White balance node added

addons/ShaderLib/Artistic/Adjustment/WhiteBalance.gd

@@ -0,0 +1,64 @@
+@tool
+class_name VisualShaderNodeWhiteBalance extends VisualShaderNodeCustom
+
+func _get_name() -> String:
+	return "WhiteBalance"
+
+func _get_category() -> String:
+	return "Artistic/Adjustment"
+
+func _get_description() -> String:
+	return "Adjusts the temperature and tint of input \"in\" by the amount of inputs \"temperature\" and \"tint\" respectively."
+
+func _get_return_icon_type() -> PortType:
+	return PORT_TYPE_VECTOR_3D
+
+func _get_input_port_count() -> int:
+	return 3
+
+func _get_input_port_name(port: int) -> String:
+	match port:
+		0:
+			return "in"
+		1:
+			return "temperature"
+		_:
+			return "tint"
+
+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:
+		1, 2:
+			return 0.0
+		_:
+			return null
+
+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("WhiteBalance.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 temperature: String = input_vars[1]
+	var tint: String = input_vars[2]
+
+	return output_vars[0] + " = white_balance(%s, %s, %s);" % [input, temperature, tint]

addons/ShaderLib/Artistic/Adjustment/WhiteBalance.gdshaderinc

@@ -0,0 +1,36 @@
+vec3 white_balance(vec3 input, float temperature, float tint){
+	float t1 = temperature * 10.0 / 6.0;
+	float t2 = tint * 10.0 / 6.0;
+
+	float x = 0.31271 - t1 * (t1 < 0.0 ? 0.1 : 0.05);
+	float standard_illuminant_y = 2.87 * x - 3.0 * x * x - 0.27509507;
+	float y = standard_illuminant_y + t2 * 0.05;
+
+	vec3 w1 = vec3(0.949237, 1.03542, 1.08728);
+
+	float Y = 1.;
+	float X = Y * x / y;
+	float Z = Y * (1. - x - y) / y;
+	float L = 0.7328 * X + 0.4296 * Y - 0.1624 * Z;
+	float M = -0.7036 * X + 1.6975 * Y + 0.0061 * Z;
+	float S = 0.0030 * X + 0.0136 * Y + 0.9834 * Z;
+	vec3 w2 = vec3(L, M, S);
+
+	vec3 balance = vec3(w1.x / w2.x, w1.y / w2.y, w1.z / w2.z);
+
+	mat3 LIN_2_LMS_MAT = mat3(
+		vec3(3.90405e-1, 5.49941e-1, 8.92632e-3),
+		vec3(7.08416e-2, 9.63172e-1, 1.35775e-3),
+		vec3(2.31082e-2, 1.28021e-1, 9.36245e-1)
+	);
+
+	mat3 LMS_2_LIN_MAT = mat3(
+		vec3(2.85847, -1.62879, -2.48910),
+		vec3(-2.10182e-1,  1.15820e+0,  3.24281e-4),
+		vec3(-4.18120e-2, -1.18169e-1,  1.06867e+0)
+		);
+
+	vec3 lms = LIN_2_LMS_MAT * input;
+	lms *= balance;
+	return LMS_2_LIN_MAT * lms;
+}