Lambda Art

lambdaArt.go

package main

import (
  "image"
  "image/color"
  "image/png"
  "math"
  "os"
)

type expr func(x,y float64) (r,g,b float64)

func toByte(x float64) uint8 {
  return uint8(math.Max(0.0, math.Min(255.0, 128.0*(x+1.0))))
}

func createImage(width int, height int, e expr) image.Image {
  img := image.NewRGBA(image.Rect(0, 0, width, height))
  for y := 0; y < height; y++ {
    for x := 0; x < width; x++ {
      u := (float64(x-width/2)+0.5)/float64(width)
      v := (float64(y-height/2)+0.5)/float64(height)
      r, g, b := e(u, v)
      c := color.RGBA{toByte(r), toByte(g), toByte(b), 255}
      img.SetRGBA(x, y, c)
    }
  }
  return img
}

func main() {
  out, _ := os.Create("./output.png")
  defer out.Close()
  e := func(x,y float64) (r,g,b float64) {
    r = math.Sin(y)
    g = math.Sin(x)
    b = x * y
    return
  }
  img := createImage(640, 480, e)
  png.Encode(out, img)
}