diff -r 000000000000 -r 88d965579617 components/u8g2/csrc/u8g2_circle.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/components/u8g2/csrc/u8g2_circle.c	Tue Oct 08 12:00:31 2019 +0200
@@ -0,0 +1,479 @@
+/*
+
+  u8g2_circle.c
+
+  Universal 8bit Graphics Library (https://github.com/olikraus/u8g2/)
+
+  Copyright (c) 2016, olikraus@gmail.com
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without modification, 
+  are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice, this list 
+    of conditions and the following disclaimer.
+    
+  * Redistributions in binary form must reproduce the above copyright notice, this 
+    list of conditions and the following disclaimer in the documentation and/or other 
+    materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
+  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
+  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
+  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
+  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
+  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+
+*/
+
+#include "u8g2.h"
+
+/*==============================================*/
+/* Circle */
+
+static void u8g2_draw_circle_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option) U8G2_NOINLINE;
+
+static void u8g2_draw_circle_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option)
+{
+    /* upper right */
+    if ( option & U8G2_DRAW_UPPER_RIGHT )
+    {
+      u8g2_DrawPixel(u8g2, x0 + x, y0 - y);
+      u8g2_DrawPixel(u8g2, x0 + y, y0 - x);
+    }
+    
+    /* upper left */
+    if ( option & U8G2_DRAW_UPPER_LEFT )
+    {
+      u8g2_DrawPixel(u8g2, x0 - x, y0 - y);
+      u8g2_DrawPixel(u8g2, x0 - y, y0 - x);
+    }
+    
+    /* lower right */
+    if ( option & U8G2_DRAW_LOWER_RIGHT )
+    {
+      u8g2_DrawPixel(u8g2, x0 + x, y0 + y);
+      u8g2_DrawPixel(u8g2, x0 + y, y0 + x);
+    }
+    
+    /* lower left */
+    if ( option & U8G2_DRAW_LOWER_LEFT )
+    {
+      u8g2_DrawPixel(u8g2, x0 - x, y0 + y);
+      u8g2_DrawPixel(u8g2, x0 - y, y0 + x);
+    }
+}
+
+static void u8g2_draw_circle(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rad, uint8_t option)
+{
+    u8g2_int_t f;
+    u8g2_int_t ddF_x;
+    u8g2_int_t ddF_y;
+    u8g2_uint_t x;
+    u8g2_uint_t y;
+
+    f = 1;
+    f -= rad;
+    ddF_x = 1;
+    ddF_y = 0;
+    ddF_y -= rad;
+    ddF_y *= 2;
+    x = 0;
+    y = rad;
+
+    u8g2_draw_circle_section(u8g2, x, y, x0, y0, option);
+    
+    while ( x < y )
+    {
+      if (f >= 0) 
+      {
+        y--;
+        ddF_y += 2;
+        f += ddF_y;
+      }
+      x++;
+      ddF_x += 2;
+      f += ddF_x;
+
+      u8g2_draw_circle_section(u8g2, x, y, x0, y0, option);    
+    }
+}
+
+void u8g2_DrawCircle(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rad, uint8_t option)
+{
+  /* check for bounding box */
+#ifdef U8G2_WITH_INTERSECTION
+  {
+    if ( u8g2_IsIntersection(u8g2, x0-rad, y0-rad, x0+rad+1, y0+rad+1) == 0 ) 
+      return;
+  }
+#endif /* U8G2_WITH_INTERSECTION */
+  
+  
+  /* draw circle */
+  u8g2_draw_circle(u8g2, x0, y0, rad, option);
+}
+
+/*==============================================*/
+/* Disk */
+
+static void u8g2_draw_disc_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option) U8G2_NOINLINE;
+
+static void u8g2_draw_disc_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option)
+{
+    /* upper right */
