add color canva

README.md

@@ -31,6 +31,7 @@
     - [Ocean Fish](#ocean-fish)
     - [Circle Loop](#circle-loop)
     - [Circle Noise](#circle-noise)
+    - [Color Canva](#color-canva)
     - [Julia Set](#julia-set)
     - [Black Hole](#black-hole)
     - [Silk Sky](#silk-sky)
@@ -424,6 +425,30 @@ func main() {
 
 ![](images/circlenoise.png)
 
+### Color Canva
+
+```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(common.Black)
+ c.FillBackground()
+ c.SetLineWidth(8)
+ c.SetColorSchema(colors)
+ c.Draw(arts.NewColorCanve(5))
+ c.ToPNG("colorcanva.png")
+}
+```
+
+![](images/colorcanva.png)
+
 ### Julia Set
 
 ```go

arts/colorcanva.go

@@ -0,0 +1,66 @@
+package arts
+
+import (
+	"github.com/fogleman/gg"
+	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/common"
+	"math/rand"
+)
+
+type colorCanva struct {
+	seg float64
+}
+
+func NewColorCanve(seg float64) *colorCanva {
+	return &colorCanva{seg: seg}
+}
+
+// Generative returns a color canva image.
+func (cc *colorCanva) Generative(c *generativeart.Canva) {
+	ctex := gg.NewContextForRGBA(c.Img())
+	ctex.SetLineWidth(c.Opts().LineWidth())
+
+	rects := make([]*common.Rect, 0)
+	w := float64(c.Width()) / cc.seg
+	for i := 0.0; i < cc.seg; i += 1.0 {
+		for j := 0.0; j < cc.seg; j += 1.0 {
+			x := i*w + w/2
+			y := j*w + w/2
+			rects = append(rects, common.NewRect(x, y, w, w))
+		}
+	}
+
+	rand.Shuffle(len(rects), func(i, j int) {
+		rects[i], rects[j] = rects[j], rects[i]
+	})
+
+	ctex.Translate(float64(c.Width())/2, float64(c.Height())/2)
+	ctex.Scale(0.6, 0.6)
+	ctex.Translate(-float64(c.Width())/2, -float64(c.Height())/2)
+
+	for i := 0; i < len(rects); i++ {
+		cc.draw(c, ctex, rects[i])
+		cc.draw(c, ctex, rects[i])
+	}
+}
+
+func (cc *colorCanva) draw(c *generativeart.Canva, ctex *gg.Context, rect *common.Rect) {
+	rnd := rand.Intn(4)
+	ww := (rect.W() / 5) * float64(rand.Intn(int(cc.seg)*2)+1)
+	hh := (rect.H() / 5) * float64(rand.Intn(int(cc.seg)*2)+1)
+
+	switch rnd {
+	case 0:
+		ctex.DrawRectangle(rect.X()-ww/2+rect.W()/2, rect.Y()+hh/2+rect.H()/2, ww, hh)
+	case 1:
+		ctex.DrawRectangle(rect.X()-ww/2-rect.W()/2, rect.Y()+hh/2+rect.H()/2, ww, hh)
+	case 2:
+		ctex.DrawRectangle(rect.X()-ww/2+rect.W()/2, rect.Y()+hh/2-rect.H()/2, ww, hh)
+	case 3:
+		ctex.DrawRectangle(rect.X()-ww/2-rect.W()/2, rect.Y()+hh/2-rect.H()/2, ww, hh)
+	}
+	ctex.SetColor(common.Black)
+	ctex.StrokePreserve()
+	ctex.SetColor(c.Opts().ColorSchema()[rand.Intn(len(c.Opts().ColorSchema()))])
+	ctex.Fill()
+}

common/rect.go

@@ -0,0 +1,30 @@
+package common
+
+type Rect struct {
+	x, y, w, h float64
+}
+
+func (r Rect) X() float64 {
+	return r.x
+}
+
+func (r Rect) Y() float64 {
+	return r.y
+}
+
+func (r Rect) W() float64 {
+	return r.w
+}
+
+func (r Rect) H() float64 {
+	return r.h
+}
+
+func NewRect(x, y, w, h float64) *Rect {
+	return &Rect{
+		x: x,
+		y: y,
+		w: w,
+		h: h,
+	}
+}

docs/doc.md

@@ -34,6 +34,9 @@
 		- [parameters](#parameters-14)
 	- [Black Hole](#black-hole)
 		- [parameters](#parameters-15)
+	- [Color Canva](#color-canva)
+		- [parameters](#parameters-16)
+
 ## Color Circle 2
 
 `Color Circle2` is version 2 of `Color Circle`. It still draws the circle and point cloud.
@@ -95,9 +98,10 @@ rs := NewRandomShape(150)
 - lineNum: It indicates how many lines.
 
 ![](../images/contourline.png)
+
 ## Silk Sky
 
-`Silk Sky` would draw an image with multiple circles converge to one point or one circle. 
+`Silk Sky` would draw an image with multiple circles converge to one point or one circle.
 
 ### parameters
 
@@ -122,9 +126,9 @@ silkSky := NewSilkSky(circleNum int, sunRadius float64)
 
 ```go
 func julia1(z complex128) complex128 {
-	c := complex(-0.1, 0.651)
-	z = z*z + c
-	return z
+ c := complex(-0.1, 0.651)
+ z = z*z + c
+ return z
 }
 julia := arts.NewJulia(julia1, 40, 1.5, 1.5)
 ```
@@ -206,7 +210,6 @@ d := arts.NewDotsWave(300)
 
 - circleNum: The number of the circle in the image.
 
-
 ```go
 cm := arts.NewCircleMove(1000)
 ```
@@ -247,4 +250,16 @@ y := arts.NewYarn(2000)
 b := arts.NewBlackHole(200, 400, 0.01)
 ```
 
-![](../images/blackhole.png)
+![](../images/blackhole.png)
+
+## Color Canva
+
+### parameters
+
+- seg:
+
+```go
+cc := arts.NewColorCanve(5)
+```
+
+![](../images/colorcanva.png)

example/example_colorcanva.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"github.com/jdxyw/generativeart"
+	"github.com/jdxyw/generativeart/arts"
+	"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(500, 500)
+	c.SetBackground(common.Black)
+	c.FillBackground()
+	c.SetLineWidth(8)
+	c.SetColorSchema(colors)
+	c.Draw(arts.NewColorCanve(5))
+	c.ToPNG("colorcanva.png")
+}