Merge pull request #36225 from Chaosus/shader_fma

Added 'fma' function to shader language

8 files changed, 199 insertions, 0 deletions

diff --git a/doc/classes/VisualShaderNodeMultiplyAdd.xml b/doc/classes/VisualShaderNodeMultiplyAdd.xml
new file mode 100644
index 0000000000..ba79b3fe8f
--- /dev/null
+++ b/doc/classes/VisualShaderNodeMultiplyAdd.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<class name="VisualShaderNodeMultiplyAdd" inherits="VisualShaderNode" version="4.0">
+	<brief_description>
+		Performs a fused multiply-add operation within the visual shader graph.
+	</brief_description>
+	<description>
+		Uses three operands to compute [code](a * b + c)[/code] expression.
+	</description>
+	<tutorials>
+	</tutorials>
+	<methods>
+	</methods>
+	<members>
+		<member name="type" type="int" setter="set_type" getter="get_type" enum="VisualShaderNodeMultiplyAdd.Type" default="0">
+			A type of operands and returned value.
+		</member>
+	</members>
+	<constants>
+		<constant name="TYPE_SCALAR" value="0" enum="Type">
+			A scalar type.
+		</constant>
+		<constant name="TYPE_VECTOR" value="1" enum="Type">
+			A vector type.
+		</constant>
+		<constant name="TYPE_MAX" value="2" enum="Type">
+			Represents the size of the [enum Type] enum.
+		</constant>
+	</constants>
+</class>
diff --git a/drivers/gles2/shader_compiler_gles2.cpp b/drivers/gles2/shader_compiler_gles2.cpp
index a5e85424b7..1e30f0dfa1 100644
--- a/drivers/gles2/shader_compiler_gles2.cpp
+++ b/drivers/gles2/shader_compiler_gles2.cpp
@@ -1016,6 +1016,7 @@ ShaderCompilerGLES2::ShaderCompilerGLES2() {
 	actions[RS::SHADER_CANVAS_ITEM].usage_defines["isinf"] = "#define IS_INF_USED\n";
 	actions[RS::SHADER_CANVAS_ITEM].usage_defines["isnan"] = "#define IS_NAN_USED\n";
 	actions[RS::SHADER_CANVAS_ITEM].usage_defines["trunc"] = "#define TRUNC_USED\n";
+	actions[RS::SHADER_CANVAS_ITEM].usage_defines["fma"] = "#define FMA_USED\n";
 
 	/** SPATIAL SHADER **/
 
@@ -1126,6 +1127,7 @@ ShaderCompilerGLES2::ShaderCompilerGLES2() {
 	actions[RS::SHADER_SPATIAL].usage_defines["isinf"] = "#define IS_INF_USED\n";
 	actions[RS::SHADER_SPATIAL].usage_defines["isnan"] = "#define IS_NAN_USED\n";
 	actions[RS::SHADER_SPATIAL].usage_defines["trunc"] = "#define TRUNC_USED\n";
+	actions[RS::SHADER_SPATIAL].usage_defines["fma"] = "#define FMA_USED\n";
 
 	actions[RS::SHADER_SPATIAL].render_mode_defines["skip_vertex_transform"] = "#define SKIP_TRANSFORM_USED\n";
 	actions[RS::SHADER_SPATIAL].render_mode_defines["world_vertex_coords"] = "#define VERTEX_WORLD_COORDS_USED\n";
diff --git a/drivers/gles2/shaders/stdlib.glsl b/drivers/gles2/shaders/stdlib.glsl
index 9c74418743..807036dda6 100644
--- a/drivers/gles2/shaders/stdlib.glsl
+++ b/drivers/gles2/shaders/stdlib.glsl
@@ -417,4 +417,24 @@ highp mat4 outerProduct(highp vec4 c, highp vec4 r) {
 
