status-go/protocol/identity/identicon/renderer.go

74 lines
1.4 KiB
Go

package identicon
import (
"bytes"
"encoding/base64"
"image"
"image/color"
"image/draw"
"image/png"
)
const (
Width = 50
Height = 50
)
func renderBase64(id Identicon) (string, error) {
img, err := render(id)
if err != nil {
return "", err
}
encodedString := base64.StdEncoding.EncodeToString(img)
image := "data:image/png;base64," + encodedString
return image, nil
}
func setBackgroundTransparent(img *image.RGBA) {
draw.Draw(img, img.Bounds(), &image.Uniform{C: color.Transparent}, image.Point{}, draw.Src)
}
func drawRect(rgba *image.RGBA, i int, c color.Color) {
sizeSquare := 6
maxRow := 5
r := image.Rect(
10+(i%maxRow)*sizeSquare,
10+(i/maxRow)*sizeSquare,
10+(i%maxRow)*sizeSquare+sizeSquare,
10+(i/maxRow)*sizeSquare+sizeSquare,
)
draw.Draw(rgba, r, &image.Uniform{C: c}, image.Point{}, draw.Src)
}
func render(id Identicon) ([]byte, error) {
img := image.NewRGBA(image.Rect(0, 0, Width, Height))
var buff bytes.Buffer
setBackgroundTransparent(img)
for i, v := range id.bitmap {
if v == 1 {
drawRect(img, i, id.color)
}
}
if err := png.Encode(&buff, img); err != nil {
return nil, err
}
return buff.Bytes(), nil
}
// GenerateBase64 generates an identicon in base64 png format given a string
func GenerateBase64(id string) (string, error) {
i := generate(id)
return renderBase64(i)
}
func Generate(id string) ([]byte, error) {
i := generate(id)
return render(i)
}