diff --git a/README.md b/README.md
index 697d68d..0af92ba 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,7 @@ This package is still working in progress, more types would be added. Welcome an
 - Color Circle
 - Color Circle2
 - Circle Grid
+- Contour Line
 
 For these kinds of art, the package provides as many as parameters to control the appearance.
 
@@ -55,6 +56,7 @@ NewRandomShape(shapeNum int)
 NewColorCircle(circleNum int)
 NewColorCircle2(circleNum int)
 NewCircleGrid(circleNumMin, circleNumMax int)
+NewContourLine(lineNum int)
 ```
 
 ## Docs
@@ -190,24 +192,28 @@ func main() {
 
 ![](images/silksmoke.png)
 
-### Spiral Square
+### Contour Line
 
 ```go
 func main() {
 	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.MistyRose)
-	c.SetLineWidth(10)
-	c.SetLineColor(generativeart.Orange)
-	c.SetColorSchema(generativeart.Plasma)
-	c.SetForeground(generativeart.Tomato)
+	colors := []color.RGBA{
+		{0x58, 0x18, 0x45, 0xFF},
+		{0x90, 0x0C, 0x3F, 0xFF},
+		{0xC7, 0x00, 0x39, 0xFF},
+		{0xFF, 0x57, 0x33, 0xFF},
+		{0xFF, 0xC3, 0x0F, 0xFF},
+	}
+	c := generativeart.NewCanva(1600, 1600)
+	c.SetBackground(color.RGBA{0x1a, 0x06, 0x33, 0xFF})
 	c.FillBackground()
-	c.Draw(generativeart.NewSpiralSquare(40, 400, 0.05, true))
-	c.ToPNG("spiralsquare.png")
+	c.SetColorSchema(colors)
+	c.Draw(generativeart.NewContourLine(500))
+	c.ToPNG("contourline.png")
 }
 ```
 
-![](images/spiralsquare.png)
+![](images/contourline.png)
 
 ### Circle Loop
 
@@ -345,3 +351,4 @@ Thanks for the following sites and repos, I got lots of ideas, inspiration, code
 - https://editor.p5js.org/kenekk1/sketches/O44Dln5oo
 - https://openprocessing.org/sketch/1071233
 - https://twitter.com/okazz_
+- https://openprocessing.org/sketch/738638
diff --git a/contourline.go b/contourline.go
index 880df6f..5ef5f85 100644
--- a/contourline.go
+++ b/contourline.go
@@ -1,8 +1,8 @@
 package generativeart
 
 import (
-	"github.com/aquilax/go-perlin"
 	"github.com/fogleman/gg"
+	"github.com/jdxyw/generativeart/common"
 	"math"
 	"math/rand"
 )
@@ -11,6 +11,7 @@ type contourLine struct {
 	lineNum int
 }
 
+// NewContourLine returns a contourLine object.
 func NewContourLine(lineNum int) *contourLine {
 	return &contourLine{
 		lineNum: lineNum,
@@ -20,21 +21,21 @@ func NewContourLine(lineNum int) *contourLine {
 // Generative draws a contour line image.
 func (cl *contourLine) Generative(c *canva) {
 	ctex := gg.NewContextForRGBA(c.img)
-	noise := perlin.NewPerlin(2, 2, 3, rand.Int63())
-
+	//noise := perlin.NewPerlin(2, 2, 3, rand.Int63())
+	noise := common.NewPerlinNoise()
 	for i := 0; i < cl.lineNum; i++ {
 		cl := c.opts.colorSchema[rand.Intn(len(c.opts.colorSchema))]
+		x := rand.Float64() * float64(c.width)
+		y := rand.Float64() * float64(c.height)
 
-		for j := 0; j < 5; j++ {
-			x := rand.Float64() * float64(c.width)
-			y := rand.Float64() * float64(c.height)
+		for j := 0; j < 1500; j++ {
 
-			theta := noise.Noise2D(x/800.0, y/800.0) * math.Pi * 2 * 800
+			theta := noise.Noise(x/800.0, y/800.0, 0) * math.Pi * 2 * 800
 			x += math.Cos(theta) * 0.4
 			y += math.Sin(theta) * 0.4
 
 			ctex.SetColor(cl)
-			ctex.DrawEllipse(x, y, 1, 1)
+			ctex.DrawEllipse(x, y, 2, 2)
 			ctex.Fill()
 
 			if x > float64(c.width) || x < 0 || y > float64(c.height) || y < 0 || rand.Float64() < 0.001 {
diff --git a/docs/doc.md b/docs/doc.md
index 72e46ec..7a1394e 100644
--- a/docs/doc.md
+++ b/docs/doc.md
@@ -44,15 +44,24 @@ rs := NewRandomShape(150)
 
 ## Janus
 
-`Janus` would draws a image with multiple circles split at its center with random noise in the horizontal direction.
+`Janus` would draw an image with multiple circles split at its center with random noise in the horizontal direction.
 
 ### TODO
 
 ### parameters
 
+## Contour Line
+
+`Contour Line` uses `perlin noise` to do some flow field.
+
+### parameters
+
+- lineNum: It indicates how many lines.
+
+![](../images/contourline.png)
 ## Silk Sky
 
-`Silk Sky` would draws a image with multiple circles converge to one point or circle. 
+`Silk Sky` would draw an image with multiple circles converge to one point or one circle. 
 
 ### parameters
 
@@ -73,7 +82,7 @@ silkSky := NewSilkSky(circleNum int, sunRadius float64)
 
 - fn: The custom julia set function.
 - maxz: The maximum modulus length of a complex number.
-- xaixs, yaixs: The range for the X-Y coordination used to mapping the julia set number to the real pixel of the image. These should be positive number. It only indicates the first quadrant range.
+- xaixs, yaixs: The range for the X-Y coordination used to mapping the julia set number to the real pixel of the image. These should be positive. It only indicates the first quadrant range.
 
 ```go
 func julia1(z complex128) complex128 {
diff --git a/example/example_contourline.go b/example/example_contourline.go
index b472df7..9d36223 100644
--- a/example/example_contourline.go
+++ b/example/example_contourline.go
@@ -16,10 +16,10 @@ func main() {
 		{0xFF, 0x57, 0x33, 0xFF},
 		{0xFF, 0xC3, 0x0F, 0xFF},
 	}
-	c := generativeart.NewCanva(800, 800)
+	c := generativeart.NewCanva(1600, 1600)
 	c.SetBackground(color.RGBA{0x1a, 0x06, 0x33, 0xFF})
 	c.FillBackground()
 	c.SetColorSchema(colors)
-	c.Draw(generativeart.NewContourLine(200))
+	c.Draw(generativeart.NewContourLine(500))
 	c.ToPNG("contourline.png")
 }
diff --git a/images/contourline.png b/images/contourline.png
new file mode 100644
index 0000000..cdbf023
Binary files /dev/null and b/images/contourline.png differ