public override void OnImportAsset(AssetImportContext ctx)
{
var importLog = new ShaderGraphImporter.AssetImportErrorLog(ctx);
var graphAsset = ScriptableObject.CreateInstance <SubGraphAsset>();
var subGraphPath = ctx.assetPath;
var subGraphGuid = AssetDatabase.AssetPathToGUID(subGraphPath);
graphAsset.assetGuid = subGraphGuid;
var textGraph = File.ReadAllText(subGraphPath, Encoding.UTF8);
var messageManager = new MessageManager();
var graphData = new GraphData
{
isSubGraph = true,
assetGuid = subGraphGuid,
messageManager = messageManager
};
MultiJson.Deserialize(graphData, textGraph);
try
{
ProcessSubGraph(graphAsset, graphData, importLog);
}
catch (Exception e)
{
graphAsset.isValid = false;
Debug.LogException(e, graphAsset);
}
finally
{
var errors = messageManager.ErrorStrings((nodeId) => NodeWasUsedByGraph(nodeId, graphData));
int errCount = errors.Count();
if (errCount > 0)
{
var firstError = errors.FirstOrDefault();
importLog.LogError($"Sub Graph at {subGraphPath} has {errCount} error(s), the first is: {firstError}", graphAsset);
graphAsset.isValid = false;
}
else
{
var warnings = messageManager.ErrorStrings((nodeId) => NodeWasUsedByGraph(nodeId, graphData), Rendering.ShaderCompilerMessageSeverity.Warning);
int warningCount = warnings.Count();
if (warningCount > 0)
{
var firstWarning = warnings.FirstOrDefault();
importLog.LogWarning($"Sub Graph at {subGraphPath} has {warningCount} warning(s), the first is: {firstWarning}", graphAsset);
}
}
messageManager.ClearAll();
}
Texture2D texture = Resources.Load <Texture2D>("Icons/sg_subgraph_icon");
ctx.AddObjectToAsset("MainAsset", graphAsset, texture);
ctx.SetMainObject(graphAsset);
var metadata = ScriptableObject.CreateInstance <ShaderSubGraphMetadata>();
metadata.hideFlags = HideFlags.HideInHierarchy;
metadata.assetDependencies = new List <UnityEngine.Object>();
AssetCollection assetCollection = new AssetCollection();
MinimalGraphData.GatherMinimalDependenciesFromFile(assetPath, assetCollection);
foreach (var asset in assetCollection.assets)
{
if (asset.Value.HasFlag(AssetCollection.Flags.IncludeInExportPackage))
{
// this sucks that we have to fully load these assets just to set the reference,
// which then gets serialized as the GUID that we already have here. :P
var dependencyPath = AssetDatabase.GUIDToAssetPath(asset.Key);
if (!string.IsNullOrEmpty(dependencyPath))
{
metadata.assetDependencies.Add(
AssetDatabase.LoadAssetAtPath(dependencyPath, typeof(UnityEngine.Object)));
}
}
}
ctx.AddObjectToAsset("Metadata", metadata);
// declare dependencies
foreach (var asset in assetCollection.assets)
{
if (asset.Value.HasFlag(AssetCollection.Flags.SourceDependency))
{
ctx.DependsOnSourceAsset(asset.Key);
// I'm not sure if this warning below is actually used or not, keeping it to be safe
var assetPath = AssetDatabase.GUIDToAssetPath(asset.Key);
// Ensure that dependency path is relative to project
if (!string.IsNullOrEmpty(assetPath) && !assetPath.StartsWith("Packages/") && !assetPath.StartsWith("Assets/"))
{
importLog.LogWarning($"Invalid dependency path: {assetPath}", graphAsset);
}
}
// NOTE: dependencies declared by GatherDependenciesFromSourceFile are automatically registered as artifact dependencies
// HOWEVER: that path ONLY grabs dependencies via MinimalGraphData, and will fail to register dependencies
// on GUIDs that don't exist in the project. For both of those reasons, we re-declare the dependencies here.
