Auto-set a first compatible uniform on dragging to create a UniformRef

editor/plugins/visual_shader_editor_plugin.cpp

@@ -2274,6 +2274,8 @@ void VisualShaderEditor::_setup_node(VisualShaderNode *p_node, int p_op_idx) {
 void VisualShaderEditor::_add_node(int p_idx, int p_op_idx, String p_resource_path, int p_node_idx) {
 	ERR_FAIL_INDEX(p_idx, add_options.size());
 
+	VisualShader::Type type = get_current_shader_type();
+
 	Ref<VisualShaderNode> vsnode;
 
 	bool is_custom = add_options[p_idx].is_custom;
@@ -2300,6 +2302,29 @@ void VisualShaderEditor::_add_node(int p_idx, int p_op_idx, String p_resource_pa
 			}
 		}
 
+		VisualShaderNodeUniformRef *uniform_ref = Object::cast_to<VisualShaderNodeUniformRef>(vsn);
+
+		if (uniform_ref && to_node != -1 && to_slot != -1) {
+			VisualShaderNode::PortType input_port_type = visual_shader->get_node(type, to_node)->get_input_port_type(to_slot);
+			bool success = false;
+
+			for (int i = 0; i < uniform_ref->get_uniforms_count(); i++) {
+				if (uniform_ref->get_port_type_by_index(i) == input_port_type) {
+					uniform_ref->set_uniform_name(uniform_ref->get_uniform_name_by_index(i));
+					success = true;
+					break;
+				}
+			}
+			if (!success) {
+				for (int i = 0; i < uniform_ref->get_uniforms_count(); i++) {
+					if (visual_shader->is_port_types_compatible(uniform_ref->get_port_type_by_index(i), input_port_type)) {
+						uniform_ref->set_uniform_name(uniform_ref->get_uniform_name_by_index(i));
+						break;
+					}
+				}
+			}
+		}
+
 		vsnode = Ref<VisualShaderNode>(vsn);
 	} else {
 		ERR_FAIL_COND(add_options[p_idx].script.is_null());
@@ -2320,8 +2345,6 @@ void VisualShaderEditor::_add_node(int p_idx, int p_op_idx, String p_resource_pa
 	}
 	saved_node_pos_dirty = false;
 
-	VisualShader::Type type = get_current_shader_type();
-
 	int id_to_use = visual_shader->get_valid_node_id(type);
 
 	if (p_resource_path.is_empty()) {

scene/resources/visual_shader.cpp

@@ -2708,6 +2708,28 @@ VisualShaderNodeUniformRef::UniformType VisualShaderNodeUniformRef::get_uniform_
 	return UniformType::UNIFORM_TYPE_FLOAT;
 }
 
+VisualShaderNodeUniformRef::PortType VisualShaderNodeUniformRef::get_port_type_by_index(int p_idx) const {
+	if (p_idx >= 0 && p_idx < uniforms.size()) {
+		switch (uniforms[p_idx].type) {
+			case UniformType::UNIFORM_TYPE_FLOAT:
+				return PORT_TYPE_SCALAR;
+			case UniformType::UNIFORM_TYPE_INT:
+				return PORT_TYPE_SCALAR_INT;
+			case UniformType::UNIFORM_TYPE_SAMPLER:
+				return PORT_TYPE_SAMPLER;
+			case UniformType::UNIFORM_TYPE_VECTOR:
+				return PORT_TYPE_VECTOR;
+			case UniformType::UNIFORM_TYPE_TRANSFORM:
+				return PORT_TYPE_TRANSFORM;
+			case UniformType::UNIFORM_TYPE_COLOR:
+				return PORT_TYPE_VECTOR;
+			default:
+				break;
+		}
+	}
+	return PORT_TYPE_SCALAR;
+}
+
 String VisualShaderNodeUniformRef::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 {
 	switch (uniform_type) {
 		case UniformType::UNIFORM_TYPE_FLOAT:

scene/resources/visual_shader.h

@@ -517,6 +517,7 @@ public:
 	String get_uniform_name_by_index(int p_idx) const;
 	UniformType get_uniform_type_by_name(const String &p_name) const;
 	UniformType get_uniform_type_by_index(int p_idx) const;
+	PortType get_port_type_by_index(int p_idx) const;
 
 	virtual Vector<StringName> get_editable_properties() const override;