add perlin perls

README.md

@@ -33,6 +33,7 @@
     - [Circle Loop](#circle-loop)
     - [Domain Warp](#domain-warp)
     - [Circle Noise](#circle-noise)
+    - [Perlin Perls](#perlin-perls)
     - [Color Canva](#color-canva)
     - [Julia Set](#julia-set)
     - [Black Hole](#black-hole)
@@ -83,6 +84,7 @@ This package is still working in progress. More types would be added. Welcome an
 - Black Hole
 - Color Canva
 - Domain Warp
+- Perlin Perls
 
 For these kinds of art, the package provides as many parameters to control the appearance.
 
@@ -123,6 +125,7 @@ NewYarn(n int)
 NewBlackHole(circleN int, density, circleGap float64)
 NewColorCanve(seg float64)
 NewDomainWrap(scale, scale2, xOffset, yOffset float64, cmap ColorMapping)
+NewPerlinPerls(circleN, dotsN, colorMin, colorMax int)
 ```
 
 ## Docs
@@ -460,6 +463,24 @@ func main() {
 
 ![](images/circlenoise.png)
 
+### Perlin Perls
+
+```go
+func main() {
+ rand.Seed(time.Now().Unix())
+ c := generativeart.NewCanva(500, 500)
+ c.SetBackground(common.White)
+ c.SetAlpha(120)
+ c.SetLineWidth(0.3)
+ c.FillBackground()
+ c.SetIterations(200)
+ c.Draw(arts.NewPerlinPerls(10, 200, 40, 80))
+ c.ToPNG("perlinperls.png")
+}
+```
+
+![](../images/perlinperls.png)
+
 ### Color Canva
 
 ```go

arts/circlenoise.go

@@ -18,6 +18,7 @@ type dot struct {
 	prevx, prevy float64
 	theta        float64
 	count        int
+	cx, cy       float64
 }
 
 func NewCircleNoise(dotsN, colorMin, colorMax int) *circleNoise {

arts/perlinpearls.go

@@ -0,0 +1,123 @@
+package arts
+
+import (
+	"github.com/fogleman/gg"
+	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
+	"math"
+	"math/rand"
+)
+
+type perlinPearls struct {
+	circleN            int
+	dotsN              int
+	colorMin, colorMax int
+}
+
+type circles struct {
+	x, y               float64
+	radius             float64
+	colorMin, colorMax int
+}
+
+func NewPerlinPerls(circleN, dotsN, colorMin, colorMax int) *perlinPearls {
+	return &perlinPearls{
+		circleN:  circleN,
+		dotsN:    dotsN,
+		colorMin: colorMin,
+		colorMax: colorMax,
+	}
+}
+
+// Generative draws a circle with perlin noise.
+func (pp *perlinPearls) Generative(c *generativeart.Canva) {
+	ctex := gg.NewContextForRGBA(c.Img())
+	ctex.SetLineWidth(0.5)
+	ctex.SetColor(common.Black)
+
+	cs := make([]circles, 0)
+
+	for len(cs) < pp.circleN {
+		c := circles{
+			x:        common.RandomRangeFloat64(100, float64(c.Width())-50),
+			y:        common.RandomRangeFloat64(100, float64(c.Height())-50),
+			radius:   common.RandomRangeFloat64(20, 100),
+			colorMin: pp.colorMin,
+			colorMax: pp.colorMax,
+		}
+		var overlapping bool
+		for _, cl := range cs {
+			d := common.Distance(c.x, c.y, cl.x, cl.y)
+			if d < c.radius+cl.radius {
+				overlapping = true
+				break
+			}
+		}
+
+		if overlapping == false {
+			cs = append(cs, c)
+		}
+
+	}
+
+	ds := make([][]dot, 0)
+
+	for i := 0; i < pp.circleN; i++ {
+		dots := make([]dot, 0)
+		for j := 0; j < pp.dotsN; j++ {
+			theta := rand.Float64() * math.Pi * 2
+			//x, y := float64(c.Width())/2+math.Sin(theta)*radius, float64(c.Height())/2+math.Cos(theta)*radius
+			dots = append(dots, dot{
+				theta: theta,
+				cx:    cs[i].x,
+				cy:    cs[i].y,
+				x:     cs[i].x + math.Sin(theta)*cs[i].radius,
+				y:     cs[i].y + math.Cos(theta)*cs[i].radius,
+				prevx: cs[i].x + math.Sin(theta)*cs[i].radius,
+				prevy: cs[i].y + math.Cos(theta)*cs[i].radius,
+				count: 0,
+			})
+		}
+
+		ds = append(ds, dots)
+	}
+
+	noise := common.NewPerlinNoise()
+
+	for i := 0; i < pp.circleN; i++ {
+		ctex.SetLineWidth(0.5)
+		ctex.SetColor(common.Black)
+		ctex.DrawCircle(cs[i].x, cs[i].y, cs[i].radius)
+		ctex.Stroke()
+
+		var factor = 0.008
+		for j := 0; j < c.Opts().NIters(); j++ {
+			for k := range ds[i] {
+				n := noise.Noise2D(ds[i][k].x*factor, ds[i][k].y*factor)
+				nx, ny := math.Cos(n*math.Pi*2+float64(ds[i][k].count)*math.Pi)*2, math.Sin(n*math.Pi*2+float64(ds[i][k].count)*math.Pi)*2
+				ds[i][k].prevx, ds[i][k].prevy = ds[i][k].x, ds[i][k].y
+				ds[i][k].x, ds[i][k].y = ds[i][k].x+nx, ds[i][k].y+ny
+
+				hsv := common.HSV{
+					H: int(common.Remap(n, 0, 1, float64(cs[i].colorMin), float64(cs[i].colorMax))),
+					S: 100,
+					V: 20,
+				}
+
+				if common.Distance(cs[i].x, cs[i].y, ds[i][k].x, ds[i][k].y) > cs[i].radius+1 {
+					ds[i][k].count += 1
+				}
+
+				if common.Distance(cs[i].x, cs[i].y, ds[i][k].x, ds[i][k].y) < cs[i].radius &&
+					common.Distance(cs[i].x, cs[i].y, ds[i][k].prevx, ds[i][k].prevy) < cs[i].radius {
+					ctex.SetLineWidth(c.Opts().LineWidth())
+					rgb := hsv.ToRGB(100, 100, 100)
+					rgb.A = uint8(c.Opts().Alpha())
+					ctex.SetColor(rgb)
+					ctex.DrawLine(ds[i][k].prevx, ds[i][k].prevy, ds[i][k].x, ds[i][k].y)
+					ctex.Stroke()
+				}
+			}
+		}
+	}
+}