if (asset.Value.HasFlag(AssetCollection.Flags.ArtifactDependency))
{
ctx.DependsOnArtifact(asset.Key);
}
}
}
static void ProcessSubGraph(SubGraphAsset asset, GraphData graph, ShaderGraphImporter.AssetImportErrorLog importLog)
{
var graphIncludes = new IncludeCollection();
var registry = new FunctionRegistry(new ShaderStringBuilder(), graphIncludes, true);
asset.functions.Clear();
asset.isValid = true;
graph.OnEnable();
graph.messageManager.ClearAll();
graph.ValidateGraph();
var assetPath = AssetDatabase.GUIDToAssetPath(asset.assetGuid);
asset.hlslName = NodeUtils.GetHLSLSafeName(Path.GetFileNameWithoutExtension(assetPath));
asset.inputStructName = $"Bindings_{asset.hlslName}_{asset.assetGuid}_$precision";
asset.functionName = $"SG_{asset.hlslName}_{asset.assetGuid}_$precision";
asset.path = graph.path;
var outputNode = graph.outputNode;
var outputSlots = PooledList <MaterialSlot> .Get();
outputNode.GetInputSlots(outputSlots);
List <AbstractMaterialNode> nodes = new List <AbstractMaterialNode>();
NodeUtils.DepthFirstCollectNodesFromNode(nodes, outputNode);
// flag the used nodes so we can filter out errors from unused nodes
foreach (var node in nodes)
{
node.SetUsedByGenerator();
}
// Start with a clean slate for the input/output capabilities and dependencies
asset.inputCapabilities.Clear();
asset.outputCapabilities.Clear();
asset.slotDependencies.Clear();
ShaderStageCapability effectiveShaderStage = ShaderStageCapability.All;
foreach (var slot in outputSlots)
{
var stage = NodeUtils.GetEffectiveShaderStageCapability(slot, true);
if (effectiveShaderStage == ShaderStageCapability.All && stage != ShaderStageCapability.All)
{
effectiveShaderStage = stage;
}
asset.outputCapabilities.Add(new SlotCapability {
slotName = slot.RawDisplayName(), capabilities = stage
});
// Find all unique property nodes used by this slot and record a dependency for this input/output pair
var inputPropertyNames = new HashSet <string>();
var nodeSet = new HashSet <AbstractMaterialNode>();
NodeUtils.CollectNodeSet(nodeSet, slot);
foreach (var node in nodeSet)
{
if (node is PropertyNode propNode && !inputPropertyNames.Contains(propNode.property.displayName))
{
inputPropertyNames.Add(propNode.property.displayName);
var slotDependency = new SlotDependencyPair();
slotDependency.inputSlotName = propNode.property.displayName;
slotDependency.outputSlotName = slot.RawDisplayName();
asset.slotDependencies.Add(slotDependency);
}
}
}
CollectInputCapabilities(asset, graph);
asset.vtFeedbackVariables = VirtualTexturingFeedbackUtils.GetFeedbackVariables(outputNode as SubGraphOutputNode);
asset.requirements = ShaderGraphRequirements.FromNodes(nodes, effectiveShaderStage, false);
// output precision is whatever the output node has as a graph precision, falling back to the graph default
asset.outputGraphPrecision = outputNode.graphPrecision.GraphFallback(graph.graphDefaultPrecision);
// this saves the graph precision, which indicates whether this subgraph is switchable or not
asset.subGraphGraphPrecision = graph.graphDefaultPrecision;
asset.previewMode = graph.previewMode;
asset.includes = graphIncludes;
GatherDescendentsFromGraph(new GUID(asset.assetGuid), out var containsCircularDependency, out var descendents);
asset.descendents.AddRange(descendents.Select(g => g.ToString()));
asset.descendents.Sort(); // ensure deterministic order
var childrenSet = new HashSet <string>();
var anyErrors = false;
foreach (var node in nodes)
{
if (node is SubGraphNode subGraphNode)
{
var subGraphGuid = subGraphNode.subGraphGuid;
childrenSet.Add(subGraphGuid);
}
if (node.hasError)
{
anyErrors = true;
}
asset.children = childrenSet.ToList();
asset.children.Sort(); // ensure deterministic order
}
if (!anyErrors && containsCircularDependency)
{
importLog.LogError($"Error in Graph at {assetPath}: Sub Graph contains a circular dependency.", asset);
anyErrors = true;
}
if (anyErrors)
{
asset.isValid = false;
registry.ProvideFunction(asset.functionName, sb => { });
return;
}
foreach (var node in nodes)
{
if (node is IGeneratesFunction generatesFunction)
{
registry.builder.currentNode = node;
generatesFunction.GenerateNodeFunction(registry, GenerationMode.ForReals);
}
}
// Need to order the properties so that they are in the same order on a subgraph node in a shadergraph
// as they are in the blackboard for the subgraph itself. The (blackboard) categories keep that ordering,
// so traverse those and add those items to the ordered properties list. Needs to be used to set up the
// function _and_ to write out the final asset data so that the function call parameter order matches as well.
var orderedProperties = new List <AbstractShaderProperty>();
var propertiesList = graph.properties.ToList();
foreach (var category in graph.categories)
{
foreach (var child in category.Children)
{
var prop = propertiesList.Find(p => p.guid == child.guid);
// Not all properties in the category are actually on the graph.
