View Calculator Image Art of Christoph Giesselink

artwork.go

// Command artwork converts the ARTWORK of a talented artist Christoph Giesselink
// to machine readable format.
//
// Artwork location: https://hp.giesselink.com/ImageArt/ImageArt.htm

/*
This program is free software: you can redistribute it and/or modify it under the terms
of the GNU General Public License as published by the Free Software Foundation,
either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this
program. If not, see <https://www.gnu.org/licenses/>.
*/

package main

import (
	"flag"
	"fmt"
	"image"
	"image/png"
	"log"
	"os"
	"path/filepath"
)

var (
	input  = flag.String("i", "hp17bii.png", "input image")
	output = flag.String("o", "", "output file")
)

func swapExt(s string, ext string) string {
	return s[:len(s)-len(filepath.Ext(s))] + ext
}

func main() {
	flag.Parse()

	if *input == "" {
		log.Fatal("no input artwork specified")
	}
	if *output == "" {
		*output = swapExt(*input, ".rom")
	}
	if err := convert(*input, *output); err != nil {
		log.Fatal(err)
	}
}

func convert(pngIn string, romOut string) error {
	f, err := os.Open(pngIn)
	if err != nil {
		return fmt.Errorf("error opening artwork: %w", err)
	}
	defer f.Close()
	iimg, err := png.Decode(f)
	if err != nil {
		return fmt.Errorf("error loading artwork: %w", err)
	}
	img, ok := iimg.(*image.Paletted)
	if !ok {
		return fmt.Errorf("invalid artwork type: %T", img)
	}
	if err := os.WriteFile(romOut, img.Pix, 0644); err != nil {
		return fmt.Errorf("error writing output file: %w", err)
	}
	return nil
}

go.mod

module github.com/rusq/hpromread

go 1.22.2

go.sum