+    if ( option & U8G2_DRAW_UPPER_RIGHT )
+    {
+      u8g2_DrawVLine(u8g2, x0+x, y0-y, y+1);
+      u8g2_DrawVLine(u8g2, x0+y, y0-x, x+1);
+    }
+    
+    /* upper left */
+    if ( option & U8G2_DRAW_UPPER_LEFT )
+    {
+      u8g2_DrawVLine(u8g2, x0-x, y0-y, y+1);
+      u8g2_DrawVLine(u8g2, x0-y, y0-x, x+1);
+    }
+    
+    /* lower right */
+    if ( option & U8G2_DRAW_LOWER_RIGHT )
+    {
+      u8g2_DrawVLine(u8g2, x0+x, y0, y+1);
+      u8g2_DrawVLine(u8g2, x0+y, y0, x+1);
+    }
+    
+    /* lower left */
+    if ( option & U8G2_DRAW_LOWER_LEFT )
+    {
+      u8g2_DrawVLine(u8g2, x0-x, y0, y+1);
+      u8g2_DrawVLine(u8g2, x0-y, y0, x+1);
+    }
+}
+
+static void u8g2_draw_disc(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rad, uint8_t option)
+{
+  u8g2_int_t f;
+  u8g2_int_t ddF_x;
+  u8g2_int_t ddF_y;
+  u8g2_uint_t x;
+  u8g2_uint_t y;
+
+  f = 1;
+  f -= rad;
+  ddF_x = 1;
+  ddF_y = 0;
+  ddF_y -= rad;
+  ddF_y *= 2;
+  x = 0;
+  y = rad;
+
+  u8g2_draw_disc_section(u8g2, x, y, x0, y0, option);
+  
+  while ( x < y )
+  {
+    if (f >= 0) 
+    {
+      y--;
+      ddF_y += 2;
+      f += ddF_y;
+    }
+    x++;
+    ddF_x += 2;
+    f += ddF_x;
+
+    u8g2_draw_disc_section(u8g2, x, y, x0, y0, option);    
+  }
+}
+
+void u8g2_DrawDisc(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rad, uint8_t option)
+{
+  /* check for bounding box */
+#ifdef U8G2_WITH_INTERSECTION
+  {
+    if ( u8g2_IsIntersection(u8g2, x0-rad, y0-rad, x0+rad+1, y0+rad+1) == 0 ) 
+      return;
+  }
+#endif /* U8G2_WITH_INTERSECTION */
+  
+  /* draw disc */
+  u8g2_draw_disc(u8g2, x0, y0, rad, option);
+}
+
+/*==============================================*/
+/* Ellipse */
+
+/*
+  Source: 
+    Foley, Computer Graphics, p 90
+*/
+static void u8g2_draw_ellipse_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option) U8G2_NOINLINE;
+static void u8g2_draw_ellipse_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option)
+{
+    /* upper right */
+    if ( option & U8G2_DRAW_UPPER_RIGHT )
+    {
+      u8g2_DrawPixel(u8g2, x0 + x, y0 - y);
+    }
+    
+    /* upper left */
+    if ( option & U8G2_DRAW_UPPER_LEFT )
+    {
+      u8g2_DrawPixel(u8g2, x0 - x, y0 - y);
+    }
+    
+    /* lower right */
+    if ( option & U8G2_DRAW_LOWER_RIGHT )
+    {
+      u8g2_DrawPixel(u8g2, x0 + x, y0 + y);
+    }
+    
+    /* lower left */
+    if ( option & U8G2_DRAW_LOWER_LEFT )
+    {
+      u8g2_DrawPixel(u8g2, x0 - x, y0 + y);
+    }
+}
+
+static void u8g2_draw_ellipse(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rx, u8g2_uint_t ry, uint8_t option)
+{
+  u8g2_uint_t x, y;
+  u8g2_long_t xchg, ychg;
+  u8g2_long_t err;
+  u8g2_long_t rxrx2;
+  u8g2_long_t ryry2;
+  u8g2_long_t stopx, stopy;
+  
+  rxrx2 = rx;
+  rxrx2 *= rx;
+  rxrx2 *= 2;
+  
+  ryry2 = ry;
+  ryry2 *= ry;
+  ryry2 *= 2;
+  
+  x = rx;
+  y = 0;
+  
+  xchg = 1;
+  xchg -= rx;
+  xchg -= rx;
+  xchg *= ry;
+  xchg *= ry;
+  
+  ychg = rx;
+  ychg *= rx;
+  
+  err = 0;
+  
+  stopx = ryry2;
+  stopx *= rx;
+  stopy = 0;
+  
+  while( stopx >= stopy )
+  {
+    u8g2_draw_ellipse_section(u8g2, x, y, x0, y0, option);
+    y++;
+    stopy += rxrx2;
+    err += ychg;
+    ychg += rxrx2;
+    if ( 2*err+xchg > 0 )
+    {
+      x--;
+      stopx -= ryry2;
+      err += xchg;
+      xchg += ryry2;      
+    }
+  }
+
+  x = 0;
+  y = ry;
+  
+  xchg = ry;
+  xchg *= ry;
+  
+  ychg = 1;
+  ychg -= ry;
