diff --git a/README.md b/README.md
index 9e44ee2..ccc0839 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,6 @@
 [![Go Report Card](https://goreportcard.com/badge/github.com/jdxyw/generativeart)](https://goreportcard.com/report/github.com/jdxyw/generativeart)
 [![GitHub license](https://img.shields.io/badge/license-MIT-blue.svg)](https://raw.githubusercontent.com/jdxyw/generativeart/master/LICENSE)
 
-
 `generativeart` is a `Go` package to generate many kinds of generative art. The goal is to collect some excellent generative art (implemented in `R` or `Processing`), and rewrite them in `Go` again. I would paste the original link at the end of this README(If I remember, you can also submit a PR if you found I missed something.). Currently, it supports the following type.
 
 ## Buy me a coffee
@@ -36,6 +35,7 @@ This package is still working in progress. More types would be added. Welcome an
 - Noise Line
 - Ocean Fish
 - Circle Loop2
+- Pixel Hole
 
 For these kinds of art, the package provides as many parameters to control the appearance.
 
@@ -68,6 +68,7 @@ NewCircleGrid(circleNumMin, circleNumMax int)
 NewContourLine(lineNum int)
 NewNoiseLine(n int)
 NewCircleLoop2(depth int)
+NewPixelHole(dotN int)
 ```
 
 ## Docs
@@ -77,37 +78,39 @@ You could find the docs in the [doc](./docs).
 ## Examples
 
 You could find examples for all types under [example](./example).
+
 ## General Options
 
 ```go
 type Options struct {
-	background  color.RGBA
-	foreground  color.RGBA
-	lineColor   color.RGBA
-	lineWidth   float64
-	colorSchema []color.RGBA
-	nIters      int
-	alpha       int
+ background  color.RGBA
+ foreground  color.RGBA
+ lineColor   color.RGBA
+ lineWidth   float64
+ colorSchema []color.RGBA
+ nIters      int
+ alpha       int
 }
 ```
 
 The `Options` is a global option for the whole `canva`. It includes those general parameters used by different kinds of types, such as `background`, `lineColor`, and `colorScheme`.
 
 For those parameters specified for different kinds of art types, they have their own `struct`.
+
 ## Usage and example
 
 ### Junas
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
-	c.FillBackground()
-	c.SetColorSchema(generativeart.DarkRed)
-	c.SetForeground(generativeart.LightPink)
-	c.Draw(generativeart.NewJanus(10, 0.2))
-	c.ToPNG("janus.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(generativeart.Black)
+ c.FillBackground()
+ c.SetColorSchema(generativeart.DarkRed)
+ c.SetForeground(generativeart.LightPink)
+ c.Draw(generativeart.NewJanus(10, 0.2))
+ c.ToPNG("janus.png")
 }
 ```
 
@@ -117,19 +120,19 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.White)
-	c.FillBackground()
-	c.SetColorSchema([]color.RGBA{
-		{0xCF, 0x2B, 0x34, 0xFF},
-		{0xF0, 0x8F, 0x46, 0xFF},
-		{0xF0, 0xC1, 0x29, 0xFF},
-		{0x19, 0x6E, 0x94, 0xFF},
-		{0x35, 0x3A, 0x57, 0xFF},
-	})
-	c.Draw(generativeart.NewRandomShape(150))
-	c.ToPNG("randomshape.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(generativeart.White)
+ c.FillBackground()
+ c.SetColorSchema([]color.RGBA{
+  {0xCF, 0x2B, 0x34, 0xFF},
+  {0xF0, 0x8F, 0x46, 0xFF},
+  {0xF0, 0xC1, 0x29, 0xFF},
+  {0x19, 0x6E, 0x94, 0xFF},
+  {0x35, 0x3A, 0x57, 0xFF},
+ })
+ c.Draw(generativeart.NewRandomShape(150))
+ c.ToPNG("randomshape.png")
 }
 ```
 
@@ -139,20 +142,20 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	colors := []color.RGBA{
-		{0x11, 0x60, 0xC6, 0xFF},
-		{0xFD, 0xD9, 0x00, 0xFF},
-		{0xF5, 0xB4, 0xF8, 0xFF},
-		{0xEF, 0x13, 0x55, 0xFF},
-		{0xF4, 0x9F, 0x0A, 0xFF},
-	}
-	c := generativeart.NewCanva(800, 800)
-	c.SetBackground(generativeart.White)
-	c.FillBackground()
-	c.SetColorSchema(colors)
-	c.Draw(generativeart.NewColorCircle2(30))
-	c.ToPNG("colorcircle2.png")
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0x11, 0x60, 0xC6, 0xFF},
+  {0xFD, 0xD9, 0x00, 0xFF},
+  {0xF5, 0xB4, 0xF8, 0xFF},
+  {0xEF, 0x13, 0x55, 0xFF},
+  {0xF4, 0x9F, 0x0A, 0xFF},
+ }
+ c := generativeart.NewCanva(800, 800)
+ c.SetBackground(generativeart.White)
+ c.FillBackground()
+ c.SetColorSchema(colors)
+ c.Draw(generativeart.NewColorCircle2(30))
+ c.ToPNG("colorcircle2.png")
 }
 ```
 
