Print colors map in Output216 mode of termbox-go

print_216_colors.go

package main

import (
	"fmt"
	"strconv"
	"strings"

	termbox "github.com/nsf/termbox-go"
)

func main() {
	if err := termbox.Init(); err != nil {
		panic(err)
	}
	defer termbox.Close()
	termbox.SetOutputMode(termbox.Output216)

	for y := 0; y < 6; y++ {
		for x := 1; x <= 36; x++ {
			var fg termbox.Attribute
			if x <= 18 {
				fg = 216
			} else {
				fg = 1
			}

			code := y*36 + x
			codeStr := rightPad(strconv.Itoa(code), 3)
			for i, r := range codeStr {
				termbox.SetCell((x-1)*3+i, y, r, fg, termbox.Attribute(code))
			}
		}
	}

	termbox.Flush()

	var c byte
	fmt.Scan(&c)
}

func rightPad(s string, n int) string {
	return s + strings.Repeat(" ", n-len(s))
}

print_216_colors.png