My answer for http://go-tour-jp.appspot.com/#35

gistfile1.go

package main

import "code.google.com/p/go-tour/pic"

func Pic(dx, dy int) [][]uint8 {
    pic := make([][]uint8, dy)
    for y := 0; y < dy; y++ {
        pic[y] = make([]uint8, dx)
    }
    for y, pr := range pic {
        for x := range pr {
    		pr[x] = uint8(x*y)
        }
    }
    return pic
    
}

func main() {
    pic.Show(Pic)
}