@@ -162,22 +165,22 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	colors := []color.RGBA{
-		{0xED, 0x34, 0x41, 0xFF},
-		{0xFF, 0xD6, 0x30, 0xFF},
-		{0x32, 0x9F, 0xE3, 0xFF},
-		{0x15, 0x42, 0x96, 0xFF},
-		{0x00, 0x00, 0x00, 0xFF},
-		{0xFF, 0xFF, 0xFF, 0xFF},
-	}
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(color.RGBA{0xDF, 0xEB, 0xF5, 0xFF})
-	c.FillBackground()
-	c.SetColorSchema(colors)
-	c.SetLineWidth(2.0)
-	c.Draw(generativeart.NewCircleGrid(4, 6))
-	c.ToPNG("circlegrid.png")
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0xED, 0x34, 0x41, 0xFF},
+  {0xFF, 0xD6, 0x30, 0xFF},
+  {0x32, 0x9F, 0xE3, 0xFF},
+  {0x15, 0x42, 0x96, 0xFF},
+  {0x00, 0x00, 0x00, 0xFF},
+  {0xFF, 0xFF, 0xFF, 0xFF},
+ }
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(color.RGBA{0xDF, 0xEB, 0xF5, 0xFF})
+ c.FillBackground()
+ c.SetColorSchema(colors)
+ c.SetLineWidth(2.0)
+ c.Draw(generativeart.NewCircleGrid(4, 6))
+ c.ToPNG("circlegrid.png")
 }
 ```
 
@@ -187,40 +190,64 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	colors := []color.RGBA{
-		{0xF9, 0xC8, 0x0E, 0xFF},
-		{0xF8, 0x66, 0x24, 0xFF},
-		{0xEA, 0x35, 0x46, 0xFF},
-		{0x66, 0x2E, 0x9B, 0xFF},
-		{0x43, 0xBC, 0xCD, 0xFF},
-	}
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(color.RGBA{8, 10, 20, 255})
-	c.FillBackground()
-	c.SetColorSchema(colors)
-	c.Draw(generativeart.NewCircleLoop2(7))
-	c.ToPNG("colorloop2.png")
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0xF9, 0xC8, 0x0E, 0xFF},
+  {0xF8, 0x66, 0x24, 0xFF},
+  {0xEA, 0x35, 0x46, 0xFF},
+  {0x66, 0x2E, 0x9B, 0xFF},
+  {0x43, 0xBC, 0xCD, 0xFF},
+ }
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(color.RGBA{8, 10, 20, 255})
+ c.FillBackground()
+ c.SetColorSchema(colors)
+ c.Draw(generativeart.NewCircleLoop2(7))
+ c.ToPNG("colorloop2.png")
 }
 ```
 
 ![](images/colorloop2.png)
 
