From a68d5b73e524dd36455db8d86489c8d5ea238703 Mon Sep 17 00:00:00 2001
From: Michael Fogleman <fogleman@gmail.com>
Date: Sun, 21 Feb 2016 16:20:17 -0500
Subject: [PATCH] QuadraticBezier

---
 bezier.go | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/bezier.go b/bezier.go
index 2d69cb8..f2cd7ab 100644
--- a/bezier.go
+++ b/bezier.go
@@ -2,6 +2,33 @@ package gg
 
 import "math"
 
+func quadratic(x0, y0, x1, y1, x2, y2, t float64) (x, y float64) {
+	u := 1 - t
+	a := u * u
+	b := 2 * u * t
+	c := t * t
+	x = a*x0 + b*x1 + c*x2
+	y = a*y0 + b*y1 + c*y2
+	return
+}
+
+func QuadraticBezier(x0, y0, x1, y1, x2, y2 float64) []Point {
+	l := (math.Hypot(x1-x0, y1-y0) +
+		math.Hypot(x2-x1, y2-y1))
+	n := int(l + 0.5)
+	if n < 4 {
+		n = 4
+	}
+	d := float64(n) - 1
+	result := make([]Point, n)
+	for i := 0; i < n; i++ {
+		t := float64(i) / d
+		x, y := quadratic(x0, y0, x1, y1, x2, y2, t)
+		result[i] = Point{x, y}
+	}
+	return result
+}
+
 func cubic(x0, y0, x1, y1, x2, y2, x3, y3, t float64) (x, y float64) {
 	u := 1 - t
 	a := u * u * u