From f40d3343fb00d612fd6c837df96ee7a0dcc64530 Mon Sep 17 00:00:00 2001
From: Andrew Belt <andrewpbelt@gmail.com>
Date: Mon, 31 Dec 2018 15:41:28 -0500
Subject: [PATCH] Add polyphony to ports and wires

---
 include/engine/Input.hpp  | 14 ++++----------
 include/engine/Output.hpp |  9 ++-------
 include/engine/Port.hpp   | 34 ++++++++++++++++++++++++++++++++++
 src/app/WireWidget.cpp    | 21 +++++++++++++++------
 src/engine/Wire.cpp       | 11 ++++++++---
 5 files changed, 63 insertions(+), 26 deletions(-)
 create mode 100644 include/engine/Port.hpp

diff --git a/include/engine/Input.hpp b/include/engine/Input.hpp
index 9a908b25..201f2c8a 100644
--- a/include/engine/Input.hpp
+++ b/include/engine/Input.hpp
@@ -1,21 +1,15 @@
 #pragma once
 #include "common.hpp"
-#include "engine/Light.hpp"
+#include "engine/Port.hpp"
 
 
 namespace rack {
 
 
-struct Input {
-	/** Voltage of the port, zero if not plugged in. Read-only by Module */
-	float value = 0.f;
-	/** Whether a wire is plugged in */
-	bool active = false;
-	Light plugLights[2];
-
+struct Input : Port {
 	/** Returns the value if a wire is plugged in, otherwise returns the given default value */
-	float normalize(float normalValue) {
-		return active ? value : normalValue;
+	float normalize(float normalValue, int index = 0) {
+		return active ? getValue(index) : normalValue;
 	}
 };
 
diff --git a/include/engine/Output.hpp b/include/engine/Output.hpp
index b3084e40..db938435 100644
--- a/include/engine/Output.hpp
+++ b/include/engine/Output.hpp
@@ -1,17 +1,12 @@
 #pragma once
 #include "common.hpp"
-#include "engine/Light.hpp"
+#include "engine/Port.hpp"
 
 
 namespace rack {
 
 
-struct Output {
-	/** Voltage of the port. Write-only by Module */
-	float value = 0.f;
-	/** Whether a wire is plugged in */
-	bool active = false;
-	Light plugLights[2];
+struct Output : Port {
 };
 
 
diff --git a/include/engine/Port.hpp b/include/engine/Port.hpp
new file mode 100644
index 00000000..2f2f146a
--- /dev/null
+++ b/include/engine/Port.hpp
@@ -0,0 +1,34 @@
+#pragma once
+#include "common.hpp"
+#include "engine/Light.hpp"
+
+
+namespace rack {
+
+
+static const int PORT_MAX_CHANNELS = 16;
+
+
+struct Port {
+	/** Voltage of the port */
+	union {
+		float value;
+		float values[PORT_MAX_CHANNELS];
+	};
+	/** Number of polyphonic channels */
+	int numChannels = 1;
+	/** Whether a wire is plugged in */
+	bool active = false;
+	Light plugLights[2];
+
+	float getValue(int index = 0) {
+		return values[index];
+	}
+
+	void setValue(float value, int index = 0) {
+		this->values[index] = value;
+	}
+};
+
+
+} // namespace rack
diff --git a/src/app/WireWidget.cpp b/src/app/WireWidget.cpp
index ee8510ea..d04cd560 100644
--- a/src/app/WireWidget.cpp
+++ b/src/app/WireWidget.cpp
@@ -31,14 +31,15 @@ static void drawPlug(NVGcontext *vg, math::Vec pos, NVGcolor color) {
 	nvgFill(vg);
 }
 
-static void drawWire(NVGcontext *vg, math::Vec pos1, math::Vec pos2, NVGcolor color, float tension, float opacity) {
+static void drawWire(NVGcontext *vg, math::Vec pos1, math::Vec pos2, NVGcolor color, float width, float tension, float opacity) {
 	NVGcolor colorShadow = nvgRGBAf(0, 0, 0, 0.10);
 	NVGcolor colorOutline = nvgLerpRGBA(color, nvgRGBf(0.0, 0.0, 0.0), 0.5);
 
 	// Wire
 	if (opacity > 0.0) {
 		nvgSave(vg);
-		nvgGlobalAlpha(vg, powf(opacity, 1.5));
+		// This power scaling looks more linear than actual linear scaling
+		nvgGlobalAlpha(vg, std::pow(opacity, 1.5));
 
 		float dist = pos1.minus(pos2).norm();
 		math::Vec slump;
@@ -53,7 +54,7 @@ static void drawWire(NVGcontext *vg, math::Vec pos1, math::Vec pos2, NVGcolor co
 		nvgMoveTo(vg, pos1.x, pos1.y);
 		nvgQuadTo(vg, pos4.x, pos4.y, pos2.x, pos2.y);
 		nvgStrokeColor(vg, colorShadow);
-		nvgStrokeWidth(vg, 5);
+		nvgStrokeWidth(vg, width);
 		nvgStroke(vg);
 
 		// Wire outline
@@ -61,12 +62,12 @@ static void drawWire(NVGcontext *vg, math::Vec pos1, math::Vec pos2, NVGcolor co
 		nvgMoveTo(vg, pos1.x, pos1.y);
 		nvgQuadTo(vg, pos3.x, pos3.y, pos2.x, pos2.y);
 		nvgStrokeColor(vg, colorOutline);
-		nvgStrokeWidth(vg, 5);
+		nvgStrokeWidth(vg, width);
 		nvgStroke(vg);
 
 		// Wire solid
 		nvgStrokeColor(vg, color);
-		nvgStrokeWidth(vg, 3);
+		nvgStrokeWidth(vg, width - 2);
 		nvgStroke(vg);
 
 		nvgRestore(vg);
@@ -178,9 +179,17 @@ void WireWidget::draw(NVGcontext *vg) {
 			opacity = 1.0;
 	}
 
+	float width = 5;
+	if (wire && wire->outputModule) {
+		Output *output = &wire->outputModule->outputs[wire->outputId];
+		if (output->numChannels != 1) {
+			width = 8;
+		}
+	}
+
 	math::Vec outputPos = getOutputPos();
 	math::Vec inputPos = getInputPos();
-	drawWire(vg, outputPos, inputPos, color, tension, opacity);
+	drawWire(vg, outputPos, inputPos, color, width, tension, opacity);
 }
 
 void WireWidget::drawPlugs(NVGcontext *vg) {
diff --git a/src/engine/Wire.cpp b/src/engine/Wire.cpp
index 45d735d6..9dd9bb62 100644
--- a/src/engine/Wire.cpp
+++ b/src/engine/Wire.cpp
@@ -5,9 +5,14 @@ namespace rack {
 
 
 void Wire::step() {
-	// Copy output to input
-	float value = outputModule->outputs[outputId].value;
-	inputModule->inputs[inputId].value = value;
+	Output *output = &outputModule->outputs[outputId];
+	Input *input = &inputModule->inputs[inputId];
+	// Match number of polyphonic channels to output port
+	input->numChannels = output->numChannels;
+	// Copy values from output to input
+	for (int i = 0; i < output->numChannels; i++) {
+		input->values[i] = output->values[i];
+	}
 }