+## Pixel Hole
+
+```go
+func main() {
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0xF9, 0xC8, 0x0E, 0xFF},
+  {0xF8, 0x66, 0x24, 0xFF},
+  {0xEA, 0x35, 0x46, 0xFF},
+  {0x66, 0x2E, 0x9B, 0xFF},
+  {0x43, 0xBC, 0xCD, 0xFF},
+ }
+ c := generativeart.NewCanva(800, 800)
+ c.SetBackground(common.Black)
+ c.FillBackground()
+ c.SetColorSchema(colors)
+ c.SetIterations(1200)
+ c.Draw(generativeart.NewPixelHole(60))
+ c.ToPNG("pixelhole.png")
+}
+```
+
+![](images/pixelhole.png)
+
 ### Silk Smoke
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
-	c.SetLineWidth(1.0)
-	c.SetLineColor(generativeart.MediumAquamarine)
-	c.SetAlpha(30)
-	c.SetColorSchema(generativeart.Plasma)
-	c.SetIterations(4)
-	c.FillBackground()
-	c.Draw(generativeart.NewSilkSmoke(400, 20, 0.2, 2, 10, 30, false))
-	c.ToPNG("silksmoke.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(generativeart.Black)
+ c.SetLineWidth(1.0)
+ c.SetLineColor(generativeart.MediumAquamarine)
+ c.SetAlpha(30)
+ c.SetColorSchema(generativeart.Plasma)
+ c.SetIterations(4)
+ c.FillBackground()
+ c.Draw(generativeart.NewSilkSmoke(400, 20, 0.2, 2, 10, 30, false))
+ c.ToPNG("silksmoke.png")
 }
 ```
 
@@ -230,20 +257,20 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	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.SetColorSchema(colors)
-	c.Draw(generativeart.NewContourLine(500))
-	c.ToPNG("contourline.png")
+ rand.Seed(time.Now().Unix())
+ 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.SetColorSchema(colors)
+ c.Draw(generativeart.NewContourLine(500))
+ c.ToPNG("contourline.png")
 }
 ```
 
@@ -253,20 +280,20 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	colors := []color.RGBA{
-		{0x06, 0x7B, 0xC2, 0xFF},
-		{0x84, 0xBC, 0xDA, 0xFF},
-		{0xEC, 0xC3, 0x0B, 0xFF},
-		{0xF3, 0x77, 0x48, 0xFF},
-		{0xD5, 0x60, 0x62, 0xFF},
-	}
-	c := generativeart.NewCanva(1000, 1000)
-	c.SetBackground(color.RGBA{0xF0, 0xFE, 0xFF, 0xFF})
-	c.FillBackground()
-	c.SetColorSchema(colors)
-	c.Draw(generativeart.NewNoiseLine(1000))
-	c.ToPNG("noiseline.png")
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0x06, 0x7B, 0xC2, 0xFF},
+  {0x84, 0xBC, 0xDA, 0xFF},
+  {0xEC, 0xC3, 0x0B, 0xFF},
+  {0xF3, 0x77, 0x48, 0xFF},
+  {0xD5, 0x60, 0x62, 0xFF},
+ }
+ c := generativeart.NewCanva(1000, 1000)
+ c.SetBackground(color.RGBA{0xF0, 0xFE, 0xFF, 0xFF})
+ c.FillBackground()
+ c.SetColorSchema(colors)
+ c.Draw(generativeart.NewNoiseLine(1000))
+ c.ToPNG("noiseline.png")
 }
 ```
 
@@ -276,15 +303,15 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(2080, 2080)
-	c.SetBackground(color.RGBA{230, 230, 230, 255})
-	c.SetLineWidth(10)
-	c.SetIterations(4000)
-	c.SetColorSchema(generativeart.Plasma)
-	c.FillBackground()
-	c.Draw(generativeart.NewDotLine(100, 20, 50, false))
-	c.ToPNG("dotline.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(2080, 2080)
+ c.SetBackground(color.RGBA{230, 230, 230, 255})
+ c.SetLineWidth(10)
+ c.SetIterations(4000)
+ c.SetColorSchema(generativeart.Plasma)
+ c.FillBackground()
+ c.Draw(generativeart.NewDotLine(100, 20, 50, false))
+ c.ToPNG("dotline.png")
 }
 ```
 
@@ -294,18 +321,18 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	colors := []color.RGBA{
-		{0xCF, 0x2B, 0x34, 0xFF},
-		{0xF0, 0x8F, 0x46, 0xFF},
-		{0xF0, 0xC1, 0x29, 0xFF},
-		{0x19, 0x6E, 0x94, 0xFF},
-		{0x35, 0x3A, 0x57, 0xFF},
-	}
-	c := generativeart.NewCanva(500, 500)
-	c.SetColorSchema(colors)
-	c.Draw(generativeart.NewOceanFish(100, 8))
-	c.ToPNG("oceanfish.png")
+ rand.Seed(time.Now().Unix())
+ colors := []color.RGBA{
+  {0xCF, 0x2B, 0x34, 0xFF},
+  {0xF0, 0x8F, 0x46, 0xFF},
+  {0xF0, 0xC1, 0x29, 0xFF},
+  {0x19, 0x6E, 0x94, 0xFF},
+  {0x35, 0x3A, 0x57, 0xFF},
+ }
+ c := generativeart.NewCanva(500, 500)
+ c.SetColorSchema(colors)
+ c.Draw(generativeart.NewOceanFish(100, 8))
+ c.ToPNG("oceanfish.png")
 }
 ```
 
@@ -315,40 +342,39 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
-	c.SetLineWidth(1)
-	c.SetLineColor(generativeart.Orange)
-	c.SetAlpha(30)
-	c.SetIterations(1000)
-	c.FillBackground()
-	c.Draw(generativeart.NewCircleLoop(100))
-	c.ToPNG("circleloop.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(generativeart.Black)
+ c.SetLineWidth(1)
+ c.SetLineColor(generativeart.Orange)
+ c.SetAlpha(30)
+ c.SetIterations(1000)
+ c.FillBackground()
+ c.Draw(generativeart.NewCircleLoop(100))
+ c.ToPNG("circleloop.png")
 }
 ```
 