 #endif
 
+#if defined(FMA_USED)
+
+highp float fma(highp float a, highp float b, highp float c) {
+	return a * b + c;
+}
+
+highp vec2 fma(highp vec2 a, highp vec2 b, highp vec2 c) {
+	return a * b + c;
+}
+
+highp vec3 fma(highp vec3 a, highp vec3 b, highp vec3 c) {
+	return a * b + c;
+}
+
+highp vec4 fma(highp vec4 a, highp vec4 b, highp vec4 c) {
+	return a * b + c;
+}
+
+#endif
+
 #endif
diff --git a/editor/plugins/visual_shader_editor_plugin.cpp b/editor/plugins/visual_shader_editor_plugin.cpp
index 13d8f0c856..c19140ae7c 100644
--- a/editor/plugins/visual_shader_editor_plugin.cpp
+++ b/editor/plugins/visual_shader_editor_plugin.cpp
@@ -1392,6 +1392,12 @@ VisualShaderNode *VisualShaderEditor::_add_node(int p_idx, int p_op_idx) {
 			if (vderFunc) {
 				vderFunc->set_function((VisualShaderNodeVectorDerivativeFunc::Function)p_op_idx);
 			}
+
+			VisualShaderNodeMultiplyAdd *fmaFunc = Object::cast_to<VisualShaderNodeMultiplyAdd>(vsn);
+
+			if (fmaFunc) {
+				fmaFunc->set_type((VisualShaderNodeMultiplyAdd::Type)p_op_idx);
+			}
 		}
 
 		vsnode = Ref<VisualShaderNode>(vsn);
@@ -2711,6 +2717,7 @@ VisualShaderEditor::VisualShaderEditor() {
 	add_options.push_back(AddOption("Max", "Scalar", "Functions", "VisualShaderNodeFloatOp", TTR("Returns the greater of two values."), VisualShaderNodeFloatOp::OP_MAX, VisualShaderNode::PORT_TYPE_SCALAR));
 	add_options.push_back(AddOption("Min", "Scalar", "Functions", "VisualShaderNodeFloatOp", TTR("Returns the lesser of two values."), VisualShaderNodeFloatOp::OP_MIN, VisualShaderNode::PORT_TYPE_SCALAR));
 	add_options.push_back(AddOption("Mix", "Scalar", "Functions", "VisualShaderNodeScalarInterp", TTR("Linear interpolation between two scalars."), -1, VisualShaderNode::PORT_TYPE_SCALAR));
+	add_options.push_back(AddOption("MultiplyAdd", "Scalar", "Functions", "VisualShaderNodeMultiplyAdd", TTR("Performs a fused multiply-add operation (a * b + c) on scalars."), VisualShaderNodeMultiplyAdd::TYPE_SCALAR, VisualShaderNode::PORT_TYPE_SCALAR));
 	add_options.push_back(AddOption("Negate", "Scalar", "Functions", "VisualShaderNodeFloatFunc", TTR("Returns the opposite value of the parameter."), VisualShaderNodeFloatFunc::FUNC_NEGATE, VisualShaderNode::PORT_TYPE_SCALAR));
 	add_options.push_back(AddOption("Negate", "Scalar", "Functions", "VisualShaderNodeIntFunc", TTR("Returns the opposite value of the parameter."), VisualShaderNodeIntFunc::FUNC_NEGATE, VisualShaderNode::PORT_TYPE_SCALAR_INT));
 	add_options.push_back(AddOption("OneMinus", "Scalar", "Functions", "VisualShaderNodeFloatFunc", TTR("1.0 - scalar"), VisualShaderNodeFloatFunc::FUNC_ONEMINUS, VisualShaderNode::PORT_TYPE_SCALAR));
@@ -2813,6 +2820,7 @@ VisualShaderEditor::VisualShaderEditor() {
 	add_options.push_back(AddOption("Min", "Vector", "Functions", "VisualShaderNodeVectorOp", TTR("Returns the lesser of two values."), VisualShaderNodeVectorOp::OP_MIN, VisualShaderNode::PORT_TYPE_VECTOR));
 	add_options.push_back(AddOption("Mix", "Vector", "Functions", "VisualShaderNodeVectorInterp", TTR("Linear interpolation between two vectors."), -1, VisualShaderNode::PORT_TYPE_VECTOR));
 	add_options.push_back(AddOption("MixS", "Vector", "Functions", "VisualShaderNodeVectorScalarMix", TTR("Linear interpolation between two vectors using scalar."), -1, VisualShaderNode::PORT_TYPE_VECTOR));
+	add_options.push_back(AddOption("MultiplyAdd", "Vector", "Functions", "VisualShaderNodeMultiplyAdd", TTR("Performs a fused multiply-add operation (a * b + c) on vectors."), VisualShaderNodeMultiplyAdd::TYPE_VECTOR, VisualShaderNode::PORT_TYPE_VECTOR));
 	add_options.push_back(AddOption("Negate", "Vector", "Functions", "VisualShaderNodeVectorFunc", TTR("Returns the opposite value of the parameter."), VisualShaderNodeVectorFunc::FUNC_NEGATE, VisualShaderNode::PORT_TYPE_VECTOR));
 	add_options.push_back(AddOption("Normalize", "Vector", "Functions", "VisualShaderNodeVectorFunc", TTR("Calculates the normalize product of vector."), VisualShaderNodeVectorFunc::FUNC_NORMALIZE, VisualShaderNode::PORT_TYPE_VECTOR));
 	add_options.push_back(AddOption("OneMinus", "Vector", "Functions", "VisualShaderNodeVectorFunc", TTR("1.0 - vector"), VisualShaderNodeVectorFunc::FUNC_ONEMINUS, VisualShaderNode::PORT_TYPE_VECTOR));
diff --git a/scene/register_scene_types.cpp b/scene/register_scene_types.cpp
index 86ea0406e1..f40fb78056 100644
--- a/scene/register_scene_types.cpp
+++ b/scene/register_scene_types.cpp
@@ -562,6 +562,7 @@ void register_scene_types() {
 	ClassDB::register_class<VisualShaderNodeGlobalExpression>();
 	ClassDB::register_class<VisualShaderNodeIs>();
 	ClassDB::register_class<VisualShaderNodeCompare>();
+	ClassDB::register_class<VisualShaderNodeMultiplyAdd>();
 
