package main import ( "bytes" "fmt" "io/ioutil" "github.com/muesli/clusters" "github.com/muesli/kmeans" "github.com/muesli/kmeans/plotter" colorful "github.com/lucasb-eyer/go-colorful" ) var ( header = ` ` cell = `

` footer = `

` ) type Color struct { colorful.Color } func (c Color) Coordinates() clusters.Coordinates { l, a, b := c.Lab() return clusters.Coordinates{l, a, b} } func (c Color) Distance(pos clusters.Coordinates) float64 { c2 := colorful.Lab(pos[0], pos[1], pos[2]) return c.DistanceLab(c2) } func main() { // Create data points in the CIE L*a*b color space // l for lightness channel // a, b for color channels var d clusters.Observations for l := 0.2; l < 0.8; l += 0.05 { for a := -1.0; a < 1.0; a += 0.1 { for b := -1.0; b < 1.0; b += 0.1 { c := colorful.Lab(l, a, b) if !c.IsValid() { continue } d = append(d, Color{c}) } } } // Write HTML header buffer := bytes.NewBuffer([]byte{}) buffer.Write([]byte(header)) // Enable graph generation (.png files) for each iteration km, _ := kmeans.NewWithOptions(0.01, plotter.SimplePlotter{}) // Partition the color space into 16 clusters (palette colors) clusters, _ := km.Partition(d, 16) for i, c := range clusters { fmt.Printf("Cluster: %d %+v\n", i, c.Center) col := colorful.Lab(c.Center[0], c.Center[1], c.Center[2]).Clamped() fmt.Println("Color as Hex:", col.Hex()) buffer.Write([]byte(fmt.Sprintf(cell, col.Hex()))) } // Write HTML footer and generate palette.html buffer.Write([]byte(footer)) ioutil.WriteFile("palette.html", buffer.Bytes(), 0644) }