vertical flags

bloat.go

@@ -31,11 +31,19 @@ func bloat_showflag(writer http.ResponseWriter, req *http.Request) {
 	code := mux.Vars(req)["code"]
 	colors := strings.Split(code, ",")
 	numcolors := len(colors)
-	h := (128 / numcolors) * numcolors
-	w := h * 3 / 2
-	img := image.NewRGBA(image.Rect(0, 0, w, h))
-	for i := 0; i < h; i++ {
-		hex := colors[i*numcolors/h]
+	vert := false
+	if colors[0] == "vert" {
+		vert = true
+		colors = colors[1:]
+		numcolors--
+		if numcolors == 0 {
+			http.Error(writer, "bad flag", 400)
+			return
+		}
+	}
+	pixels := make([][4]byte, numcolors)
+	for i := 0; i < numcolors; i++ {
+		hex := colors[i]
 		if len(hex) == 3 {
 			hex = fmt.Sprintf("%c%c%c%c%c%c",
 				hex[0], hex[0], hex[1], hex[1], hex[2], hex[2])
@@ -44,14 +52,33 @@ func bloat_showflag(writer http.ResponseWriter, req *http.Request) {
 		r := byte(c >> 16 & 0xff)
 		g := byte(c >> 8 & 0xff)
 		b := byte(c >> 0 & 0xff)
+		pixels[i][0] = r
+		pixels[i][1] = g
+		pixels[i][2] = b
+		pixels[i][3] = 255
+	}
+
+	h := 128
+	w := h * 3 / 2
+	img := image.NewRGBA(image.Rect(0, 0, w, h))
+	if vert {
+		for j := 0; j < w; j++ {
+			pix := pixels[j*numcolors/w][:]
+			for i := 0; i < h; i++ {
+				p := i*img.Stride + j*4
+				copy(img.Pix[p:], pix)
+			}
+		}
+	} else {
+		for i := 0; i < h; i++ {
+			pix := pixels[i*numcolors/h][:]
 			for j := 0; j < w; j++ {
 				p := i*img.Stride + j*4
-			img.Pix[p+0] = r
-			img.Pix[p+1] = g
-			img.Pix[p+2] = b
-			img.Pix[p+3] = 255
+				copy(img.Pix[p:], pix)
 			}
 		}
+	}
+
 	writer.Header().Set("Cache-Control", "max-age="+somedays())
 	png.Encode(writer, img)
 }