 	ClassDB::register_class<ShaderMaterial>();
 	ClassDB::register_virtual_class<CanvasItem>();
diff --git a/scene/resources/visual_shader_nodes.cpp b/scene/resources/visual_shader_nodes.cpp
index 5c6b13a527..88f5287831 100644
--- a/scene/resources/visual_shader_nodes.cpp
+++ b/scene/resources/visual_shader_nodes.cpp
@@ -4794,3 +4794,96 @@ VisualShaderNodeCompare::VisualShaderNodeCompare() {
 	set_input_port_default_value(1, 0.0);
 	set_input_port_default_value(2, CMP_EPSILON);
 }
+
+////////////// Fma
+
+String VisualShaderNodeMultiplyAdd::get_caption() const {
+	return "MultiplyAdd";
+}
+
+int VisualShaderNodeMultiplyAdd::get_input_port_count() const {
+	return 3;
+}
+
+VisualShaderNodeMultiplyAdd::PortType VisualShaderNodeMultiplyAdd::get_input_port_type(int p_port) const {
+	if (type == TYPE_SCALAR) {
+		return PORT_TYPE_SCALAR;
+	}
+	return PORT_TYPE_VECTOR;
+}
+
+String VisualShaderNodeMultiplyAdd::get_input_port_name(int p_port) const {
+	if (p_port == 0) {
+		return "a";
+	} else if (p_port == 1) {
+		return "b(*)";
+	} else if (p_port == 2) {
+		return "c(+)";
+	}
+	return "";
+}
+
+int VisualShaderNodeMultiplyAdd::get_output_port_count() const {
+	return 1;
+}
+
+VisualShaderNodeMultiplyAdd::PortType VisualShaderNodeMultiplyAdd::get_output_port_type(int p_port) const {
+	if (type == TYPE_SCALAR) {
+		return PORT_TYPE_SCALAR;
+	} else {
+		return PORT_TYPE_VECTOR;
+	}
+}
+
+String VisualShaderNodeMultiplyAdd::get_output_port_name(int p_port) const {
+	return "";
+}
+
+String VisualShaderNodeMultiplyAdd::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
+	return "\t" + p_output_vars[0] + " = fma(" + p_input_vars[0] + ", " + p_input_vars[1] + ", " + p_input_vars[2] + ");\n";
+}
+
+void VisualShaderNodeMultiplyAdd::set_type(Type p_type) {
+	ERR_FAIL_INDEX((int)p_type, TYPE_MAX);
+	if (p_type != type) {
+		if (p_type == TYPE_SCALAR) {
+			set_input_port_default_value(0, 0.0);
+			set_input_port_default_value(1, 0.0);
+			set_input_port_default_value(2, 0.0);
+		} else {
+			set_input_port_default_value(0, Vector3(0.0, 0.0, 0.0));
+			set_input_port_default_value(1, Vector3(0.0, 0.0, 0.0));
+			set_input_port_default_value(2, Vector3(0.0, 0.0, 0.0));
+		}
+	}
+	type = p_type;
+	emit_changed();
+}
+
+VisualShaderNodeMultiplyAdd::Type VisualShaderNodeMultiplyAdd::get_type() const {
+	return type;
+}
+
+Vector<StringName> VisualShaderNodeMultiplyAdd::get_editable_properties() const {
+	Vector<StringName> props;
+	props.push_back("type");
+	return props;
+}
+
+void VisualShaderNodeMultiplyAdd::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("set_type", "type"), &VisualShaderNodeMultiplyAdd::set_type);
+	ClassDB::bind_method(D_METHOD("get_type"), &VisualShaderNodeMultiplyAdd::get_type);
+
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "type", PROPERTY_HINT_ENUM, "Scalar,Vector"), "set_type", "get_type");
+
+	BIND_ENUM_CONSTANT(TYPE_SCALAR);
+	BIND_ENUM_CONSTANT(TYPE_VECTOR);
+	BIND_ENUM_CONSTANT(TYPE_MAX);
+}
+
+VisualShaderNodeMultiplyAdd::VisualShaderNodeMultiplyAdd() {
+	type = TYPE_SCALAR;
+	set_input_port_default_value(0, 0.0);
+	set_input_port_default_value(1, 0.0);
+	set_input_port_default_value(2, 0.0);
+}
diff --git a/scene/resources/visual_shader_nodes.h b/scene/resources/visual_shader_nodes.h
index 28a9de6819..de91822b1e 100644
--- a/scene/resources/visual_shader_nodes.h
+++ b/scene/resources/visual_shader_nodes.h
@@ -1995,4 +1995,43 @@ VARIANT_ENUM_CAST(VisualShaderNodeCompare::ComparisonType)
 VARIANT_ENUM_CAST(VisualShaderNodeCompare::Function)
 VARIANT_ENUM_CAST(VisualShaderNodeCompare::Condition)
 