// In particular, it seems as if keywords are not properties on sub-graphs.
if (prop != null)
{
orderedProperties.Add(prop);
}
}
}
// If we are importing an older file that has not had categories generated for it yet, include those now.
orderedProperties.AddRange(graph.properties.Except(orderedProperties));
// provide top level subgraph function
// NOTE: actual concrete precision here shouldn't matter, it's irrelevant when building the subgraph asset
registry.ProvideFunction(asset.functionName, asset.subGraphGraphPrecision, ConcretePrecision.Single, sb =>
{
GenerationUtils.GenerateSurfaceInputStruct(sb, asset.requirements, asset.inputStructName);
sb.AppendNewLine();
// Generate the arguments... first INPUTS
var arguments = new List <string>();
foreach (var prop in orderedProperties)
{
// apply fallback to the graph default precision (but don't convert to concrete)
// this means "graph switchable" properties will use the precision token
GraphPrecision propGraphPrecision = prop.precision.ToGraphPrecision(graph.graphDefaultPrecision);
string precisionString = propGraphPrecision.ToGenericString();
arguments.Add(prop.GetPropertyAsArgumentString(precisionString));
if (prop.isConnectionTestable)
{
arguments.Add($"bool {prop.GetConnectionStateHLSLVariableName()}");
}
}
{
var dropdowns = graph.dropdowns;
foreach (var dropdown in dropdowns)
{
arguments.Add($"int {dropdown.referenceName}");
}
}
// now pass surface inputs
arguments.Add(string.Format("{0} IN", asset.inputStructName));
// Now generate output arguments
foreach (MaterialSlot output in outputSlots)
{
arguments.Add($"out {output.concreteValueType.ToShaderString(asset.outputGraphPrecision.ToGenericString())} {output.shaderOutputName}_{output.id}");
}
// Vt Feedback output arguments (always full float4)
foreach (var output in asset.vtFeedbackVariables)
{
arguments.Add($"out {ConcreteSlotValueType.Vector4.ToShaderString(ConcretePrecision.Single)} {output}_out");
}
// Create the function prototype from the arguments
sb.AppendLine("void {0}({1})"
, asset.functionName
, arguments.Aggregate((current, next) => $"{current}, {next}"));
// now generate the function
using (sb.BlockScope())
{
// Just grab the body from the active nodes
foreach (var node in nodes)
{
if (node is IGeneratesBodyCode generatesBodyCode)
{
sb.currentNode = node;
generatesBodyCode.GenerateNodeCode(sb, GenerationMode.ForReals);
if (node.graphPrecision == GraphPrecision.Graph)
{
// code generated by nodes that use graph precision stays in generic form with embedded tokens
// those tokens are replaced when this subgraph function is pulled into a graph that defines the precision
}
else
{
sb.ReplaceInCurrentMapping(PrecisionUtil.Token, node.concretePrecision.ToShaderString());
}
}
}
foreach (var slot in outputSlots)
{
sb.AppendLine($"{slot.shaderOutputName}_{slot.id} = {outputNode.GetSlotValue(slot.id, GenerationMode.ForReals)};");
}
foreach (var slot in asset.vtFeedbackVariables)
{
sb.AppendLine($"{slot}_out = {slot};");
}
}
});
// save all of the node-declared functions to the subgraph asset
foreach (var name in registry.names)
{
var source = registry.sources[name];
var func = new FunctionPair(name, source.code, source.graphPrecisionFlags);
asset.functions.Add(func);
}
var collector = new PropertyCollector();
foreach (var node in nodes)
{
int previousPropertyCount = Math.Max(0, collector.propertyCount - 1);
node.CollectShaderProperties(collector, GenerationMode.ForReals);
// This is a stop-gap to prevent the autogenerated values from JsonObject and ShaderInput from
// resulting in non-deterministic import data. While we should move to local ids in the future,
// this will prevent cascading shader recompilations.
for (int i = previousPropertyCount; i < collector.propertyCount; ++i)
{
var prop = collector.GetProperty(i);
var namespaceId = node.objectId;
var nameId = prop.referenceName;
prop.OverrideObjectId(namespaceId, nameId + "_ObjectId_" + i);
prop.OverrideGuid(namespaceId, nameId + "_Guid_" + i);
}
}
asset.WriteData(orderedProperties, graph.keywords, graph.dropdowns, collector.properties, outputSlots, graph.unsupportedTargets);
outputSlots.Dispose();
}