Saturation node added

addons/ShaderLib/Artistic/Adjustment/Saturation.gd

@@ -0,0 +1,61 @@
+@tool
+class_name VisualShaderNodeAdjustmentSaturation extends VisualShaderNodeCustom
+
+
+func _get_name() -> String:
+	return "Saturation"
+
+func _get_category() -> String:
+	return "Artistic/Adjustment"
+
+func _get_description() -> String:
+	return "Adjusts the saturation of input \"in\" by the amount of input \"saturation\"."
+
+func _get_return_icon_type() -> PortType:
+	return PORT_TYPE_VECTOR_3D
+
+func _get_input_port_count() -> int:
+	return 2
+
+func _get_input_port_name(port: int) -> String:
+	match port:
+		0:
+			return "in"
+		_:
+			return "saturation"
+
+func _get_input_port_type(port: int) -> PortType:
+	match port:
+		0:
+			return PORT_TYPE_VECTOR_3D
+		_:
+			return PORT_TYPE_SCALAR
+
+func _get_input_port_default_value(port: int) -> Variant:
+	match port:
+		0:
+			return null
+		_:
+			return 1.0
+
+func _get_output_port_count() -> int:
+	return 1
+
+func _get_output_port_name(port: int) -> String:
+	return "out"
+
+func _get_output_port_type(port: int) -> PortType:
+	return PORT_TYPE_VECTOR_3D
+
+func _get_global_code(mode: Shader.Mode) -> String:
+	var code: String = preload("Saturation.gdshaderinc").code
+	return code
+
+func _get_code(input_vars: Array[String], output_vars: Array[String], mode: Shader.Mode, type: VisualShader.Type) -> String:
+	var input: String = "vec3(1.0)"
+
+	if input_vars[0]:
+		input = input_vars[0]
+
+	var saturation = input_vars[1]
+	return output_vars[0] + " = saturation(%s, %s);" % [input, saturation]

addons/ShaderLib/Artistic/Adjustment/Saturation.gdshaderinc

@@ -0,0 +1,4 @@
+vec3 saturation(vec3 input, float saturation){
+    float luma = dot(input, vec3(0.2126729, 0.7151522, 0.0721750));
+    return luma + saturation * (input - vec3(luma));
+}