+  ychg -= ry;
+  ychg *= rx;
+  ychg *= rx;
+  
+  err = 0;
+  
+  stopx = 0;
+
+  stopy = rxrx2;
+  stopy *= ry;
+  
+
+  while( stopx <= stopy )
+  {
+    u8g2_draw_ellipse_section(u8g2, x, y, x0, y0, option);
+    x++;
+    stopx += ryry2;
+    err += xchg;
+    xchg += ryry2;
+    if ( 2*err+ychg > 0 )
+    {
+      y--;
+      stopy -= rxrx2;
+      err += ychg;
+      ychg += rxrx2;
+    }
+  }
+  
+}
+
+void u8g2_DrawEllipse(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rx, u8g2_uint_t ry, uint8_t option)
+{
+  /* check for bounding box */
+#ifdef U8G2_WITH_INTERSECTION
+  {
+    if ( u8g2_IsIntersection(u8g2, x0-rx, y0-ry, x0+rx+1, y0+ry+1) == 0 ) 
+      return;
+  }
+#endif /* U8G2_WITH_INTERSECTION */
+  
+  u8g2_draw_ellipse(u8g2, x0, y0, rx, ry, option);
+}
+
+/*==============================================*/
+/* Filled Ellipse */
+
+static void u8g2_draw_filled_ellipse_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option) U8G2_NOINLINE;
+static void u8g2_draw_filled_ellipse_section(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t x0, u8g2_uint_t y0, uint8_t option)
+{
+    /* upper right */
+    if ( option & U8G2_DRAW_UPPER_RIGHT )
+    {
+      u8g2_DrawVLine(u8g2, x0+x, y0-y, y+1);
+    }
+    
+    /* upper left */
+    if ( option & U8G2_DRAW_UPPER_LEFT )
+    {
+      u8g2_DrawVLine(u8g2, x0-x, y0-y, y+1);
+    }
+    
+    /* lower right */
+    if ( option & U8G2_DRAW_LOWER_RIGHT )
+    {
+      u8g2_DrawVLine(u8g2, x0+x, y0, y+1);
+    }
+    
+    /* lower left */
+    if ( option & U8G2_DRAW_LOWER_LEFT )
+    {
+      u8g2_DrawVLine(u8g2, x0-x, y0, y+1);
+    }
+}
+
+static void u8g2_draw_filled_ellipse(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rx, u8g2_uint_t ry, uint8_t option)
+{
+  u8g2_uint_t x, y;
+  u8g2_long_t xchg, ychg;
+  u8g2_long_t err;
+  u8g2_long_t rxrx2;
+  u8g2_long_t ryry2;
+  u8g2_long_t stopx, stopy;
+  
+  rxrx2 = rx;
+  rxrx2 *= rx;
+  rxrx2 *= 2;
+  
+  ryry2 = ry;
+  ryry2 *= ry;
+  ryry2 *= 2;
+  
+  x = rx;
+  y = 0;
+  
+  xchg = 1;
+  xchg -= rx;
+  xchg -= rx;
+  xchg *= ry;
+  xchg *= ry;
+  
+  ychg = rx;
+  ychg *= rx;
+  
+  err = 0;
+  
+  stopx = ryry2;
+  stopx *= rx;
+  stopy = 0;
+  
+  while( stopx >= stopy )
+  {
+    u8g2_draw_filled_ellipse_section(u8g2, x, y, x0, y0, option);
+    y++;
+    stopy += rxrx2;
+    err += ychg;
+    ychg += rxrx2;
+    if ( 2*err+xchg > 0 )
+    {
+      x--;
+      stopx -= ryry2;
+      err += xchg;
+      xchg += ryry2;      
+    }
+  }
+
+  x = 0;
+  y = ry;
+  
+  xchg = ry;
+  xchg *= ry;
+  
+  ychg = 1;
+  ychg -= ry;
+  ychg -= ry;
+  ychg *= rx;
+  ychg *= rx;
+  
+  err = 0;
+  
+  stopx = 0;
+
+  stopy = rxrx2;
+  stopy *= ry;
+  
+
+  while( stopx <= stopy )
+  {
+    u8g2_draw_filled_ellipse_section(u8g2, x, y, x0, y0, option);
+    x++;
+    stopx += ryry2;
+    err += xchg;
+    xchg += ryry2;
+    if ( 2*err+ychg > 0 )
+    {
+      y--;
+      stopy -= rxrx2;
+      err += ychg;
+      ychg += rxrx2;
+    }
+  }
+  
+}
+
+void u8g2_DrawFilledEllipse(u8g2_t *u8g2, u8g2_uint_t x0, u8g2_uint_t y0, u8g2_uint_t rx, u8g2_uint_t ry, uint8_t option)
+{
+  /* check for bounding box */
+#ifdef U8G2_WITH_INTERSECTION
+  {
+    if ( u8g2_IsIntersection(u8g2, x0-rx, y0-ry, x0+rx+1, y0+ry+1) == 0 ) 
+      return;
+  }
+#endif /* U8G2_WITH_INTERSECTION */
+  
+  u8g2_draw_filled_ellipse(u8g2, x0, y0, rx, ry, option);
+}
+
+