Mermaid graphing util for ShaderGraphs.

.github/workflows/main.yml

@@ -247,6 +247,7 @@ jobs:
         python Scripts/generateshader.py ../resources/Materials/Examples/StandardSurface --target mdl
         python Scripts/generateshader.py ../resources/Materials/Examples/StandardSurface --target msl
         python Scripts/generateshader.py ../resources/Materials/Examples/StandardSurface --target slang
+        python Scripts/generateshader.py ../resources/Materials/Examples/StandardSurface --graph --graphValues
       working-directory: python
 
     - name: Shader Validation Tests (Windows)

python/Scripts/generateshader.py

@@ -53,6 +53,8 @@ def main():
     parser.add_argument('--validatorArgs', dest='validatorArgs', nargs='?', const=' ', type=str, help='Optional arguments for code validator.')
     parser.add_argument('--vulkanGlsl', dest='vulkanCompliantGlsl', default=False, type=bool, help='Set to True to generate Vulkan-compliant GLSL when using the genglsl target.')
     parser.add_argument('--shaderInterfaceType', dest='shaderInterfaceType', default=0, type=int, help='Set the type of shader interface to be generated')
+    parser.add_argument('--graph', dest='graph', action='store_true', help='Set to True to generate a Mermaid graph of the shader graph for each shader.')
+    parser.add_argument('--graphValues', dest='graphValues', action='store_true', help='Set to True to output input values for Mermaid graphs.')
     parser.add_argument(dest='inputFilename', help='Path to input document or folder containing input documents.')
     opts = parser.parse_args()
 
@@ -156,6 +158,17 @@ def main():
             elemName = mx.createValidName(elemName)
             shader = shadergen.generate(elemName, elem, context)        
             if shader:
+                # Generate a Mermaid graph of the shader graph if requested
+                if opts.graph:
+                    graphValues = opts.graphValues == True
+                    mermaidGraph = shader.createMermaidGraph(graphValues)
+                    mermaidGraph = "```mermaid\n" + mermaidGraph + "\n```"
+                    filename = pathPrefix + "/" + shader.getName() + "." + gentarget + ".md"
+                    print('--- Wrote Mermaid graph to: ' + filename)
+                    file = open(filename, 'w+')
+                    file.write(mermaidGraph)
+                    file.close()
+
                 # Use extension of .vert and .frag as it's type is
                 # recognized by glslangValidator
                 if gentarget in ['glsl', 'essl', 'vulkan', 'msl', 'wgsl']:

source/JsMaterialX/JsMaterialXGenShader/JsShader.cpp

@@ -19,5 +19,6 @@ EMSCRIPTEN_BINDINGS(Shader)
         .smart_ptr<std::shared_ptr<mx::Shader>>("ShaderPtr")
         .function("getSourceCode", &mx::Shader::getSourceCode)
         .function("getStage", PTR_RETURN_OVERLOAD(mx::ShaderStage& (mx::Shader::*)(const std::string&), &mx::Shader::getStage), ems::allow_raw_pointers())
+        .function("createMermaidGraph", &mx::Shader::createMermaidGraph)
         ;
 }

source/MaterialXGenShader/Shader.cpp

@@ -67,4 +67,9 @@ ShaderStagePtr Shader::createStage(const string& name, ConstSyntaxPtr syntax)
     return s;
 }
 
+string Shader::createMermaidGraph(bool showInputValues) const
+{
+    return _graph ? _graph->createMermaidGraph(showInputValues) : string();
+}
+
 MATERIALX_NAMESPACE_END

source/MaterialXGenShader/Shader.h

@@ -100,6 +100,11 @@ class MX_GENSHADER_API Shader
     /// Return the shader source code for a given shader stage.
     const string& getSourceCode(const string& stage = Stage::PIXEL) const { return getStage(stage).getSourceCode(); }
 
+    /// Generate a Mermaid graph representing the shader graph and its nodes.
+    /// @param showInputValues If true, the graph will include the values of any unconnected input sockets
+    /// @return Mermaid graph as a string.
+    string createMermaidGraph(bool showInputValues) const;
+
   protected:
     /// Create a new stage in the shader.
     ShaderStagePtr createStage(const string& name, ConstSyntaxPtr syntax);

source/MaterialXGenShader/ShaderGraph.cpp

@@ -1308,6 +1308,58 @@ void ShaderGraph::populateUnitTransformMap(UnitSystemPtr unitSystem, ShaderPort*
     }
 }
 
+string ShaderGraph::createMermaidGraph(bool showInputValues) const
+{
+    std::ostringstream oss;
+    oss << "graph LR\n";
+
+    // Emit nodes
+    for (const ShaderNode* node : getNodes())
+    {
+        const string& id  = node->getUniqueId();
+        oss << "    " << id << "[\"" << id << "\"]\n";
+    }
+
+    for (const ShaderNode* node : getNodes())
+    {
+        const string& nodeId = node->getUniqueId();
+
+        // Emit connections
+        for (const ShaderOutput* output : node->getOutputs())
+        {
+            const ShaderInputVec& connections = output->getConnections();
+            for (const ShaderInput* input : connections)
+            {
+                if (input && input->getNode())
+                {
+                    const string connector = " --\"" + output->getName() + " --> " + input->getName() + "\"--> ";
+                    oss << "    " << nodeId << connector << input->getNode()->getUniqueId() << "\n";
+                }
+            }
+        }
+
+        // Optionally emit input values
+        if (showInputValues)
+        {
+            for (const ShaderInput* input : node->getInputs())
+            {
+                if (input)
+                {
+                    const string& valueString = input->getValueString();
+                    if (!valueString.empty())
+                    {
+                        oss << "    " << node->getUniqueId() << "/" << input->getName();
+                        oss <<  "[\""  << input->getName() << " = " << valueString << "\"]";
+                        oss << " --> " << nodeId << "\n";
+                    }
+                }
+            }
+        }
+    }   
+
+    return oss.str();
+}
+
 namespace
 {
 static const ShaderGraphEdgeIterator NULL_EDGE_ITERATOR(nullptr);

source/MaterialXGenShader/ShaderGraph.h

@@ -70,6 +70,11 @@ class MX_GENSHADER_API ShaderGraph : public ShaderNode
     /// Get a vector of all nodes in order
     const vector<ShaderNode*>& getNodes() const { return _nodeOrder; }
 
+    /// Generate a Mermaid graph representing this shader graph.
+    /// @param showInputValues If true, the graph will include the values of any unconnected input sockets 
+    /// @return Mermaid graph as a string.
+    string createMermaidGraph(bool showInputValues) const;
+
     /// Get number of input sockets
     size_t numInputSockets() const { return numOutputs(); }
 

source/PyMaterialX/PyMaterialXGenShader/PyShader.cpp

@@ -28,5 +28,6 @@ void bindPyShader(py::module& mod)
         .def("hasAttribute", &mx::Shader::hasAttribute)
         .def("getAttribute", &mx::Shader::getAttribute)
         .def("setAttribute", static_cast<void (mx::Shader::*)(const std::string&)>(&mx::Shader::setAttribute))
-        .def("setAttribute", static_cast<void (mx::Shader::*)(const std::string&, mx::ValuePtr)>(&mx::Shader::setAttribute));
+        .def("setAttribute", static_cast<void (mx::Shader::*)(const std::string&, mx::ValuePtr)>(&mx::Shader::setAttribute))
+        .def("createMermaidGraph", &mx::Shader::createMermaidGraph);
 }