 ![](images/circleloop.png)
 
-
 ### Julia Set
 
 ```go
 func julia1(z complex128) complex128 {
-	c := complex(-0.1, 0.651)
-	z = z*z + c
+ c := complex(-0.1, 0.651)
+ z = z*z + c
 
-	return z
+ return z
 }
 
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetIterations(800)
-	c.SetColorSchema(generativeart.Viridis)
-	c.FillBackground()
-	c.Draw(generativeart.NewJulia(julia1, 40, 1.5, 1.5))
-	c.ToPNG("julia.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetIterations(800)
+ c.SetColorSchema(generativeart.Viridis)
+ c.FillBackground()
+ c.Draw(generativeart.NewJulia(julia1, 40, 1.5, 1.5))
+ c.ToPNG("julia.png")
 }
 ```
 
@@ -358,11 +384,11 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(600, 600)
-	c.SetAlpha(10)
-	c.Draw(generativeart.NewSilkSky(15, 5))
-	c.ToPNG("silksky.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(600, 600)
+ c.SetAlpha(10)
+ c.Draw(generativeart.NewSilkSky(15, 5))
+ c.ToPNG("silksky.png")
 }
 ```
 
@@ -372,14 +398,14 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(600, 600)
-	c.SetBackground(generativeart.Azure)
-	c.SetLineWidth(3)
-	c.SetLineColor(generativeart.Orange)
-	c.FillBackground()
-	c.Draw(generativeart.NewMaze(20))
-	c.ToPNG("maze.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(600, 600)
+ c.SetBackground(generativeart.Azure)
+ c.SetLineWidth(3)
+ c.SetLineColor(generativeart.Orange)
+ c.FillBackground()
+ c.Draw(generativeart.NewMaze(20))
+ c.ToPNG("maze.png")
 }
 ```
 
@@ -389,21 +415,21 @@ func main() {
 
 ```go
 func main() {
-	rand.Seed(time.Now().Unix())
-	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.MistyRose)
-	c.SetLineWidth(1.0)
-	c.SetLineColor(color.RGBA{
-		R: 122,
-		G: 122,
-		B: 122,
-		A: 30,
-	})
-	c.SetColorSchema(generativeart.Plasma)
-	c.SetIterations(4)
-	c.FillBackground()
-	c.Draw(generativeart.NewRandCicle(30, 80, 0.2, 2, 10, 30, true))
-	c.ToPNG("randcircle.png")
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(generativeart.MistyRose)
+ c.SetLineWidth(1.0)
+ c.SetLineColor(color.RGBA{
+  R: 122,
+  G: 122,
+  B: 122,
+  A: 30,
+ })
+ c.SetColorSchema(generativeart.Plasma)
+ c.SetIterations(4)
+ c.FillBackground()
+ c.Draw(generativeart.NewRandCicle(30, 80, 0.2, 2, 10, 30, true))
+ c.ToPNG("randcircle.png")
 }
 ```
 
@@ -417,19 +443,20 @@ func main() {
 
 Thanks for the following sites and repos, I got lots of ideas, inspiration, code, and tricks from them. The list would be very long; sorry for forgetting some of them.
 
