svgpng.go

package main

import (
	"bufio"
	"fmt"
	"image"
	"image/color"
	"image/png"
	"os"

	"github.com/srwiley/oksvg"
	"github.com/srwiley/rasterx"
)

func DrawIcon(iconPath string) image.Image {
	icon, errSvg := oksvg.ReadIcon(iconPath, oksvg.IgnoreErrorMode)
	if errSvg != nil {
		return nil
	}
	w, h := int(icon.ViewBox.W), int(icon.ViewBox.H)
	img := image.NewRGBA(image.Rect(0, 0, w, h))

	source := image.NewUniform(color.NRGBA{0, 0, 0, 255})
	scannerGV := rasterx.NewScannerGV(w, h, img, img.Bounds(), source, image.Point{0, 0})
	raster := rasterx.NewDasher(w, h, scannerGV)

	icon.Draw(raster, 1.0)
	return img
}

func SaveIcon(iconPath string) error {
	var err error
	img := DrawIcon(iconPath)
	if img != nil {
		err = SaveToPngFile(fmt.Sprintf("%s.png", iconPath), img)
		if err != nil {
			return err
		}
	}
	return err
}

func SaveToPngFile(filePath string, m image.Image) error {
	// Create the file
	f, err := os.Create(filePath)
	if err != nil {
		return err
	}
	defer f.Close()
	// Create Writer from file
	b := bufio.NewWriter(f)
	// Write the image into the buffer
	err = png.Encode(b, m)
	if err != nil {
		return err
	}
	err = b.Flush()
	if err != nil {
		return err
	}
	return nil
}

func main() {
	for _, f := range os.Args[1:] {
		err := SaveIcon(f)
		if err != nil {
			fmt.Printf("%v\n", err)
			continue
		}
	}
}