Darken and lighten functions for schemes

lib/apply_scheme_to_template.sh

@@ -20,6 +20,41 @@ rgb_b() {
 	printf "$((0x${MO_FUNCTION_ARGS[0]:4:4}))"
 }
 
+rgb() {
+	rgb_r; printf " "
+	rgb_g; printf " "
+	rgb_b; printf " "
+}
+
+clamp() {
+	if [[ $1 -lt 0 ]]; then
+		printf "0"
+	else
+		if [[ $1 -gt 255 ]]; then
+			printf "255"
+		else
+			printf "%s" "$1"
+		fi
+	fi
+}
+
+lighten() {
+	mod="${MO_FUNCTION_ARGS[1]}"
+	parts=("$(rgb_r)" "$(rgb_g)" "$(rgb_b)")
+	vars=""
+	for part in "${parts[@]}"; do
+		let var=$part+$mod
+		vars=$vars"$(clamp "$var") "
+	done
+
+	printf "%02x%02x%02x" $vars
+}
+
+darken() {
+	MO_FUNCTION_ARGS[1]="-${MO_FUNCTION_ARGS[1]}"
+	lighten
+}
+
 set -a # All variables after this will be exported
 source $SCHEME
 mo "$TEMPLATE"