From 70c352c34f448b4c4c3bb4250d1e477e28393037 Mon Sep 17 00:00:00 2001
From: Ashutosh <ashutoshshrm529@gmail.com>
Date: Mon, 16 Mar 2020 14:52:00 +0530
Subject: [PATCH] Ellipse Function Added. Need to test.

---
 keywords.txt            |  5 +++--
 src/ArduinoGraphics.cpp | 36 ++++++++++++++++++++++++++++++++++--
 src/ArduinoGraphics.h   |  2 +-
 3 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/keywords.txt b/keywords.txt
index 5c7d60b..dcdec65 100644
--- a/keywords.txt
+++ b/keywords.txt
@@ -10,8 +10,8 @@ Font	KEYWORD1
 Image	KEYWORD1
 
 ##########################################
-# Methods and Functions 
-##########################################	
+# Methods and Functions
+##########################################
 
 begin	KEYWORD2
 end	KEYWORD2
@@ -33,6 +33,7 @@ line	KEYWORD2
 point	KEYWORD2
 quad	KEYWORD2
 rect	KEYWORD2
+ellipse KEYWORD2
 
 text	KEYWORD2
 textFont	KEYWORD2
diff --git a/src/ArduinoGraphics.cpp b/src/ArduinoGraphics.cpp
index bedd1a7..75960af 100644
--- a/src/ArduinoGraphics.cpp
+++ b/src/ArduinoGraphics.cpp
@@ -184,6 +184,38 @@ void ArduinoGraphics::rect(int x, int y, int width, int height)
   }
 }
 
+void ArduinoGraphics::ellipse(int x, int y, int width, int height)
+{
+  if (!_stroke && !_fill) {
+    return;
+  }
+
+  int x1 = x;
+  int y1 = y;
+  int r1 = (width/2);
+  int r2 = (height/2);
+  int x2 = x1 + r1 - 1;
+
+  for(x = x1; x <= x2; x++) {
+      y2 = y1 + sqrt((1 - ((x * x)/(r1 * r1)))) * r2;
+      for(y = y1; y <= y2; y++) {
+          if ((y == y2) && _stroke) {
+            // stroke
+            set(x, y, _strokeR, _strokeG, _strokeB); // current point
+            set(x - (((x - x1) * 2)), y, _strokeR, _strokeG, _strokeB); // second reflection
+            set(x, y - (((y - y1) * 2)), _strokeR, _strokeG, _strokeB); // third reflection
+            set(x - (((x - x1) * 2)), y - (((y - y1) * 2)), _strokeR, _strokeG, _strokeB); // fourth reflection
+          } else if (_fill) {
+            // fill
+            set(x, y, _fillR, _fillG, _fillB); // current point
+            set(x - (((x - x1) * 2)), y, _fillR, _fillG, _fillB); // second reflection
+            set(x, y - (((y - y1) * 2)), _fillR, _fillG, _fillB); // third reflection
+            set(x - (((x - x1) * 2)), y - (((y - y1) * 2)), _fillR, _fillG, _fillB); // fourth reflection
+          }
+      }
+  }
+}
+
 void ArduinoGraphics::text(const char* str, int x, int y)
 {
   if (!_font || !_stroke) {
@@ -365,7 +397,7 @@ void ArduinoGraphics::beginText(int x, int y, uint8_t r, uint8_t g, uint8_t b)
 
   _textR = r;
   _textG = g;
-  _textB = b;  
+  _textB = b;
 }
 
 void ArduinoGraphics::beginText(int x, int y, uint32_t color)
@@ -482,7 +514,7 @@ void ArduinoGraphics::lineHigh(int x1, int y1, int x2, int y2)
     xi = -1;
     dx = -dx;
   }
-  
+
   int D = 2 * dx - dy;
   int x = x1;
 
diff --git a/src/ArduinoGraphics.h b/src/ArduinoGraphics.h
index f5468b0..6df5790 100644
--- a/src/ArduinoGraphics.h
+++ b/src/ArduinoGraphics.h
@@ -58,12 +58,12 @@ class ArduinoGraphics : public Print {
   void noStroke();
 
   //virtual void arc(int x, int y, int width, int height, int start, int stop);
-  //virtual void ellipse(int x, int y, int width, int height);
   virtual void line(int x1, int y1, int x2, int y2);
   virtual void point(int x, int y);
   //virtual void quad(int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4);
   //virtual void triangle(int x1, int y1, int x2, int y2, int x3, int y3);
   virtual void rect(int x, int y, int width, int height);
+  virtual void ellipse(int x, int y, int width, int height);
 
   virtual void text(const char* str, int x = 0, int y = 0);
   virtual void text(const String& str, int x = 0, int y = 0) { text(str.c_str(), x, y); }