cmd

cmd/showpalette/show.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"encoding/csv"
+	"image"
+	"image/color"
+	"image/png"
+	"math"
+	"os"
+
+	imgutil "git.niplace.ru/XoxJlopeZi4BB/imageutils/pkg"
+)
+
+func nearestHighSqrt(n int) int {
+	if math.Mod(math.Sqrt(float64(n)), 1) == 0 {
+		return n
+	}
+	return nearestHighSqrt(n + 1)
+}
+
+type showColors struct {
+	color.Palette
+}
+
+func (s showColors) ColorModel() color.Model {
+	return color.RGBAModel
+}
+
+func (s showColors) Bounds() image.Rectangle {
+	n := nearestHighSqrt(len(s.Palette))
+	return image.Rect(0, 0, n, n)
+}
+
+func (s showColors) At(x, y int) color.Color {
+	n := nearestHighSqrt(len(s.Palette))
+	return s.Palette[y*n+x]
+}
+
+func check(err error) {
+	if err != nil {
+		panic(err)
+	}
+}
+
+func Must[T any](v T, err error) T {
+	check(err)
+	return v
+}
+
+func Map[S1 ~[]T1, S2 ~[]T2, T1, T2 any](s S1, f func(T1) T2) S2 {
+	result := make(S2, len(s))
+	for i := range s {
+		result[i] = f(s[i])
+	}
+	return result
+}
+
+func main() {
+	r := csv.NewReader(os.Stdin)
+	r.TrailingComma = true
+	colors, err := r.Read()
+	check(err)
+	palette := color.Palette(
+		Map[[]string, color.Palette](colors,
+			func(v string) color.Color {
+				println(v + "cat-v")
+				return Must(imgutil.ParseHexColor(v))
+			},
+		),
+	)
+	
+	err = png.Encode(os.Stdout, showColors{palette})
+	check(err)
+}