common/vector.go

@@ -15,3 +15,13 @@ func (v *Vector) Multiple(z float64) {
 	v.X = v.X * z
 	v.Y = v.Y * z
 }
+
+func (v *Vector) Normalize() {
+	l := Magnitude(v.X, v.Y)
+	v.Multiple(1 / l)
+}
+
+func (v *Vector) SetMag(m float64) {
+	v.Normalize()
+	v.Multiple(m)
+}

docs/doc.md

@@ -38,6 +38,8 @@
 		- [parameters](#parameters-16)
 	- [Domain Warping](#domain-warping)
 		- [parameters](#parameters-17)
+	- [Perlin Perls](#perlin-perls)
+		- [parameters](#parameters-18)
 
 ## Color Circle 2
 
@@ -282,3 +284,18 @@ d := arts.NewDomainWrap(0.01, 4, 8, cmap)
 ```
 
 ![](../images/domainwarp.png)
+
+## Perlin Perls
+
+### parameters
+
+- circleN: The number of circle on this image.
+- dotsN: The number of dots in each circle. 
+- colorMin: The minimum color.
+- colorMax: The maximum color.
+
+```go
+pp := arts.NewPerlinPerls(10, 200, 40, 80
+```
+
+![](../images/perlinperls.png)

example/example_circlenoise.go

@@ -12,7 +12,7 @@ func main() {
 	rand.Seed(time.Now().Unix())
 	c := generativeart.NewCanva(500, 500)
 	c.SetBackground(common.White)
-	c.SetAlpha(80)
+	c.SetAlpha(5)
 	c.SetLineWidth(0.3)
 	c.FillBackground()
 	c.SetIterations(400)

example/example_perlinpearls.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/arts"
+	"github.com/jdxyw/generativeart/common"
+	"math/rand"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().Unix())
+	c := generativeart.NewCanva(500, 500)
+	c.SetBackground(common.White)
+	c.SetAlpha(120)
+	c.SetLineWidth(0.3)
+	c.FillBackground()
+	c.SetIterations(200)
+	c.Draw(arts.NewPerlinPerls(10, 200, 40, 80))
+	c.ToPNG("perlinperls.png")
+}