diff options
Diffstat (limited to 'label-exp/main.go')
| -rw-r--r-- | label-exp/main.go | 66 |
1 files changed, 64 insertions, 2 deletions
diff --git a/label-exp/main.go b/label-exp/main.go index 3280733..b530f2f 100644 --- a/label-exp/main.go +++ b/label-exp/main.go @@ -49,6 +49,28 @@ func (s *scaler) At(x, y int) color.Color { return s.image.At(x/s.scale, y/s.scale) } +// leftRotate is a 90 degree rotating image.Image wrapper. +type leftRotate struct { + image image.Image +} + +// ColorModel implements image.Image. +func (lr *leftRotate) ColorModel() color.Model { + return lr.image.ColorModel() +} + +// Bounds implements image.Image. +func (lr *leftRotate) Bounds() image.Rectangle { + r := lr.image.Bounds() + // Min is inclusive, Max is exclusive. + return image.Rect(r.Min.Y, -(r.Max.X - 1), r.Max.Y, -(r.Min.X - 1)) +} + +// At implements image.Image. +func (lr *leftRotate) At(x, y int) color.Color { + return lr.image.At(-y, x) +} + // ----------------------------------------------------------------------------- func decodeBitfieldErrors(b byte, errors [8]string) []string { @@ -289,11 +311,10 @@ func printLabel(src image.Image) error { var font *bdf.Font -// TODO: By rotating the label we can make it smaller, as an alternate mode. func genLabel(text string, width int) image.Image { // Create a scaled bitmap of the QR code. qrImg, _ := qr.Encode(text, qr.H, qr.Auto) - qrImg, _ = barcode.Scale(qrImg, 306, 306) + qrImg, _ = barcode.Scale(qrImg, width, width) qrRect := qrImg.Bounds() // Create a scaled bitmap of the text label. @@ -321,6 +342,45 @@ func genLabel(text string, width int) image.Image { return combinedImg } +func genLabelForHeight(text string, height 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) + + // TODO: Make it possible to choose scale, or use some heuristic. + scaledTextImg := scaler{image: textImg, scale: 3} + //scaledTextImg := scaler{image: textImg, scale: 3} + 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 +} + var tmpl = template.Must(template.New("form").Parse(` <!DOCTYPE html> <html><body> @@ -361,7 +421,9 @@ func handle(w http.ResponseWriter, r *http.Request) { params.Width = 306 // Default to 29mm tape. } + // TODO: Possibly just remove the for-width mode. label := genLabel(params.Text, params.Width) + label = &leftRotate{image: genLabelForHeight(params.Text, params.Width)} if r.FormValue("print") != "" { if err := printLabel(label); err != nil { log.Println("print error:", err) |