Merge branch 'master' of github.com:Phyronnaz/HLSLMaterial

Author: Phyronnaz

README.md

@@ -1 +1,75 @@
-# HLSLMaterial
+# HLSL Material for Unreal Engine
+
+Ever wanted to write complex material functions directly in HLSL? Now you can!
+
+Unreal Engine 4.26, 4.27 and 5.0 are supported. 4.25 cannot be supported as custom nodes have a single output in that version.
+
+Demo: https://twitter.com/phyronnaz/status/1452553917204733953
+
+## Features
+* HLSL support: write all your functions in a single hlsl file and use any of them in regular materials
+* Team-friendly: regular material functions are generated, so your team members don't need the plugin to use them!
+* Live updates: material functions & opened material editors are refreshed when saving the hlsl file (Windows only)
+* Comment support: comments are parsed & pin tooltips are set accordingly
+
+## Installing from source
+Download the repo as a zip, and extract it under your project Plugins folder so you have `YourProject/Plugins/HLSLMaterial/HLSLMaterial.uplugin`
+
+## How to
+* Create a new `HLSL Material Function Library` (right click Content Browser -> Material & Textures). This asset will be the link between your hlsl file and all the generated material functions.
+* Set the `File` on it to point to your HLSL file
+* Add functions to the file
+* Material functions will be created when you save the HLSL file
+* You can also disable the automatic updates and manually right click the asset -> `Update from HLSL`
+
+## Syntax
+* All return types must be `void` to ensure the pins are all properly named
+* To mark a parameter as an output, use `out`: eg, `out float3 MyOutput`
+* Comments must use the `//` syntax, `/*` is not supported
+* `@param` in comments will be parsed & put into the pin tooltips
+
+```hlsl
+// Ray-sphere intersection
+// @param   RayOrigin       The origin of the ray
+// @param   RayDirection    The direction of the ray
+// @param   SphereCenter    The center of the sphere
+// @param   SphereRadius    The radius of the sphere
+// @param   Distance        The distance from the ray origin to the hit on the sphere
+void RaySphereIntersect(float3 RayOrigin, float3 RayDirection, float3 SphereCenter, float SphereRadius, out float Distance) 
+{
+    float a = dot(RayDirection, RayDirection);
+    float3 SphereCenterToRayOrigin = RayOrigin - SphereCenter;
+    float b = 2.0 * dot(RayDirection, SphereCenterToRayOrigin);
+    float c = dot(SphereCenterToRayOrigin, SphereCenterToRayOrigin) - (SphereRadius * SphereRadius);
+    float Discriminant = b * b - 4.0 * a* c;
+
+    if (Discriminant < 0.0) 
+    {
+        Distance = -1.0;
+    }
+    else
+    {
+      Distance = (-b - sqrt(Discriminant)) / 2 * a;
+    }
+}
+```
+
+## How it works
+
+The plugin manually parses the functions in the HLSL file. From there, it creates new material functions with a Custom node holding the function body.
+
+The logic is pretty simple & straightforward, so it should be relatively robust.
+
+## Project management
+### Moving functions
+Material functions are generated next to your library asset, under `YourFunctionLibraryAsset_Generated/`.
+Once they are generated, you should be able to move them anywhere - the library keeps a ref to them.
+
+### Renaming functions
+If you rename a function in your HLSL file, you need to manually rename the corresponding material function in Unreal, ideally before saving the HLSL. Otherwise, a new one will be created with the new name.
+
+### Deleting functions
+The plugin will never delete any asset. If you remove a function from the HLSL, it is up to you to remove it from Unreal.
+
+### Source Control
+You don't need to check in the HLSL file or the library - simply checking in the generated functions should be enough. However, if your teammates are also using the plugin it might be best to check in everything.

Source/HLSLMaterialEditor/Private/HLSLMaterialFunctionLibraryEditor.cpp

@@ -259,14 +259,17 @@ void FVoxelMaterialExpressionLibraryEditor::Generate(UHLSLMaterialFunctionLibrar
 		}
 	}
 
-	Library.MaterialFunctions.Remove(nullptr);
+	Library.MaterialFunctions.RemoveAll([&](TSoftObjectPtr<UMaterialFunction> InFunction)
+	{
+		return !InFunction.IsValid();
+	});
 
 	FMaterialUpdateContext UpdateContext;
 	for (FFunction Function : Functions)
 	{
 		TSoftObjectPtr<UMaterialFunction>* MaterialFunctionPtr = Library.MaterialFunctions.FindByPredicate([&](TSoftObjectPtr<UMaterialFunction> InFunction)
 		{
-			return InFunction->GetFName() == *Function.Name;
+			return ensure(InFunction) && InFunction->GetFName() == *Function.Name;
 		});
 		if (!MaterialFunctionPtr)
 		{
@@ -288,7 +291,7 @@ void FVoxelMaterialExpressionLibraryEditor::Generate(UHLSLMaterialFunctionLibrar
 
 		TMap<FName, FGuid> FunctionInputGuids;
 		TMap<FName, FGuid> FunctionOutputGuids;
-		for (auto* Expression : MaterialFunction->FunctionExpressions)
+		for (UMaterialExpression* Expression : MaterialFunction->FunctionExpressions)
 		{
 			if (UMaterialExpressionFunctionInput* FunctionInput = Cast<UMaterialExpressionFunctionInput>(Expression))
 			{