+class VisualShaderNodeMultiplyAdd : public VisualShaderNode {
+	GDCLASS(VisualShaderNodeMultiplyAdd, VisualShaderNode);
+
+public:
+	enum Type {
+		TYPE_SCALAR,
+		TYPE_VECTOR,
+		TYPE_MAX,
+	};
+
+protected:
+	Type type;
+
+protected:
+	static void _bind_methods();
+
+public:
+	virtual String get_caption() const;
+
+	virtual int get_input_port_count() const;
+	virtual PortType get_input_port_type(int p_port) const;
+	virtual String get_input_port_name(int p_port) const;
+
+	virtual int get_output_port_count() const;
+	virtual PortType get_output_port_type(int p_port) const;
+	virtual String get_output_port_name(int p_port) const;
+
+	virtual String generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview = false) const; //if no output is connected, the output var passed will be empty. if no input is connected and input is NIL, the input var passed will be empty
+
+	void set_type(Type p_type);
+	Type get_type() const;
+
+	virtual Vector<StringName> get_editable_properties() const;
+
+	VisualShaderNodeMultiplyAdd();
+};
+
+VARIANT_ENUM_CAST(VisualShaderNodeMultiplyAdd::Type)
+
 #endif // VISUAL_SHADER_NODES_H
diff --git a/servers/rendering/shader_language.cpp b/servers/rendering/shader_language.cpp
index 99cc76b2e3..1f30048a51 100644
--- a/servers/rendering/shader_language.cpp
+++ b/servers/rendering/shader_language.cpp
@@ -2135,6 +2135,13 @@ const ShaderLanguage::BuiltinFuncDef ShaderLanguage::builtin_func_defs[] = {
 	//array
 	{ "length", TYPE_INT, { TYPE_VOID }, TAG_ARRAY, true },
 
+	// modern functions
+
+	{ "fma", TYPE_FLOAT, { TYPE_FLOAT, TYPE_FLOAT, TYPE_FLOAT, TYPE_VOID }, TAG_GLOBAL, true },
+	{ "fma", TYPE_VEC2, { TYPE_VEC2, TYPE_VEC2, TYPE_VEC2, TYPE_VOID }, TAG_GLOBAL, true },
+	{ "fma", TYPE_VEC3, { TYPE_VEC3, TYPE_VEC3, TYPE_VEC3, TYPE_VOID }, TAG_GLOBAL, true },
+	{ "fma", TYPE_VEC4, { TYPE_VEC4, TYPE_VEC4, TYPE_VEC4, TYPE_VOID }, TAG_GLOBAL, true },
+
 	{ nullptr, TYPE_VOID, { TYPE_VOID }, TAG_GLOBAL, false }
 
 };