-- https://inconvergent.net/
-- https://fronkonstin.com/
-- https://github.com/aschinchon/cyclic-cellular-automata
-- https://github.com/armdz/ProcessingSketchs
-- https://github.com/Mr-Slesser/Generative-Art-And-Fractals
-- https://github.com/cdr6934/Generative-Processing-Experiments
-- https://github.com/pkd2512/inktober2017
-- http://blog.dragonlab.de/2015/03/generative-art-week-1
-- https://editor.p5js.org/kenekk1/sketches/Ly-5XYvKX
-- http://paulbourke.net/fractals/peterdejong/
-- https://editor.p5js.org/kenekk1/sketches/O44Dln5oo
-- https://openprocessing.org/sketch/1071233
-- https://twitter.com/okazz_
-- https://openprocessing.org/sketch/738638
-- https://openprocessing.org/sketch/1102157
-- https://openprocessing.org/sketch/1071233
\ No newline at end of file
+- <https://inconvergent.net/>
+- <https://fronkonstin.com/>
+- <https://github.com/aschinchon/cyclic-cellular-automata>
+- <https://github.com/armdz/ProcessingSketchs>
+- <https://github.com/Mr-Slesser/Generative-Art-And-Fractals>
+- <https://github.com/cdr6934/Generative-Processing-Experiments>
+- <https://github.com/pkd2512/inktober2017>
+- <http://blog.dragonlab.de/2015/03/generative-art-week-1>
+- <https://editor.p5js.org/kenekk1/sketches/Ly-5XYvKX>
+- <http://paulbourke.net/fractals/peterdejong/>
+- <https://editor.p5js.org/kenekk1/sketches/O44Dln5oo>
+- <https://openprocessing.org/sketch/1071233>
+- <https://twitter.com/okazz_>
+- <https://openprocessing.org/sketch/738638>
+- <https://openprocessing.org/sketch/1102157>
+- <https://openprocessing.org/sketch/1071233>
+- <https://openprocessing.org/user/139364>
diff --git a/common/calculation.go b/common/calculation.go
index 3153364..b69507b 100644
--- a/common/calculation.go
+++ b/common/calculation.go
@@ -1,6 +1,9 @@
 package common
 
-import "math"
+import (
+	"image/color"
+	"math"
+)
 
 // Constrain returns a value between a minimum and maximum value.
 func Constrain(val, low, high float64) float64 {
@@ -17,3 +20,13 @@ func Remap(n, start1, stop1, start2, stop2 float64) float64 {
 		return Constrain(newval, stop2, start2)
 	}
 }
+
+// LerpColor blends two colors to find a third color somewhere between them.
+func LerpColor(c1, c2 color.RGBA, ratio float64) color.RGBA {
+	r := uint8(float64(c1.R)*ratio + float64(c2.R)*(1-ratio))
+	g := uint8(float64(c1.G)*ratio + float64(c2.G)*(1-ratio))
+	b := uint8(float64(c1.B)*ratio + float64(c2.B)*(1-ratio))
+	a := uint8(float64(c1.A)*ratio + float64(c2.A)*(1-ratio))
+
+	return color.RGBA{r, g, b, a}
+}
diff --git a/color.go b/common/color.go
similarity index 99%
rename from color.go
rename to common/color.go
index 75c6994..ccb955e 100644
--- a/color.go
+++ b/common/color.go
@@ -1,4 +1,4 @@
-package generativeart
+package common
 
 import "image/color"
 
