Fix Sprite 1bpp scroll bug

Sprite scroll function fixed for 1bpp
readPixelValue() updated

Performance of circle drawing functions improved.

Version raised to 2.2.0

Extensions/Sprite.cpp

@@ -681,10 +681,22 @@ void TFT_eSprite::pushSprite(int32_t x, int32_t y, uint16_t transp)
 ** Function name:           readPixelValue
 ** Description:             Read the color map index of a pixel at defined coordinates
 *************************************************************************************x*/
-uint8_t TFT_eSprite::readPixelValue(int32_t x, int32_t y)
+uint16_t TFT_eSprite::readPixelValue(int32_t x, int32_t y)
 {
   if ((x < 0) || (x >= _iwidth) || (y < 0) || (y >= _iheight) || !_created) return 0xFF;
 
+  if (_bpp == 16)
+  {
+    // Return the pixel colour
+    return readPixel(x, y);
+  }
+
+  if (_bpp == 8)
+  {
+    // Return the pixel byte value
+    return _img8[x + y * _iwidth];
+  }
+
   if (_bpp == 4)
   {
     if ((x & 0x01) == 0)
@@ -692,7 +704,31 @@ uint8_t TFT_eSprite::readPixelValue(int32_t x, int32_t y)
     else
       return _img4[((x+y*_iwidth)>>1)] & 0x0F; // odd index = bits 3 .. 0.
   }
-  return readPixel(x, y);
+
+  if (_bpp == 1)
+  {
+    if (_rotation == 1)
+    {
+      uint16_t tx = x;
+      x = _dwidth - y - 1;
+      y = tx;
+    }
+    else if (_rotation == 2)
+    {
+      x = _dwidth - x - 1;
+      y = _dheight - y - 1;
+    }
+    else if (_rotation == 3)
+    {
+      uint16_t tx = x;
+      x = y;
+      y = _dheight - tx - 1;
+    }
+    // Return 1 or 0
+    return (_img8[(x + y * _bitwidth)>>3] >> (7-(x & 0x7))) & 0x01;
+  }
+
+  return 0;
 }
 
 /***************************************************************************************
@@ -1227,8 +1263,8 @@ void TFT_eSprite::scroll(int16_t dx, int16_t dy)
     { // move pixels one by one
       for (uint16_t xp = 0; xp < w; xp++)
       {
-        if (dx <= 0) drawPixel(tx + xp, ty, readPixel(fx + xp, fy));
-        if (dx >  0) drawPixel(tx - xp, ty, readPixel(fx - xp, fy));
+        if (dx <= 0) drawPixel(tx + xp, ty, readPixelValue(fx + xp, fy));
+        if (dx >  0) drawPixel(tx - xp, ty, readPixelValue(fx - xp, fy));
       }
       if (dy <= 0)  { ty++; fy++; }
       else  { ty--; fy--; }

Extensions/Sprite.h

@@ -110,8 +110,9 @@ class TFT_eSprite : public TFT_eSPI {
            // Read the colour of a pixel at x,y and return value in 565 format 
   uint16_t readPixel(int32_t x0, int32_t y0);
 
-           // return the color map index of the pixel at x,y (used when scrolling)
-  uint8_t  readPixelValue(int32_t x, int32_t y);
+           // return the numerical value of the pixel at x,y (used when scrolling)
+           // 16bpp = colour, 8bpp = byte, 4bpp = colour index, 1bpp = 1 or 0
+  uint16_t readPixelValue(int32_t x, int32_t y);
 
            // Write an image (colour bitmap) to the sprite.  Not implemented for _bpp == 4.
   void     pushImage(int32_t x0, int32_t y0, int32_t w, int32_t h, uint16_t *data);

TFT_eSPI.cpp

@@ -1591,7 +1591,7 @@ void  TFT_eSPI::readRectRGB(int32_t x0, int32_t y0, int32_t w, int32_t h, uint8_
 // Optimised midpoint circle algorithm
 void TFT_eSPI::drawCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
 {
-  int32_t  x  = 0;
+  int32_t  x  = 1;
   int32_t  dx = 1;
   int32_t  dy = r+r;
   int32_t  p  = -(r>>1);
@@ -1617,19 +1617,19 @@ void TFT_eSPI::drawCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
     dx+=2;
     p+=dx;
 
-    x++;
-
     // These are ordered to minimise coordinate changes in x or y
     // drawPixel can then send fewer bounding box commands
     drawPixel(x0 + x, y0 + r, color);
     drawPixel(x0 - x, y0 + r, color);
     drawPixel(x0 - x, y0 - r, color);
     drawPixel(x0 + x, y0 - r, color);
-
-    drawPixel(x0 + r, y0 + x, color);
-    drawPixel(x0 - r, y0 + x, color);
-    drawPixel(x0 - r, y0 - x, color);
-    drawPixel(x0 + r, y0 - x, color);
+    if (r != x) {
+      drawPixel(x0 + r, y0 + x, color);
+      drawPixel(x0 - r, y0 + x, color);
+      drawPixel(x0 - r, y0 - x, color);
+      drawPixel(x0 + r, y0 - x, color);
+    }
+    x++;
   }
 
   inTransaction = false;
@@ -1639,7 +1639,7 @@ void TFT_eSPI::drawCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
 
