ScriptableRenderPipeline/MaterialGraphProject/Assets/UnityShaderEditor/Runtime/Nodes/AddNode.cs

namespace UnityEngine.MaterialGraph
{
    [Title("Math/Add Node")]
    public class AddNode : Function2Input, IGeneratesFunction
    {
        public AddNode()
        {
            name = "AddNode";
        }

        protected override string GetFunctionName()
        {
            return "unity_add_" + precision;
        }

        public void GenerateNodeFunction(ShaderGenerator visitor, GenerationMode generationMode)
        {
            var outputString = new ShaderGenerator();
            outputString.AddShaderChunk(GetFunctionPrototype("arg1", "arg2"), false);
            outputString.AddShaderChunk("{", false);
            outputString.Indent();
            outputString.AddShaderChunk("return arg1 + arg2;", false);
            outputString.Deindent();
            outputString.AddShaderChunk("}", false);

            visitor.AddShaderChunk(outputString.GetShaderString(0), true);
        }
    }
}