diff --git a/docs/doc.md b/docs/doc.md
index 1371d18..73decb5 100644
--- a/docs/doc.md
+++ b/docs/doc.md
@@ -136,4 +136,18 @@ o := generativeart.NewOceanFish(100, 8)
 cl := generativeart.NewCircleLoop2(7)
 ```
 
-![](../images/colorloop2.png)
\ No newline at end of file
+![](../images/colorloop2.png)
+
+## Pixel Hole
+
+`Pixel Hole` draws a hole with colored dots.
+
+### parameters
+
+- dotN: The number of point in each iteration.
+
+```go
+ph := generativeart.NewPixelHole(60)
+```
+
+![](../images/pixelhole.png)
\ No newline at end of file
diff --git a/example/example_circleline.go b/example/example_circleline.go
index 40065ad..828b412 100644
--- a/example/example_circleline.go
+++ b/example/example_circleline.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,9 +10,9 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(600, 600)
-	c.SetBackground(generativeart.Tan)
+	c.SetBackground(common.Tan)
 	c.SetLineWidth(1.0)
-	c.SetLineColor(generativeart.LightPink)
+	c.SetLineColor(common.LightPink)
 	c.FillBackground()
 	c.Draw(generativeart.NewCircleLine(0.02, 600, 1.5, 2, 2))
 	c.ToPNG("circleline.png")
diff --git a/example/example_circleloop.go b/example/example_circleloop.go
index c9ea2ca..fed6e38 100644
--- a/example/example_circleloop.go
+++ b/example/example_circleloop.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,9 +10,9 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
+	c.SetBackground(common.Black)
 	c.SetLineWidth(1)
-	c.SetLineColor(generativeart.Orange)
+	c.SetLineColor(common.Orange)
 	c.SetAlpha(30)
 	c.SetIterations(1000)
 	c.FillBackground()
diff --git a/example/example_colorcircle.go b/example/example_colorcircle.go
index b44f458..0737bd1 100644
--- a/example/example_colorcircle.go
+++ b/example/example_colorcircle.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -20,7 +21,7 @@ func main() {
 		{0xFF, 0xFF, 0xFF, 0xFF},
 	}
 	c := generativeart.NewCanva(1000, 1000)
-	c.SetBackground(generativeart.White)
+	c.SetBackground(common.White)
 	c.FillBackground()
 	c.SetColorSchema(colors)
 	c.Draw(generativeart.NewColorCircle(500))
diff --git a/example/example_colorcircle2.go b/example/example_colorcircle2.go
index bd778f7..d0a0f5e 100644
--- a/example/example_colorcircle2.go
+++ b/example/example_colorcircle2.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -17,7 +18,7 @@ func main() {
 		{0xF4, 0x9F, 0x0A, 0xFF},
 	}
 	c := generativeart.NewCanva(800, 800)
-	c.SetBackground(generativeart.White)
+	c.SetBackground(common.White)
 	c.FillBackground()
 	c.SetColorSchema(colors)
 	c.Draw(generativeart.NewColorCircle2(30))
diff --git a/example/example_dotline.go b/example/example_dotline.go
index 91f907f..071dc35 100644
--- a/example/example_dotline.go
+++ b/example/example_dotline.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -13,7 +14,7 @@ func main() {
 	c.SetBackground(color.RGBA{230, 230, 230, 255})
 	c.SetLineWidth(10)
 	c.SetIterations(15000)
-	c.SetColorSchema(generativeart.Plasma)
+	c.SetColorSchema(common.Plasma)
 	c.FillBackground()
 	c.Draw(generativeart.NewDotLine(100, 20, 50, false))
 	c.ToPNG("dotline.png")
diff --git a/example/example_gridsquare.go b/example/example_gridsquare.go
index 2b41fd0..a92f97e 100644
--- a/example/example_gridsquare.go
+++ b/example/example_gridsquare.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,8 +10,8 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(600, 600)
-	c.SetBackground(generativeart.DarkPink[rand.Intn(5)])
-	c.SetColorSchema(generativeart.DarkPink)
+	c.SetBackground(common.DarkPink[rand.Intn(5)])
+	c.SetColorSchema(common.DarkPink)
 	c.Draw(generativeart.NewGirdSquares(24, 10, 0.2))
 	c.ToPNG("gsquare.png")
 }
diff --git a/example/example_janus.go b/example/example_janus.go
index 71b57b4..ba70c6f 100644
--- a/example/example_janus.go
+++ b/example/example_janus.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,10 +10,10 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
+	c.SetBackground(common.Black)
 	c.FillBackground()
-	c.SetColorSchema(generativeart.DarkRed)
-	c.SetForeground(generativeart.LightPink)
+	c.SetColorSchema(common.DarkRed)
+	c.SetForeground(common.LightPink)
