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Diffstat (limited to 'label/label.go')
-rw-r--r--label/label.go87
1 files changed, 87 insertions, 0 deletions
diff --git a/label/label.go b/label/label.go
new file mode 100644
index 0000000..062b072
--- /dev/null
+++ b/label/label.go
@@ -0,0 +1,87 @@
+package label
+
+import (
+ "image"
+ "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, 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 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"))
+ }
+
+ height := 0
+ var rects []image.Rectangle
+ for _, line := range lines {
+ r, _ := font.BoundString(line)
+ rects = append(rects, r)
+ height += r.Dy() * scale
+ }
+
+ imgRect := image.Rect(0, 0, width, height)
+ img := image.NewRGBA(imgRect)
+ draw.Draw(img, imgRect, image.White, image.ZP, draw.Src)
+
+ y := 0
+ for i := 0; i < len(lines); i++ {
+ textImg := image.NewRGBA(rects[i])
+ draw.Draw(textImg, rects[i], image.White, image.ZP, draw.Src)
+ font.DrawString(textImg, image.ZP, lines[i])
+
+ scaledImg := imgutil.Scale{Image: textImg, Scale: scale}
+ scaledRect := scaledImg.Bounds()
+
+ target := image.Rect(0, y, imgRect.Max.X, imgRect.Max.Y)
+ draw.Draw(img, target, &scaledImg, scaledRect.Min, draw.Src)
+ y += scaledRect.Dy()
+ }
+ return img
+}