From a27db526afd51f3b2c1caa9751f83a08a7944b91 Mon Sep 17 00:00:00 2001
From: Alvin Wong <alvinhochun@gmail.com>
Date: Mon, 3 May 2021 16:53:45 +0800
Subject: [PATCH] Remove the scroll indicator when scrolling menu

---
 source/Core/Drivers/OLED.cpp | 30 ++++++++++++++++++++++++++++++
 source/Core/Drivers/OLED.hpp |  1 +
 source/Core/Src/gui.cpp      |  3 ++-
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/source/Core/Drivers/OLED.cpp b/source/Core/Drivers/OLED.cpp
index 65dce02b..fc8ef266 100644
--- a/source/Core/Drivers/OLED.cpp
+++ b/source/Core/Drivers/OLED.cpp
@@ -211,6 +211,36 @@ void OLED::drawScrollIndicator(uint8_t y, uint8_t height) {
   fillArea(OLED_WIDTH - 1, 8, 1, 8, column.strips[1]);
 }
 
+/**
+ * Masks (removes) the scrolling indicator, i.e. clears the rightmost column
+ * on the screen. This operates directly on the OLED graphics RAM, as this
+ * is intended to be used before calling `OLED::transitionScrollDown()`.
+ */
+void OLED::maskScrollIndicatorOnOLED() {
+  // The right-most column depends on the screen rotation, so just take
+  // it from the screen buffer which is updated by `OLED::setRotation`.
+  uint8_t rightmostColumn = screenBuffer[7];
+  uint8_t maskCommands[]  = {
+      // Set column address:
+      //  A[6:0] - Column start address = rightmost column
+      //  B[6:0] - Column end address = rightmost column
+      0x80,
+      0x21, // cmd
+      0x80,
+      rightmostColumn, // A
+      0x80,
+      rightmostColumn, // B
+
+      // Start of data
+      0x40,
+
+      // Clears two 8px strips
+      0x00,
+      0x00,
+  };
+  FRToSI2C::Transmit(DEVICEADDR_OLED, maskCommands, sizeof(maskCommands));
+}
+
 /**
  * Plays a transition animation between two framebuffers.
  * @param forwardNavigation Direction of the navigation animation.
diff --git a/source/Core/Drivers/OLED.hpp b/source/Core/Drivers/OLED.hpp
index 7d88ac96..c108dcf7 100644
--- a/source/Core/Drivers/OLED.hpp
+++ b/source/Core/Drivers/OLED.hpp
@@ -79,6 +79,7 @@ public:
   static void drawFilledRect(uint8_t x0, uint8_t y0, uint8_t x1, uint8_t y1, bool clear);
   static void drawHeatSymbol(uint8_t state);
   static void drawScrollIndicator(uint8_t p, uint8_t h); // Draws a scrolling position indicator
+  static void maskScrollIndicatorOnOLED();
   static void transitionSecondaryFramebuffer(bool forwardNavigation);
   static void useSecondaryFramebuffer(bool useSecondary);
   static void transitionScrollDown();
diff --git a/source/Core/Src/gui.cpp b/source/Core/Src/gui.cpp
index 15a6a82e..63eb711f 100644
--- a/source/Core/Src/gui.cpp
+++ b/source/Core/Src/gui.cpp
@@ -1086,7 +1086,7 @@ void gui_Menu(const menuitem *menu) {
       uint8_t position        = OLED_HEIGHT * currentScreen / scrollContentSize;
       if (lastValue)
         scrollBlink = !scrollBlink;
-      if (!lastValue || !scrollBlink)
+      if ((!lastValue || !scrollBlink) && !scrollingDown)
         OLED::drawScrollIndicator(position, indicatorHeight);
     } else {
       // Draw description
@@ -1096,6 +1096,7 @@ void gui_Menu(const menuitem *menu) {
 
     if (lcdRefresh) {
       if (scrollingDown) {
+        OLED::maskScrollIndicatorOnOLED();
         OLED::transitionScrollDown();
         scrollingDown = false;
         animOpenState = false;