 /***************************************************************************************
 ** Function name:           drawCircleHelper
-** Description:             Support function for circle drawing
+** Description:             Support function for drawRoundRect()
 ***************************************************************************************/
 void TFT_eSPI::drawCircleHelper( int32_t x0, int32_t y0, int32_t r, uint8_t cornername, uint32_t color)
 {
@@ -1682,21 +1682,26 @@ void TFT_eSPI::drawCircleHelper( int32_t x0, int32_t y0, int32_t r, uint8_t corn
 ** Description:             draw a filled circle
 ***************************************************************************************/
 // Optimised midpoint circle algorithm, changed to horizontal lines (faster in sprites)
+// Improved algorithm avoids repetition of lines
 void TFT_eSPI::fillCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
 {
-  int32_t  x  = 0;
+  int32_t  x  = 1;
   int32_t  dx = 1;
   int32_t  dy = r+r;
+  int32_t  ly = y0;
   int32_t  p  = -(r>>1);
+  int32_t  xo = 0;
 
   //begin_tft_write();          // Sprite class can use this function, avoiding begin_tft_write()
   inTransaction = true;
 
   drawFastHLine(x0 - r, y0, dy+1, color);
 
-  while(x<r){
+  while(xo<r){
 
     if(p>=0) {
+      drawFastHLine(x0 - xo, y0 + r, 2 * xo+1, color);
+      drawFastHLine(x0 - xo, y0 - r, 2 * xo+1, color);
       dy-=2;
       p-=dy;
       r--;
@@ -1704,13 +1709,11 @@ void TFT_eSPI::fillCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
 
     dx+=2;
     p+=dx;
-
-    x++;
+    xo = x;
 
     drawFastHLine(x0 - r, y0 + x, 2 * r+1, color);
     drawFastHLine(x0 - r, y0 - x, 2 * r+1, color);
-    drawFastHLine(x0 - x, y0 + r, 2 * x+1, color);
-    drawFastHLine(x0 - x, y0 - r, 2 * x+1, color);
+    x++;
   }
 
   inTransaction = false;
@@ -1720,7 +1723,7 @@ void TFT_eSPI::fillCircle(int32_t x0, int32_t y0, int32_t r, uint32_t color)
 
 /***************************************************************************************
 ** Function name:           fillCircleHelper
-** Description:             Support function for filled circle drawing
+** Description:             Support function for fillRoundRect()
 ***************************************************************************************/
 // Support drawing roundrects, changed to horizontal lines (faster in sprites)
 void TFT_eSPI::fillCircleHelper(int32_t x0, int32_t y0, int32_t r, uint8_t cornername, int32_t delta, uint32_t color)
@@ -1734,6 +1737,8 @@ void TFT_eSPI::fillCircleHelper(int32_t x0, int32_t y0, int32_t r, uint8_t corne
 
   while (y < r) {
     if (f >= 0) {
+      if (cornername & 0x1) drawFastHLine(x0 - y, y0 + r, y + y + delta, color);
+      if (cornername & 0x2) drawFastHLine(x0 - y, y0 - r, y + y + delta, color);
       r--;
       ddF_y += 2;
       f     += ddF_y;
@@ -1743,14 +1748,8 @@ void TFT_eSPI::fillCircleHelper(int32_t x0, int32_t y0, int32_t r, uint8_t corne
     ddF_x += 2;
     f     += ddF_x;
 
-    if (cornername & 0x1) {
-      drawFastHLine(x0 - r, y0 + y, r + r + delta, color);
-      drawFastHLine(x0 - y, y0 + r, y + y + delta, color);
-    }
-    if (cornername & 0x2) {
-      drawFastHLine(x0 - r, y0 - y, r + r + delta, color); // 11995, 1090
-      drawFastHLine(x0 - y, y0 - r, y + y + delta, color);
-    }
+    if (cornername & 0x1) drawFastHLine(x0 - r, y0 + y, r + r + delta, color);
+    if (cornername & 0x2) drawFastHLine(x0 - r, y0 - y, r + r + delta, color);
   }
 }
 

TFT_eSPI.h

@@ -16,7 +16,7 @@
 #ifndef _TFT_eSPIH_
 #define _TFT_eSPIH_
 
-#define TFT_ESPI_VERSION "2.1.9"
+#define TFT_ESPI_VERSION "2.2.0"
 
 /***************************************************************************************
 **                         Section 1: Load required header files

library.json

 {
   "name": "TFT_eSPI",
-  "version": "2.1.9",
+  "version": "2.2.0",
   "keywords": "Arduino, tft, ePaper, display, STM32, ESP8266, NodeMCU, ESP32, M5Stack, ILI9341, ST7735, ILI9163, S6D02A1, ILI9486, ST7789, RM68140",
   "description": "A TFT and ePaper SPI graphics library with optimisation for ESP8266, ESP32 and STM32",
   "repository":

library.properties

 name=TFT_eSPI
-version=2.1.9
+version=2.2.0
 author=Bodmer
 maintainer=Bodmer
 sentence=TFT graphics library for Arduino processors with performance optimisation for STM32, ESP8266 and ESP32