How to get shader source code from script?

Unity Engine
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1

The main issue I trying to solve is that shader graphs are not working with unity’s UI Mask (not maskable). This can be easily fixed by adding a few lines of code into generated shader code. What I try to do, is to automate the process: select shader graph asset in project → choose menu button → source code extracted from shader, lines added, new *.shader file created with modified code.
So, that’s the problem: how to get compiled code from script?

I found out how to get particular Pass code (HLSL Program), but what about ShaderLab part?

What I can do, is to grab generated code from Temp folder, or copy it from buffer. But for this, I need to press “View Generated Shader” or “Copy Shader”…

1 Like
2

+1

I would be happy to have this functionality at hand.

1 Like
3

Personally I ended up with the next flow: choose shaderGraph file, press “Copy Shader” button, then go to my custom menu and launch my custom function - which will grab shader’s code from clipboard, parse and modify it, and then creates a new shader file, and imports in via assets database. I’ll ask the permission to share the code from my customer, let’s see, what he’ll answers.

4

Hi, could anybody automate this?

5

Until there is an official API you can use this (2021.3.18f1):

private static string GenerateShaderCode(string shaderAssetPath, string shaderName = null)
{
    Type editorType =
        Type.GetType("UnityEditor.ShaderGraph.ShaderGraphImporterEditor, Unity.ShaderGraph.Editor")!;
    Type generatorType =
        Type.GetType("UnityEditor.ShaderGraph.Generator, Unity.ShaderGraph.Editor")!;
    Type modeType =
        Type.GetType("UnityEditor.ShaderGraph.GenerationMode, Unity.ShaderGraph.Editor")!;

    MethodInfo method = editorType.GetMethod(
        "<OnInspectorGUI>g__GetGraphData|2_0",
        BindingFlags.NonPublic | BindingFlags.Static
    )!;
    shaderName ??= Path.GetFileNameWithoutExtension(shaderAssetPath);
    var importer = AssetImporter.GetAtPath(shaderAssetPath);
    object graphData = method.Invoke(null, new object[] { importer });

    // new Generator(graphData, null, GenerationMode.ForReals, assetName, null, true);
    object forReals = ((FieldInfo)modeType.GetMember("ForReals")[0]).GetValue(null);
    object generator = Activator.CreateInstance(
        generatorType, graphData, null,
        forReals, shaderName, null, true
    );
    object shaderCode = generatorType
        .GetProperty("generatedShader", BindingFlags.Public | BindingFlags.Instance)!
        .GetValue(generator);

    return (string)shaderCode;
}

It’s hideous, but it works :smile:

4 Likes
6

Some how I can’t call the method by “g__GetGraphData|2_0”
So I implement a more complex one and support ShaderGraph 14.0

    private static object GetGraphData(string shaderAssetPath)
    {
        var importer = AssetImporter.GetAtPath(shaderAssetPath);

        var textGraph = File.ReadAllText(importer.assetPath, Encoding.UTF8);
        var graphObjectType = Type.GetType("UnityEditor.Graphing.GraphObject, Unity.ShaderGraph.Editor")!;

        // var graphObject = CreateInstance<GraphObject>();
        var graphObject = ScriptableObject.CreateInstance(graphObjectType);

        graphObject.hideFlags = HideFlags.HideAndDontSave;
        bool isSubGraph;
        var extension = Path.GetExtension(importer.assetPath).Replace(".", "");
        switch (extension)
        {
            case "shadergraph":
                isSubGraph = false;
                break;
            case "ShaderGraph":
                isSubGraph = false;
                break;
            case "shadersubgraph":
                isSubGraph = true;
                break;
            default:
                throw new Exception($"Invalid file extension {extension}");
        }
        var assetGuid = AssetDatabase.AssetPathToGUID(importer.assetPath);
       
        // graphObject.graph = new GraphData { assetGuid = assetGuid, isSubGraph = isSubGraph, messageManager = null };
        var graphObject_graphProperty = graphObjectType.GetProperty("graph")!;
        var graphDataType = Type.GetType("UnityEditor.ShaderGraph.GraphData, Unity.ShaderGraph.Editor")!;
        var graphDataInstance = Activator.CreateInstance(graphDataType);
        graphDataType.GetProperty("assetGuid")!.SetValue(graphDataInstance, assetGuid);
        graphDataType.GetProperty("isSubGraph")!.SetValue(graphDataInstance, isSubGraph);
        graphDataType.GetProperty("messageManager")!.SetValue(graphDataInstance, null);
        graphObject_graphProperty.SetValue(graphObject, graphDataInstance);

        // MultiJson.Deserialize(graphObject.graph, textGraph);
        // = MultiJson.Deserialize<JsonObject>(graphObject.graph, textGraph, null, false);
        var multiJsonType = Type.GetType("UnityEditor.ShaderGraph.Serialization.MultiJson, Unity.ShaderGraph.Editor")!;
        var deserializeMethod = multiJsonType.GetMethod("Deserialize")!;
        var descrializeGenericMethod = deserializeMethod.MakeGenericMethod(graphDataType);
        descrializeGenericMethod.Invoke(null, new object[] { graphDataInstance, textGraph, null, false });

        // graphObject.graph.OnEnable();
        graphDataType.GetMethod("OnEnable")!.Invoke(graphDataInstance, null);

        // graphObject.graph.ValidateGraph();
        graphDataType.GetMethod("ValidateGraph")!.Invoke(graphDataInstance, null);

        // return graphData.graph
        return graphDataInstance;
    }

    private static string GenerateShaderCode(string shaderAssetPath, string shaderName = null)
    {
        Type generatorType =
            Type.GetType("UnityEditor.ShaderGraph.Generator, Unity.ShaderGraph.Editor")!;
        Type modeType =
            Type.GetType("UnityEditor.ShaderGraph.GenerationMode, Unity.ShaderGraph.Editor")!;

        shaderName ??= Path.GetFileNameWithoutExtension(shaderAssetPath);

        object graphData = GetGraphData(shaderAssetPath);

        // new Generator(graphData, null, GenerationMode.ForReals, assetName, target:null, assetCollection:null, humanReadable: true);
        object forReals = ((FieldInfo)modeType.GetMember("ForReals")[0]).GetValue(null);
        object generator = Activator.CreateInstance(
            generatorType,
            new object[] { graphData, null, forReals, shaderName, null, null, true }
        );
        object shaderCode = generatorType
            .GetProperty("generatedShader", BindingFlags.Public | BindingFlags.Instance)!
            .GetValue(generator);

        return (string)shaderCode;
    }
1 Like
7

For your problem,the best way to do may be just to adjust the shadergraph template i guess.