add label to *Image.RGBA golang

labeltorgba.go

package labeltorgba

import (
  "image"
  "github.com/golang/freetype"
	"github.com/golang/freetype/truetype"
)

func addLabel(text string, canvas **image.RGBA, centerX int, centerY int, fontSize int, fontPath string) {
	fontBytes, err := os.ReadFile(fontPath)
	if err != nil {
		log.Fatal(err)
	}
	font, err := truetype.Parse(fontBytes)
	if err != nil {
		log.Fatal(err)
	}
	ctx := freetype.NewContext()
	ctx.SetDPI(72)
	ctx.SetFont(font)
	ctx.SetFontSize(float64(fontSize))
	ctx.SetSrc(image.NewUniform(color.Transparent))
	ctx.SetDst(*canvas)
	ctx.SetClip((*canvas).Bounds())

	bounds, _ := ctx.DrawString(text, freetype.Pt(0, 0))

	ctx = freetype.NewContext()
	ctx.SetDPI(72)
	ctx.SetFont(font)
	ctx.SetFontSize(float64(fontSize))
	ctx.SetSrc(image.NewUniform(color.White))
	ctx.SetDst(*canvas)
	ctx.SetClip((*canvas).Bounds())

	x := centerX - bounds.X.Round()/2
	y := centerY - bounds.Y.Round()/2

	ctx.DrawString(text, freetype.Pt(x, y))
}