidget : ModuleWidget {
VCAWidget();
};
+
+struct TestWidget : ModuleWidget {
+ TestWidget();
+};
+
} // namespae bogaudio
diff --git a/src/dsp/dsp.hpp b/src/dsp/dsp.hpp
@@ -5,5 +5,6 @@
#include "buffer.hpp"
#include "analyzer.hpp"
+#include "filter.hpp"
#include "oscillator.hpp"
#include "noise.hpp"
diff --git a/src/dsp/filter.cpp b/src/dsp/filter.cpp
@@ -0,0 +1,57 @@
+
+#include <math.h>
+
+#include "dsp.hpp"
+
+using namespace bogaudio::dsp;
+
+// See: http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
+
+void BiquadFilter::setParams(float b0, float b1, float b2, float a0, float a1, float a2) {
+ _b0 = b0 / a0;
+ _b1 = b1 / a0;
+ _b2 = b2 / a0;
+ _a1 = a1 / a0;
+ _a2 = a2 / a0;
+ // printf("Biquad set params: b0=%f b1=%f b2=%f a1=%f a2=%f\n", _b0, _b1, _b2, _a1, _a2);
+}
+
+float BiquadFilter::next(float sample) {
+ _x[2] = _x[1];
+ _x[1] = _x[0];
+ _x[0] = sample;
+
+ _y[2] = _y[1];
+ _y[1] = _y[0];
+ _y[0] = _b0 * _x[0];
+ _y[0] += _b1 * _x[1];
+ _y[0] += _b2 * _x[2];
+ _y[0] -= _a1 * _y[1];
+ _y[0] -= _a2 * _y[2];
+
+ return _y[0];
+}
+
+
+void LowPassFilter::setParams(float sampleRate, float cutoff, float q) {
+ if (_sampleRate == sampleRate && _cutoff == cutoff && _q == q) {
+ return;
+ }
+ // printf("\nLPF set param: sr=%f c=%f q=%f\n", _sampleRate, _cutoff, _q);
+ _sampleRate = sampleRate;
+ _cutoff = cutoff;
+ _q = q;
+
+ float w0 = 2.0 * M_PI * _cutoff / _sampleRate;
+ float cosw0 = cosf(w0);
+ float alpha = sinf(w0) / (2.0 * _q);
+
+ _biquad.setParams(
+ (1.0 - cosw0) / 2.0,
+ 1.0 - cosw0,
+ (1.0 - cosw0) / 2.0,
+ 1.0 + alpha,
+ -2.0 * cosw0,
+ 1.0 - alpha
+ );
+}
diff --git a/src/dsp/filter.hpp b/src/dsp/filter.hpp
@@ -0,0 +1,49 @@
+
+namespace bogaudio {
+namespace dsp {
+
+struct Filter {
+ Filter() {}
+ virtual ~Filter() {}
+
+ virtual float next(float sample) = 0;
+};
+
+struct BiquadFilter : Filter {
+ float _b0 = 0.0;
+ float _b1 = 0.0;
+ float _b2 = 0.0;
+ float _a1 = 0.0;
+ float _a2 = 0.0 ;
+
+ float _x[3] {};
+ float _y[3] {};
+
+ BiquadFilter() {}
+
+ void setParams(float b0, float b1, float b2, float a0, float a1, float a2);
+ virtual float next(float sample) override;
+};
+
+struct LowPassFilter : Filter {
+ float _sampleRate;
+ float _cutoff;
+ float _q;
+
+ BiquadFilter _biquad;
+
+ LowPassFilter(float sampleRate, float cutoff, float q)
+ : _sampleRate(sampleRate)
+ , _cutoff(cutoff)
+ , _q(q)
+ {
+ }
+
+ void setParams(float sampleRate, float cutoff, float q);
+ virtual float next(float sample) override {
+ return _biquad.next(sample);
+ }
+};
+
+} // namespace dsp
+} // namespace bogaudio