Add scaling functionality

README.md

@@ -118,12 +118,13 @@ curl -k --anyauth -u root:<password> \
 will list the current settings:
 
 ```sh
-root.findwind.FindwindSpotID=301
-root.findwind.Style=1A
-root.findwind.Opacity=0.7
-root.findwind.Position=topLeft
-root.findwind.CustomPositionX=0
-root.findwind.CustomPositionY=0
+root.Findwind.CustomPositionX=0
+root.Findwind.CustomPositionY=0
+root.Findwind.FindwindSpotID=301
+root.Findwind.Opacity=0.7
+root.Findwind.Position=topLeft
+root.Findwind.Scale=100
+root.Findwind.Style=1A
 ```
 
 > [!TIP]
@@ -137,13 +138,18 @@ root.findwind.CustomPositionY=0
 > *topLeft/topRight/bottomLeft/bottomRight/custom* and *CustomPositionX*
 > and *CustomPositionY* must be within the range -1.0 to 1.0.
 
-If you want to set the opacity to e.g. 0.8:
+If you want to set the style to e.g. 1B:
 
 ```sh
 curl -k --anyauth -u root:<password> \
-    'https://<camera hostname/ip>/axis-cgi/param.cgi?action=update&root.findwind.Opacity=0.8'
+    'https://<camera hostname/ip>/axis-cgi/param.cgi?action=update&root.findwind.Style=1B'
 ```
 
+> [!TIP]
+> The *Scale* parameter is a percentage value that scales the overlay size.
+> For example, a scale of 200 will double the size of the overlay, while
+> a scale of 50 will reduce it to half size.
+
 ## Usage
 
 Once configured and running, the application will overlay wind information on the camera's video stream. The overlay updates periodically (default every 120 seconds) with the latest data from FindWind.

findwind

@@ -258,19 +258,33 @@ download_svg() {
 	# Replace font-family with a known sans-serif font to improve chances of correct rendering (since the original font may not be available in the container)
 	# and set opacity on the first <g...> tag regardless of existing attributes.
 	opacity=$(get_non_empty_param Opacity)
-	echo "$svg" | \
-		sed -e "s#\(font-family='\)[^']*'#\1$FONT_FAMILY'#g" \
-			-e "s#\(font-family=\"\)[^\"]*\"#\1$FONT_FAMILY\"#g" \
-			-e "1,/<g[^>]*>/s#<g[^>]*>#<g opacity=\"$opacity\">#" | \
+	svg=$(echo "$svg" |sed -e "s#\(font-family='\)[^']*'#\1$FONT_FAMILY'#g" \
+		-e "s#\(font-family=\"\)[^\"]*\"#\1$FONT_FAMILY\"#g" \
+		-e "1,/<g[^>]*>/s#<g[^>]*>#<g opacity=\"$opacity\">#" | \
 		"$BASEDIR/usvg" \
 			--quiet \
 			--indent 0 \
 			--skip-system-fonts \
 			--use-fonts-dir "$FINDWIND_FONTS_DIR" \
-			- "$1" || {
+			- -c) || {
 		croak 'failed to render SVG text'
 		return 1
 	}
+
+	# Handle eventual scaling (with the consistent usvg output, strict format
+	# assumptions works and simplifies substitions).
+	scale=$(get_non_empty_param Scale)
+	[ "$scale" -eq 100 ] || {
+		dimensions=${svg%% xmlns*}
+		width=${dimensions##*width=\"}
+		width=${width%%\"*}
+		height=${dimensions##*height=\"}
+		height=${height%%\"*}
+		newwidth=$((width * scale / 100))
+		newheight=$((height * scale / 100))
+		svg=$(echo "$svg" |sed "s/<svg width=\"$width\" height=\"$height\" xmlns/<svg width=\"$newwidth\" height=\"$newheight\" viewBox=\"0 0 $width $height\" xmlns/")
+	}
+	echo "$svg" > "$1"
 }
 
 create_tmp_svg_file() {

manifest.json

@@ -8,7 +8,7 @@
             "vendorUrl": "https://github.com/d97jro",
             "vendorId": "1234567890",
             "runMode": "respawn",
-            "version": "1.1.1",
+            "version": "1.1.2",
             "compatibleOsVersions": [
                 {
                     "max": "13"
@@ -37,6 +37,11 @@
                     "type": "enum:topLeft|Top left, topRight|Top right, bottomLeft|Bottom left, bottomRight|Bottom right, custom|Custom position",
                     "default": "topLeft"
                 },
+                {
+                    "name": "Scale",
+                    "type": "int:min=10,max=900",
+                    "default": "100"
+                },
                 {
                     "name": "CustomPositionX",
                     "type": "double:min=-1,max=1",