From 8106e4ae70809e1a1e6c69c1b81494547dbb1a27 Mon Sep 17 00:00:00 2001
From: Christian Colglazier <christian@cacolglazier.com>
Date: Wed, 23 Sep 2020 20:09:12 -0400
Subject: [PATCH] Sprite shifting support

---
 src/droplets/droplet.cpp     |  7 ++++---
 src/droplets/droplet.h       |  1 +
 src/droplets/vco_droplet.cpp | 15 +++++++++------
 src/graphics/sprite.cpp      | 36 +++++++++++++++++++++++++++++++++---
 src/graphics/sprite.h        |  9 +++++++++
 5 files changed, 56 insertions(+), 12 deletions(-)

diff --git a/src/droplets/droplet.cpp b/src/droplets/droplet.cpp
index 3bfbda4..831136f 100644
--- a/src/droplets/droplet.cpp
+++ b/src/droplets/droplet.cpp
@@ -57,9 +57,6 @@ void Droplet::AnimationInc() {
     count = 0;
   }
   count++;
-  //animation_count = animation_count % animation_rate;
-  WriteCenteredString(*patch, (screen_min + screen_max) / 2, 40,
-		      Font_6x8, std::to_string(animation_count));
 }
 
 void Droplet::SetAnimationRate(int rate) {
@@ -69,3 +66,7 @@ void Droplet::SetAnimationRate(int rate) {
 int Droplet::GetAnimationCount() {
   return animation_count;
 }
+
+bool Droplet::NeedUpdate() {
+  return count % animation_rate == 0;
+}
diff --git a/src/droplets/droplet.h b/src/droplets/droplet.h
index 20fd503..9d730e7 100644
--- a/src/droplets/droplet.h
+++ b/src/droplets/droplet.h
@@ -43,6 +43,7 @@ public:
   void AnimationInc();
   void SetAnimationRate(int);
   int GetAnimationCount();
+  bool NeedUpdate();
 };
 
 #endif // CASCADE_DROPLETS_DROPLET_H_
diff --git a/src/droplets/vco_droplet.cpp b/src/droplets/vco_droplet.cpp
index 1226a5f..7b95a5d 100644
--- a/src/droplets/vco_droplet.cpp
+++ b/src/droplets/vco_droplet.cpp
@@ -16,6 +16,12 @@ VCODroplet::VCODroplet(DaisyPatch* m_patch,
 		num_waves, Parameter::LINEAR);
   ampctrl.Init(Patch()->controls[Patch()->CTRL_4], 0.0,
 	       0.5f, Parameter::LINEAR);
+
+  wave->SetBlank();
+  for (int i = 0; i < sine_width; i++) {
+    int pixel = (int) round(std::sin(2*pi*((double)(i%sine_width)/sine_width)) * (GetTitleHeight()/2) + GetTitleHeight()/2);
+    wave->SetPixel(i, pixel, true);
+  }
 }
 
 VCODroplet::~VCODroplet() {
@@ -49,15 +55,12 @@ void VCODroplet::Process(float** in, float** out, size_t size) {
 }
 
 void VCODroplet::Draw() {
-  wave->SetBlank();
-  for (int i = 0; i < sine_width; i++) {
-    int pixel = (int) round(std::sin(2*pi*((double)(i + GetAnimationCount()%sine_width)/sine_width)) * (GetTitleHeight()/2) + GetTitleHeight()/2);
-    wave->SetPixel(i, pixel, true);
-  }
-  
   WriteString(*Patch(), 0, 54, Font_6x8,
 	      WaveToString(wavectrl.Process()));
   wave->DrawTile(*Patch(), GetScreenMin(), 0, GetScreenMax(), GetTitleHeight());
+  if(NeedUpdate()) {
+    wave->AdjustXShift(1);
+  }
   DrawName("VCO");
   AnimationInc();
 }
diff --git a/src/graphics/sprite.cpp b/src/graphics/sprite.cpp
index 8f3b6ef..b31ffa3 100644
--- a/src/graphics/sprite.cpp
+++ b/src/graphics/sprite.cpp
@@ -36,7 +36,9 @@ int Sprite::GetWidth() {
 void Sprite::Draw(DaisyPatch patch, int x, int y) {
   for (int w = 0; w < width; w++) {
     for (int h = 0; h < height; h++) {
-      patch.display.DrawPixel(x+w, y+h, sprite[w][h]);
+      patch.display.DrawPixel(x+w, y+h,
+			      sprite[GetShiftArrayX(w)]
+			      [GetShiftArrayY(h)]);
     }
   }
 }
@@ -52,8 +54,8 @@ void Sprite::DrawTile(DaisyPatch patch,
   int y_max = std::max(y1, y2);
   for (int w = x_min; w < x_max; w++) {
     for (int h = y_min; h < y_max; h++) {
-      patch.display.DrawPixel(w, h, sprite[(w-x_min) % width]
-			      [(h-y_min) % height]);
+      patch.display.DrawPixel(w, h, sprite[GetShiftArrayX((w-x_min) % width)]
+			      [GetShiftArrayY((h-y_min+y_shift) % height)]);
     }
   }
 }
@@ -69,3 +71,31 @@ void Sprite::SetBlank() {
     }  
   }
 }
+
+void Sprite::SetXShift(int x) {
+  x_shift = x;
+}
+
+void Sprite::SetYShift(int y) {
+  y_shift = y;
+}
+
+void Sprite::AdjustXShift(int x) {
+  x_shift -= x;
+}
+
+void Sprite::AdjustYShift(int y) {
+  y_shift += y;
+}
+
+int Sprite::GetShiftArray(int pos, int shift, int array_size) {
+  return (array_size + ((pos + shift) % array_size)) % array_size;
+}
+
+int Sprite::GetShiftArrayX(int pos) {
+  return GetShiftArray(pos, x_shift, width);
+}
+
+int Sprite::GetShiftArrayY(int pos) {
+  return GetShiftArray(pos, y_shift, height);
+}
diff --git a/src/graphics/sprite.h b/src/graphics/sprite.h
index bd1699f..38523f3 100644
--- a/src/graphics/sprite.h
+++ b/src/graphics/sprite.h
@@ -11,6 +11,11 @@ class Sprite {
  private:
   int width, height;
   bool** sprite;
+  int x_shift = 0;
+  int y_shift = 0;
+  int GetShiftArray(int, int, int);
+  int GetShiftArrayX(int);
+  int GetShiftArrayY(int);
  public:
   Sprite(int, int);
   ~Sprite();
@@ -21,6 +26,10 @@ class Sprite {
   void Draw(DaisyPatch, int, int);
   void DrawTile(DaisyPatch, int, int, int, int);
   void SetBlank();
+  void SetXShift(int);
+  void SetYShift(int);
+  void AdjustXShift(int);
+  void AdjustYShift(int);
 };
 
 #endif // CASCADE_GRAPHICS_SPRITE_H_