 	c.Draw(generativeart.NewJanus(10, 0.2))
 	c.ToPNG("janus.png")
 }
diff --git a/example/example_julia.go b/example/example_julia.go
index 7454e7f..89828a3 100644
--- a/example/example_julia.go
+++ b/example/example_julia.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -18,7 +19,7 @@ func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
 	c.SetIterations(800)
-	c.SetColorSchema(generativeart.Viridis)
+	c.SetColorSchema(common.Viridis)
 	c.FillBackground()
 	c.Draw(generativeart.NewJulia(julia1, 40, 1.5, 1.5))
 	c.ToPNG("julia.png")
diff --git a/example/example_maze.go b/example/example_maze.go
index 2e11b74..b55f51f 100644
--- a/example/example_maze.go
+++ b/example/example_maze.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,9 +10,9 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(600, 600)
-	c.SetBackground(generativeart.Azure)
+	c.SetBackground(common.Azure)
 	c.SetLineWidth(3)
-	c.SetLineColor(generativeart.Orange)
+	c.SetLineColor(common.Orange)
 	c.FillBackground()
 	c.Draw(generativeart.NewMaze(20))
 	c.ToPNG("maze.png")
diff --git a/example/example_pixelhole.go b/example/example_pixelhole.go
new file mode 100644
index 0000000..c6ee556
--- /dev/null
+++ b/example/example_pixelhole.go
@@ -0,0 +1,28 @@
+package main
+
+import (
+	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
+	"image/color"
+	"math/rand"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().Unix())
+	colors := []color.RGBA{
+		{0xF9, 0xC8, 0x0E, 0xFF},
+		{0xF8, 0x66, 0x24, 0xFF},
+		{0xEA, 0x35, 0x46, 0xFF},
+		{0x66, 0x2E, 0x9B, 0xFF},
+		{0x43, 0xBC, 0xCD, 0xFF},
+	}
+	c := generativeart.NewCanva(800, 800)
+	c.SetBackground(common.Black)
+	c.FillBackground()
+	c.SetColorSchema(colors)
+	c.SetIterations(1200)
+	c.Draw(generativeart.NewPixelHole(60))
+	c.ToPNG("pixelhole.png")
+
+}
diff --git a/example/example_pointribbon.go b/example/example_pointribbon.go
index 3964ec6..bbb85e8 100644
--- a/example/example_pointribbon.go
+++ b/example/example_pointribbon.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,7 +10,7 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Lavender)
+	c.SetBackground(common.Lavender)
 	c.SetLineWidth(2)
 	c.SetIterations(150000)
 	c.FillBackground()
diff --git a/example/example_randcircle.go b/example/example_randcircle.go
index 45b4217..58bb826 100644
--- a/example/example_randcircle.go
+++ b/example/example_randcircle.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -10,7 +11,7 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.MistyRose)
+	c.SetBackground(common.MistyRose)
 	c.SetLineWidth(1.0)
 	c.SetLineColor(color.RGBA{
 		R: 122,
@@ -18,7 +19,7 @@ func main() {
 		B: 122,
 		A: 30,
 	})
-	c.SetColorSchema(generativeart.Plasma)
+	c.SetColorSchema(common.Plasma)
 	c.SetIterations(4)
 	c.FillBackground()
 	c.Draw(generativeart.NewRandCicle(30, 80, 0.2, 2, 10, 30, true))
diff --git a/example/example_randomshape.go b/example/example_randomshape.go
index df81d2e..0a0a5d5 100644
--- a/example/example_randomshape.go
+++ b/example/example_randomshape.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -10,7 +11,7 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.White)
+	c.SetBackground(common.White)
 	c.FillBackground()
 	c.SetColorSchema([]color.RGBA{
 		{0xCF, 0x2B, 0x34, 0xFF},
diff --git a/example/example_silksmoke.go b/example/example_silksmoke.go
index 13200c9..14b4f76 100644
--- a/example/example_silksmoke.go
+++ b/example/example_silksmoke.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,11 +10,11 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.Black)
+	c.SetBackground(common.Black)
 	c.SetLineWidth(1.0)
-	c.SetLineColor(generativeart.MediumAquamarine)
+	c.SetLineColor(common.MediumAquamarine)
 	c.SetAlpha(30)
-	c.SetColorSchema(generativeart.Plasma)
+	c.SetColorSchema(common.Plasma)
 	c.SetIterations(4)
 	c.FillBackground()
 	c.Draw(generativeart.NewSilkSmoke(400, 20, 0.2, 2, 10, 30, false))
diff --git a/example/example_spiralsquare.go b/example/example_spiralsquare.go
index 44f9e4d..182c15e 100644
--- a/example/example_spiralsquare.go
+++ b/example/example_spiralsquare.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"math/rand"
