From d69293342d280cee9cee9ac3a1db090cfd7ea51d Mon Sep 17 00:00:00 2001
From: Patrick Horlebein <patrick@ilovepatrick.de>
Date: Sat, 25 Apr 2020 11:43:14 +0200
Subject: [PATCH] Add secondary framebuffer, instead of allocating on stack

---
 workspace/TS100/Core/Inc/OLED.hpp |  6 ++++--
 workspace/TS100/Core/Src/OLED.cpp | 20 ++++++++++++++------
 workspace/TS100/Core/Src/gui.cpp  | 14 ++++++--------
 3 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/workspace/TS100/Core/Inc/OLED.hpp b/workspace/TS100/Core/Inc/OLED.hpp
index e6077494..6fffb1fe 100644
--- a/workspace/TS100/Core/Inc/OLED.hpp
+++ b/workspace/TS100/Core/Inc/OLED.hpp
@@ -101,10 +101,11 @@ public:
 			bool clear);
 	static void drawHeatSymbol(uint8_t state);
 	static void drawScrollIndicator(uint8_t p, uint8_t h); // Draws a scrolling position indicator
-	static void transitionToContents(uint8_t *framebuffer, bool forwardNavigation);
-	static void set_framebuffer(uint8_t *buffer);
+	static void transitionSecondaryFramebuffer(bool forwardNavigation);
+    static void useSecondaryFramebuffer(bool useSecondary);
 private:
 	static void drawChar(char c); // Draw a character to a specific location
+    static void setFramebuffer(uint8_t *buffer);
 	static const uint8_t* currentFont;// Pointer to the current font used for rendering to the buffer
 	static uint8_t* firstStripPtr; // Pointers to the strips to allow for buffer having extra content
 	static uint8_t* secondStripPtr;	//Pointers to the strips
@@ -114,6 +115,7 @@ private:
 	static int16_t cursor_x, cursor_y;
 	static uint8_t displayOffset;
 	static uint8_t screenBuffer[16 + (OLED_WIDTH * 2) + 10];  // The data buffer
+    static uint8_t secondFrameBuffer[OLED_WIDTH * 2];
 };
 
 #endif /* OLED_HPP_ */
diff --git a/workspace/TS100/Core/Src/OLED.cpp b/workspace/TS100/Core/Src/OLED.cpp
index 5893556c..91d47149 100644
--- a/workspace/TS100/Core/Src/OLED.cpp
+++ b/workspace/TS100/Core/Src/OLED.cpp
@@ -24,6 +24,7 @@ uint8_t OLED::fontWidth, OLED::fontHeight;
 int16_t OLED::cursor_x, OLED::cursor_y;
 uint8_t OLED::displayOffset;
 uint8_t OLED::screenBuffer[16 + (OLED_WIDTH * 2) + 10];  // The data buffer
+uint8_t OLED::secondFrameBuffer[OLED_WIDTH * 2];
 
 /*Setup params for the OLED screen*/
 /*http://www.displayfuture.com/Display/datasheet/controller/SSD1307.pdf*/
@@ -93,7 +94,7 @@ void OLED::initialize() {
 			sizeof(OLED_Setup_Array));
 }
 
-void OLED::set_framebuffer(uint8_t *buffer) {
+void OLED::setFramebuffer(uint8_t *buffer) {
 	if (buffer == NULL) {
 		firstStripPtr = &screenBuffer[FRAMEBUFFER_START];
 		secondStripPtr = &screenBuffer[FRAMEBUFFER_START + OLED_WIDTH];
@@ -146,15 +147,14 @@ void OLED::drawScrollIndicator(uint8_t y, uint8_t height) {
 
 /**
  * Plays a transition animation between two framebuffers.
- * @param framebuffer Second framebuffer to use for animation.
- * @param forward Direction of the navigation animation.
+ * @param forwardNavigation Direction of the navigation animation.
  *
  * If forward is true, this displays a forward navigation to the second framebuffer contents.
  * Otherwise a rewinding navigation animation is shown to the second framebuffer contents.
  */
-void OLED::transitionToContents(uint8_t *framebuffer, bool forwardNavigation) {
-	uint8_t *firstBackStripPtr = &framebuffer[0];
-	uint8_t *secondBackStripPtr = &framebuffer[OLED_WIDTH];
+void OLED::transitionSecondaryFramebuffer(bool forwardNavigation) {
+	uint8_t *firstBackStripPtr = &secondFrameBuffer[0];
+	uint8_t *secondBackStripPtr = &secondFrameBuffer[OLED_WIDTH];
 
 	uint32_t totalDuration = 50; // 500ms
 	uint32_t duration = 0;
@@ -193,6 +193,14 @@ void OLED::transitionToContents(uint8_t *framebuffer, bool forwardNavigation) {
 	}
 }
 
+void OLED::useSecondaryFramebuffer(bool useSecondary) {
+    if (useSecondary) {
+        setFramebuffer(secondFrameBuffer);
+    } else {
+        setFramebuffer(NULL);
+    }
+}
+
 void OLED::setRotation(bool leftHanded) {
 #ifdef MODEL_TS80
 	leftHanded = !leftHanded;
diff --git a/workspace/TS100/Core/Src/gui.cpp b/workspace/TS100/Core/Src/gui.cpp
index 019ed102..a38aae4d 100644
--- a/workspace/TS100/Core/Src/gui.cpp
+++ b/workspace/TS100/Core/Src/gui.cpp
@@ -840,14 +840,13 @@ void gui_Menu(const menuitem *menu) {
 		// Then we play a transition from the current primary
 		// framebuffer to the new buffer.
 		// The extra buffer is discarded at the end of the transition.
-		uint8_t secondaryFrameBuffer[OLED_WIDTH * 2];
-		OLED::set_framebuffer(secondaryFrameBuffer);
+		OLED::useSecondaryFramebuffer(true);
 		OLED::setFont(0);
 		OLED::setCursor(0, 0);
 		OLED::clearScreen();
 		menu[currentScreen].draw.func();
-		OLED::set_framebuffer(NULL);
-		OLED::transitionToContents(secondaryFrameBuffer, true);
+		OLED::useSecondaryFramebuffer(false);
+		OLED::transitionSecondaryFramebuffer(true);
 	}
 
 	while ((menu[currentScreen].draw.func != NULL) && earlyExit == false) {
@@ -905,14 +904,13 @@ void gui_Menu(const menuitem *menu) {
 					menu[currentScreen].incrementHandler.func();
 
 					if (enterGUIMenu) {
-						uint8_t secondaryFrameBuffer[OLED_WIDTH * 2];
-						OLED::set_framebuffer(secondaryFrameBuffer);
+						OLED::useSecondaryFramebuffer(true);
 						OLED::setFont(0);
 						OLED::setCursor(0, 0);
 						OLED::clearScreen();
 						menu[currentScreen].draw.func();
-						OLED::set_framebuffer(NULL);
-						OLED::transitionToContents(secondaryFrameBuffer, false);
+						OLED::useSecondaryFramebuffer(false);
+						OLED::transitionSecondaryFramebuffer(false);
 					}
 					enterGUIMenu = true;
 				} else {