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package label
import (
"image"
"image/color"
"image/draw"
"strings"
"janouch.name/sklad/bdf"
"janouch.name/sklad/imgutil"
"github.com/boombuler/barcode"
"github.com/boombuler/barcode/qr"
)
// TODO: Rename to GenQRLabelForHeight.
func GenLabelForHeight(font *bdf.Font,
text string, height, scale int) image.Image {
// Create a scaled bitmap of the text label.
textRect, _ := font.BoundString(text)
textImg := image.NewRGBA(textRect)
draw.Draw(textImg, textRect, image.White, image.ZP, draw.Src)
font.DrawString(textImg, image.ZP, color.Black, text)
scaledTextImg := imgutil.Scale{Image: textImg, Scale: scale}
scaledTextRect := scaledTextImg.Bounds()
remains := height - scaledTextRect.Dy() - 20
width := scaledTextRect.Dx()
if remains > width {
width = remains
}
// Create a scaled bitmap of the QR code.
qrImg, _ := qr.Encode(text, qr.H, qr.Auto)
qrImg, _ = barcode.Scale(qrImg, remains, remains)
qrRect := qrImg.Bounds()
// Combine.
combinedRect := image.Rect(0, 0, width, height)
combinedImg := image.NewRGBA(combinedRect)
draw.Draw(combinedImg, combinedRect, image.White, image.ZP, draw.Src)
draw.Draw(combinedImg,
combinedRect.Add(image.Point{X: (width - qrRect.Dx()) / 2, Y: 0}),
qrImg, image.ZP, draw.Src)
target := image.Rect(
(width-scaledTextRect.Dx())/2, qrRect.Dy()+20,
combinedRect.Max.X, combinedRect.Max.Y)
draw.Draw(combinedImg, target, &scaledTextImg, scaledTextRect.Min, draw.Src)
return combinedImg
}
func max(a, b int) int {
if a > b {
return a
}
return b
}
func GenLabelForWidth(font *bdf.Font,
text string, width, scale int) image.Image {
var lines []string
for _, line := range strings.Split(text, "\n") {
lines = append(lines, strings.TrimSuffix(line, "\r"))
}
// Respect font ascent and descent so that there are gaps between lines.
rects := make([]image.Rectangle, len(lines))
jumps := make([]int, len(lines))
for i, line := range lines {
r, _ := font.BoundString(line)
rects[i] = r
if i > 0 {
deficitD := font.Descent - rects[i-1].Max.Y
jumps[i] += max(0, deficitD)
deficitA := font.Ascent - (-r.Min.Y)
jumps[i] += max(0, deficitA)
}
}
height := 0
for i := range lines {
height += jumps[i] + rects[i].Dy()
}
imgRect := image.Rect(0, 0, width, height*scale)
img := image.NewRGBA(imgRect)
draw.Draw(img, imgRect, image.White, image.ZP, draw.Src)
y := 0
for i, line := range lines {
textImg := image.NewRGBA(rects[i])
draw.Draw(textImg, rects[i], image.White, image.ZP, draw.Src)
font.DrawString(textImg, image.ZP, color.Black, line)
scaledImg := imgutil.Scale{Image: textImg, Scale: scale}
scaledRect := scaledImg.Bounds()
y += jumps[i]
target := image.Rect(0, y*scale, imgRect.Max.X, imgRect.Max.Y)
draw.Draw(img, target, &scaledImg, scaledRect.Min, draw.Src)
y += rects[i].Dy()
}
return img
}
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