 	"time"
 )
@@ -9,11 +10,11 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
-	c.SetBackground(generativeart.MistyRose)
+	c.SetBackground(common.MistyRose)
 	c.SetLineWidth(10)
-	c.SetLineColor(generativeart.Orange)
-	c.SetColorSchema(generativeart.Plasma)
-	c.SetForeground(generativeart.Tomato)
+	c.SetLineColor(common.Orange)
+	c.SetColorSchema(common.Plasma)
+	c.SetForeground(common.Tomato)
 	c.FillBackground()
 	c.Draw(generativeart.NewSpiralSquare(40, 400, 0.05, true))
 	c.ToPNG("spiralsquare.png")
diff --git a/example/example_swirl.go b/example/example_swirl.go
index 02cbc69..f5a09ba 100644
--- a/example/example_swirl.go
+++ b/example/example_swirl.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
 	"image/color"
 	"math/rand"
 	"time"
@@ -10,7 +11,7 @@ import (
 func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(1600, 1600)
-	c.SetBackground(generativeart.Azure)
+	c.SetBackground(common.Azure)
 	c.FillBackground()
 	c.SetForeground(color.RGBA{113, 3, 0, 140})
 	c.SetIterations(4000000)
diff --git a/generativeart.go b/generativeart.go
index 4074a6d..85f47c7 100644
--- a/generativeart.go
+++ b/generativeart.go
@@ -1,6 +1,7 @@
 package generativeart
 
 import (
+	"github.com/jdxyw/generativeart/common"
 	"image"
 	"image/color"
 	"image/draw"
@@ -37,11 +38,11 @@ func NewCanva(h, w int) *canva {
 		img:    image.NewRGBA(image.Rect(0, 0, h, w)),
 		// Set some defaults value
 		opts: Options{
-			background:  Azure,
-			foreground:  MistyRose,
-			lineColor:   Tomato,
+			background:  common.Azure,
+			foreground:  common.MistyRose,
+			lineColor:   common.Tomato,
 			lineWidth:   3,
-			colorSchema: Plasma,
+			colorSchema: common.Plasma,
 			nIters:      20,
 			alpha:       255,
 		},
diff --git a/images/pixelhole.png b/images/pixelhole.png
new file mode 100644
index 0000000..f6de036
Binary files /dev/null and b/images/pixelhole.png differ
diff --git a/noiseline.go b/noiseline.go
index ac1b1e8..c628acb 100644
--- a/noiseline.go
+++ b/noiseline.go
@@ -23,7 +23,7 @@ func (nl *noiseLine) Generative(c *canva) {
 	ctex := gg.NewContextForRGBA(c.img)
 	noise := common.NewPerlinNoise()
 
-	ctex.SetColor(Black)
+	ctex.SetColor(common.Black)
 	for i := 0; i < 80; i++ {
 		x := rand.Float64() * float64(c.width)
 		y := rand.Float64() * float64(c.height)
diff --git a/pixelhole.go b/pixelhole.go
new file mode 100644
index 0000000..2761b03
--- /dev/null
+++ b/pixelhole.go
@@ -0,0 +1,55 @@
+package generativeart
+
+import (
+	"github.com/fogleman/gg"
+	"github.com/jdxyw/generativeart/common"
+	"math"
+	"math/rand"
+)
+
+type pixelHole struct {
+	dotN  int
+	noise *common.PerlinNoise
+}
+
+// NewPixelHole returns a pixelHole object.
+func NewPixelHole(dotN int) *pixelHole {
+	return &pixelHole{
+		dotN:  dotN,
+		noise: common.NewPerlinNoise(),
+	}
+}
+
+// Generative draws a pixel hole images.
+func (p *pixelHole) Generative(c *canva) {
+	ctex := gg.NewContextForRGBA(c.img)
+	//ctex.Translate(float64(c.width)/2, float64(c.height)/2)
+	for i := 0.0; i < float64(c.opts.nIters); i += 1.0 {
+		ctex.Push()
+		ctex.Translate(float64(c.width)/2, float64(c.height)/2)
+		p.draw(ctex, c, i)
+		ctex.Pop()
+	}
+}
+
+func (p *pixelHole) draw(ctex *gg.Context, c *canva, frameCount float64) {
+	ctex.SetLineWidth(2.0)
+	c1 := int(frameCount/100.0) % len(c.opts.colorSchema)
+	c2 := (int(frameCount/100.0) + 1) % len(c.opts.colorSchema)
+	ratio := frameCount/100 - math.Floor(frameCount/100)
+	cl := common.LerpColor(c.opts.colorSchema[c1], c.opts.colorSchema[c2], ratio)
+	for i := 0.0; i < float64(p.dotN); i += 1.0 {
+		ctex.Push()
+		ctex.SetColor(cl)
+		ctex.Rotate(frameCount/(50+10*math.Log(frameCount+1)) + i/20)
+		dd := frameCount/(5+i) + frameCount/5 + math.Sin(i)*50
+		ctex.Translate(common.RandomRangeFloat64(dd/2, dd), 0)
+		x := p.noise.Noise2D(frameCount/50+i/50, 5000)*float64(c.width)/10 + rand.Float64()*float64(c.width)/20
+		y := p.noise.Noise2D(frameCount/50+i/50, 10000)*float64(c.height)/10 + rand.Float64()*float64(c.height)/20
+
+		rr := common.RandomRangeFloat64(1.0, 6-math.Log(frameCount+1)/10)
+		ctex.DrawEllipse(x, y, rr, rr)
+		ctex.Fill()
+		ctex.Pop()
+	}
+}