Added smoothstep built-in function

(cherry picked from commit dd9357d41c)

doc_classes/VisualScriptBuiltinFunc.xml

@@ -202,7 +202,14 @@
 		<constant name="COLORN" value="62" enum="BuiltinFunc">
 			Return the [Color] with the given name and alpha ranging from 0 to 1. Note: names are defined in color_names.inc.
 		</constant>
-		<constant name="FUNC_MAX" value="63" enum="BuiltinFunc">
+		<constant name="MATH_SMOOTHSTEP" value="63" enum="BuiltinFunc">
+			Return a number smoothly interpolated between the first two inputs, based on the third input. Similar to [code]MATH_LERP[/code], but interpolates faster at the beginning and slower at the end. Using Hermite interpolation formula:
+			[codeblock]
+			var t = clamp((weight - from) / (to - from), 0.0, 1.0)
+			return t * t * (3.0 - 2.0 * t)
+			[/codeblock]
+		</constant>
+		<constant name="FUNC_MAX" value="64" enum="BuiltinFunc">
 			The maximum value the [member function] property can have.
 		</constant>
 	</constants>

visual_script_builtin_funcs.cpp

@@ -102,6 +102,7 @@ const char *VisualScriptBuiltinFunc::func_name[VisualScriptBuiltinFunc::FUNC_MAX
 	"var2bytes",
 	"bytes2var",
 	"color_named",
+	"smoothstep",
 };
 
 VisualScriptBuiltinFunc::BuiltinFunc VisualScriptBuiltinFunc::find_function(const String &p_string) {
@@ -204,6 +205,7 @@ int VisualScriptBuiltinFunc::get_func_argument_count(BuiltinFunc p_func) {
 			return 2;
 		case MATH_LERP:
 		case MATH_INVERSE_LERP:
+		case MATH_SMOOTHSTEP:
 		case MATH_DECTIME:
 		case MATH_WRAP:
 		case MATH_WRAPF:
@@ -337,6 +339,14 @@ PropertyInfo VisualScriptBuiltinFunc::get_input_value_port_info(int p_idx) const
 			else
 				return PropertyInfo(Variant::REAL, "ostop");
 		} break;
+		case MATH_SMOOTHSTEP: {
+			if (p_idx == 0)
+				return PropertyInfo(Variant::REAL, "from");
+			else if (p_idx == 1)
+				return PropertyInfo(Variant::REAL, "to");
+			else
+				return PropertyInfo(Variant::REAL, "weight");
+		} break;
 		case MATH_DECTIME: {
 			if (p_idx == 0)
 				return PropertyInfo(Variant::REAL, "value");
@@ -569,6 +579,7 @@ PropertyInfo VisualScriptBuiltinFunc::get_output_value_port_info(int p_idx) cons
 		case MATH_LERP:
 		case MATH_INVERSE_LERP:
 		case MATH_RANGE_LERP:
+		case MATH_SMOOTHSTEP:
 		case MATH_DECTIME: {
 			t = Variant::REAL;
 
@@ -899,6 +910,12 @@ void VisualScriptBuiltinFunc::exec_func(BuiltinFunc p_func, const Variant **p_in
 			VALIDATE_ARG_NUM(4);
 			*r_return = Math::range_lerp((double)*p_inputs[0], (double)*p_inputs[1], (double)*p_inputs[2], (double)*p_inputs[3], (double)*p_inputs[4]);
 		} break;
+		case VisualScriptBuiltinFunc::MATH_SMOOTHSTEP: {
+			VALIDATE_ARG_NUM(0);
+			VALIDATE_ARG_NUM(1);
+			VALIDATE_ARG_NUM(2);
+			*r_return = Math::smoothstep((double)*p_inputs[0], (double)*p_inputs[1], (double)*p_inputs[2]);
+		} break;
 		case VisualScriptBuiltinFunc::MATH_DECTIME: {
 
 			VALIDATE_ARG_NUM(0);
@@ -1379,6 +1396,7 @@ void VisualScriptBuiltinFunc::_bind_methods() {
 	BIND_ENUM_CONSTANT(VAR_TO_BYTES);
 	BIND_ENUM_CONSTANT(BYTES_TO_VAR);
 	BIND_ENUM_CONSTANT(COLORN);
+	BIND_ENUM_CONSTANT(MATH_SMOOTHSTEP);
 	BIND_ENUM_CONSTANT(FUNC_MAX);
 }
 
@@ -1433,6 +1451,7 @@ void register_visual_script_builtin_func_node() {
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/lerp", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_LERP>);
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/inverse_lerp", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_INVERSE_LERP>);
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/range_lerp", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_RANGE_LERP>);
+	VisualScriptLanguage::singleton->add_register_func("functions/built_in/smoothstep", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_SMOOTHSTEP>);
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/dectime", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_DECTIME>);
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/randomize", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_RANDOMIZE>);
 	VisualScriptLanguage::singleton->add_register_func("functions/built_in/rand", create_builtin_func_node<VisualScriptBuiltinFunc::MATH_RAND>);

visual_script_builtin_funcs.h

@@ -101,6 +101,7 @@ public:
 		VAR_TO_BYTES,
 		BYTES_TO_VAR,
 		COLORN,
+		MATH_SMOOTHSTEP,
 		FUNC_MAX
 	};