From 3c5e5b46a36b3fd44a0c714926d12411176d5685 Mon Sep 17 00:00:00 2001
From: Christian Colglazier <christian@cacolglazier.com>
Date: Mon, 1 Nov 2021 21:08:10 -0400
Subject: [PATCH] Basic VCA

---
 src/droplets/vca_droplet.cpp | 50 ++++++++++++++++++++++++++++++++
 src/droplets/vca_droplet.h   | 56 ++++++++++++++++++++++++++++++++++++
 src/main.cpp                 |  3 ++
 src/main.h                   |  1 +
 src/menu.cpp                 |  1 +
 src/menu_item.h              |  2 +-
 6 files changed, 112 insertions(+), 1 deletion(-)
 create mode 100644 src/droplets/vca_droplet.cpp
 create mode 100644 src/droplets/vca_droplet.h

diff --git a/src/droplets/vca_droplet.cpp b/src/droplets/vca_droplet.cpp
new file mode 100644
index 0000000..9d7af64
--- /dev/null
+++ b/src/droplets/vca_droplet.cpp
@@ -0,0 +1,50 @@
+#include "vca_droplet.h"
+
+VCADroplet::VCADroplet(DaisyPatch* m_patch,
+		       DropletState m_state) :
+  Droplet(m_patch,
+	  m_state) {
+  switch (GetState()) {
+  default:
+  case DropletState::kFull:
+    vca[0].Init(Patch()->controls[Patch()->CTRL_1],
+		0.0, 1.0f, Parameter::LINEAR);
+    vca[1].Init(Patch()->controls[Patch()->CTRL_2],
+		0.0, 1.0f, Parameter::LINEAR);
+    vca[2].Init(Patch()->controls[Patch()->CTRL_3],
+		0.0, 1.0f, Parameter::LINEAR);
+    vca[3].Init(Patch()->controls[Patch()->CTRL_4],
+		0.0, 1.0f, Parameter::LINEAR);
+    break;
+  case DropletState::kLeft:
+    vca[0].Init(Patch()->controls[Patch()->CTRL_1],
+		0.0, 1.0f, Parameter::LINEAR);
+    vca[1].Init(Patch()->controls[Patch()->CTRL_2],
+		0.0, 1.0f, Parameter::LINEAR);
+    break;
+  case DropletState::kRight:
+    vca[2].Init(Patch()->controls[Patch()->CTRL_3],
+		0.0, 1.0f, Parameter::LINEAR);
+    vca[3].Init(Patch()->controls[Patch()->CTRL_3],
+		0.0, 1.0f, Parameter::LINEAR);
+    break;
+  }
+}
+
+VCADroplet::~VCADroplet() {}
+
+void VCADroplet::Control() {}
+
+void VCADroplet::Process(AudioHandle::InputBuffer in, AudioHandle::OutputBuffer out, size_t size) {
+  Patch()->ProcessAnalogControls();
+  
+  for (size_t i = 0; i < size; i++) {
+    for (size_t chn = GetChannelMin(); chn < GetChannelMax(); chn++) {
+      out[chn][i] = in[chn][i] * vca[chn].Process();
+    }
+  }
+}
+
+void VCADroplet::Draw() {
+  DrawName("VCA");
+}
diff --git a/src/droplets/vca_droplet.h b/src/droplets/vca_droplet.h
new file mode 100644
index 0000000..a00ce64
--- /dev/null
+++ b/src/droplets/vca_droplet.h
@@ -0,0 +1,56 @@
+#pragma once
+
+#ifndef CASCADE_DROPLETS_VCA_DROPLET_H_
+#define CASCADE_DROPLETS_VCA_DROPLET_H_
+
+#include "daisysp.h"
+#include "daisy_patch.h"
+
+#include "droplet.h"
+#include "../util.h"
+
+using namespace daisy;
+using namespace daisysp;
+
+class VCADroplet: public Droplet {
+private:
+  Parameter vca[4];
+
+public:
+  /*
+   * Constructor for voltage amplifier droplet.
+   *
+   * @param m_patch pointer to patch
+   * @param m_state droplet position
+   */
+  VCADroplet(DaisyPatch* m_patch,
+	     DropletState m_state);
+  
+  /*
+   * Destructor for vco droplet.
+   */
+  ~VCADroplet();
+
+  /*
+   * Processes user controls and inputs.
+   */
+  void Control();
+
+  /*
+   * Processes audio input and outputs.
+   *
+   * @param in the audio inputs for the patch
+   * @param out the audio outputs for the patch
+   * @param size the number of inputs and outputs
+   */
+  void Process(AudioHandle::InputBuffer in,
+	       AudioHandle::OutputBuffer out,
+	       size_t size);
+
+  /*
+   * Processes information to be shown on the display. 
+   */
+  void Draw();
+};
+
+#endif // CASCADE_DROPLETS_VCA_DROPLET_H_
diff --git a/src/main.cpp b/src/main.cpp
index 05d2295..31d3ea4 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -114,6 +114,9 @@ static void AudioThrough(AudioHandle::InputBuffer in,
 
 Droplet* GetDroplet(DropletState state) {
   switch(selected_menu->GetState()) {
+  case MenuState::kVCA:
+    return new VCADroplet(&patch,
+			  state);
   case MenuState::kVCO:
     return new VCODroplet(&patch,
 			  state,
diff --git a/src/main.h b/src/main.h
index bb8052f..2055715 100644
--- a/src/main.h
+++ b/src/main.h
@@ -13,6 +13,7 @@
 #include "droplets/droplet.h"
 #include "droplets/droplet_manager.h"
 #include "droplets/noise_droplet.h"
+#include "droplets/vca_droplet.h"
 #include "droplets/vco_droplet.h"
 
 DaisyPatch patch;
diff --git a/src/menu.cpp b/src/menu.cpp
index ffc75a8..dd87dac 100644
--- a/src/menu.cpp
+++ b/src/menu.cpp
@@ -10,6 +10,7 @@ Menu::Menu(DaisyPatch* m_patch,
   head = new MenuItem(MenuState::kSplit, "Split");
   head->AddItemEnd(new MenuItem(MenuState::kChange, ""));
   head->AddItemEnd(new MenuItem(MenuState::kVCO, "VCO"));
+  head->AddItemEnd(new MenuItem(MenuState::kVCA, "VCA"));
   head->AddItemEnd(new MenuItem(MenuState::kNoise, "Noise"));
   
   selected = head;
diff --git a/src/menu_item.h b/src/menu_item.h
index eb95ada..c0519b4 100644
--- a/src/menu_item.h
+++ b/src/menu_item.h
@@ -5,7 +5,7 @@
 
 #include <string>
 
-enum class MenuState {kSplit, kChange, kVCO, kNoise};
+enum class MenuState {kSplit, kChange, kVCA, kVCO, kNoise};
 
 class MenuItem {
  private: