From 8ebc5e933a9725cad6577e3c8a09998b6393445b Mon Sep 17 00:00:00 2001
From: Emil Muratov <gpm@hotplug.ru>
Date: Sat, 22 May 2021 01:57:54 +0300
Subject: [PATCH] clearScreen() now wipes only color data for current buffer

Signed-off-by: Emil Muratov <gpm@hotplug.ru>
---
 ESP32-HUB75-MatrixPanel-I2S-DMA.cpp | 12 ------------
 ESP32-HUB75-MatrixPanel-I2S-DMA.h   | 22 +++++++++++++++++-----
 ESP32-VirtualMatrixPanel-I2S-DMA.h  |  2 +-
 3 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/ESP32-HUB75-MatrixPanel-I2S-DMA.cpp b/ESP32-HUB75-MatrixPanel-I2S-DMA.cpp
index f88d18c..9aeecc7 100644
--- a/ESP32-HUB75-MatrixPanel-I2S-DMA.cpp
+++ b/ESP32-HUB75-MatrixPanel-I2S-DMA.cpp
@@ -588,18 +588,6 @@ void MatrixPanel_I2S_DMA::updateMatrixDMABuffer(uint8_t red, uint8_t green, uint
   } // colour depth loop (8)
 } // updateMatrixDMABuffer (full frame paint)
 
-/**
- * clear screen to black and reset all service bits
- */
-void MatrixPanel_I2S_DMA::clearScreen(){
-  clearFrameBuffer();
-  brtCtrlOE(brightness);
-  if (m_cfg.double_buff){
-    clearFrameBuffer(1); 
-    brtCtrlOE(brightness, 1);
-  }
-}
-
 /**
  * @brief - clears and reinitializes color/control data in DMA buffs
  * When allocated, DMA buffs might be dirtry, so we need to blank it and initialize ABCDE,LAT,OE control bits.
diff --git a/ESP32-HUB75-MatrixPanel-I2S-DMA.h b/ESP32-HUB75-MatrixPanel-I2S-DMA.h
index 9df1390..cd11b80 100644
--- a/ESP32-HUB75-MatrixPanel-I2S-DMA.h
+++ b/ESP32-HUB75-MatrixPanel-I2S-DMA.h
@@ -370,7 +370,7 @@ class MatrixPanel_I2S_DMA {
         
 
       // Flush the DMA buffers prior to configuring DMA - Avoid visual artefacts on boot.
-      clearScreen(); // Must fill the DMA buffer with the initial output bit sequence or the panel will display garbage
+      resetbuffers(); // Must fill the DMA buffer with the initial output bit sequence or the panel will display garbage
 
       // Setup the ESP32 DMA Engine. Sprite_TM built this stuff.
       configureDMA(m_cfg); //DMA and I2S configuration and setup
@@ -398,10 +398,10 @@ class MatrixPanel_I2S_DMA {
     virtual void fillScreen(uint16_t color);                        // overwrite adafruit implementation
 
     /**
-     * clears DMA buffers and reinitializes control bits
-     * to just clear the screen to black fillScreen(0) works faster
+     * A wrapper to fill the entire Screen with black
+     * if double buffering is used, than only back buffer is cleared
      */
-    void clearScreen();
+    inline void clearScreen(){ updateMatrixDMABuffer(0,0,0); };
 
 #ifndef NO_FAST_FUNCTIONS
     /**
@@ -547,7 +547,7 @@ class MatrixPanel_I2S_DMA {
      * Stop the ESP32 DMA Engine. Screen will forever be black until next ESP reboot.
      */
     void stopDMAoutput() {  
-        clearScreen();
+        resetbuffers();
         i2s_parallel_stop_dma(I2S_NUM_1);
     } 
     
@@ -573,6 +573,18 @@ class MatrixPanel_I2S_DMA {
     /* Update the entire DMA buffer (aka. The RGB Panel) a certain colour (wipe the screen basically) */
     void updateMatrixDMABuffer(uint8_t red, uint8_t green, uint8_t blue);       
 
+    /**
+     * wipes DMA buffer(s) and reset all color/service bits
+     */
+    inline void resetbuffers(){
+      clearFrameBuffer();
+      brtCtrlOE(brightness);
+      if (m_cfg.double_buff){
+        clearFrameBuffer(1); 
+        brtCtrlOE(brightness, 1);
+      }
+    }
+
 
 #ifndef NO_FAST_FUNCTIONS
     /**
diff --git a/ESP32-VirtualMatrixPanel-I2S-DMA.h b/ESP32-VirtualMatrixPanel-I2S-DMA.h
index 5dee0b4..eba4e95 100644
--- a/ESP32-VirtualMatrixPanel-I2S-DMA.h
+++ b/ESP32-VirtualMatrixPanel-I2S-DMA.h
@@ -70,7 +70,7 @@ class VirtualMatrixPanel
     virtual void drawPixel(int16_t x, int16_t y, uint16_t color);
     virtual void fillScreen(uint16_t color); // overwrite adafruit implementation
     void clearScreen() {
-      fillScreen(0);
+      display->clearScreen();
     }
     //void drawPixelRGB565(int16_t x, int16_t y, uint16_t color);
     void drawPixelRGB888(int16_t x, int16_t y, uint8_t r, uint8_t g, uint8_t b);