From d7b9056d943615767523980e47d4bffb07ab8932 Mon Sep 17 00:00:00 2001
From: NoriteSC <53096989+NoriteSC@users.noreply.github.com>
Date: Wed, 4 Oct 2023 13:13:45 +0200
Subject: [PATCH] added AAStep and resolved stefnotch reviewe

---
 Source/Editor/Surface/Archetypes/Material.cs  | 27 ++++++++++++++++---
 .../MaterialGenerator.Material.cpp            | 24 ++++++++++++++---
 2 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/Source/Editor/Surface/Archetypes/Material.cs b/Source/Editor/Surface/Archetypes/Material.cs
index a0aa7d29f..8e5329d22 100644
--- a/Source/Editor/Surface/Archetypes/Material.cs
+++ b/Source/Editor/Surface/Archetypes/Material.cs
@@ -885,8 +885,8 @@ namespace FlaxEditor.Surface.Archetypes
             new NodeArchetype
             {
                 TypeID = 40,
-                Title = "Ratangle Mask",
-                Description = "Creates a Ratangle mask",
+                Title = "Rectangle Mask",
+                Description = "Creates a Rectangle mask",
                 Flags = NodeFlags.MaterialGraph,
                 Size = new Float2(150, 40),
                 ConnectionsHints = ConnectionsHint.Vector,
@@ -898,7 +898,7 @@ namespace FlaxEditor.Surface.Archetypes
                 Elements = new[]
                 {
                     NodeElementArchetype.Factory.Input(0, "UV", true, typeof(Float2), 0),
-                    NodeElementArchetype.Factory.Input(1, "Ratangle", true, typeof(Float2), 1),
+                    NodeElementArchetype.Factory.Input(1, "Rectangle", true, typeof(Float2), 1),
                     NodeElementArchetype.Factory.Output(0, string.Empty, typeof(float), 5),
                 }
             },
@@ -906,7 +906,7 @@ namespace FlaxEditor.Surface.Archetypes
             {
                 TypeID = 41,
                 Title = "FWidth",
-                Description = "Creates a Partial Derivatives (fwidth)",
+                Description = "Creates a partial derivative (fwidth)",
                 Flags = NodeFlags.MaterialGraph,
                 Size = new Float2(150, 20),
                 ConnectionsHints = ConnectionsHint.Vector,
@@ -920,6 +920,25 @@ namespace FlaxEditor.Surface.Archetypes
                     NodeElementArchetype.Factory.Output(0, string.Empty, typeof(float), 5),
                 }
             },
+            new NodeArchetype
+            {
+                TypeID = 42,
+                Title = "AAStep",
+                Description = "Smooth version of step",
+                Flags = NodeFlags.MaterialGraph,
+                Size = new Float2(150, 20),
+                ConnectionsHints = ConnectionsHint.Vector,
+                DefaultValues = new object[]
+                {
+                    1,
+                    0
+                },
+                Elements = new[]
+                {
+                    NodeElementArchetype.Factory.Input(0, "value", true, typeof(float), 0),
+                    NodeElementArchetype.Factory.Output(0, string.Empty, typeof(float), 5),
+                }
+            },
         };
     }
 }
diff --git a/Source/Engine/Tools/MaterialGenerator/MaterialGenerator.Material.cpp b/Source/Engine/Tools/MaterialGenerator/MaterialGenerator.Material.cpp
index c6d05ef48..0c8d0780e 100644
--- a/Source/Engine/Tools/MaterialGenerator/MaterialGenerator.Material.cpp
+++ b/Source/Engine/Tools/MaterialGenerator/MaterialGenerator.Material.cpp
@@ -523,11 +523,10 @@ void MaterialGenerator::ProcessGroupMaterial(Box* box, Node* node, Value& value)
     case 40:
     {
         const auto uv = tryGetValue(node->GetBox(0), getUVs).AsFloat2();
-        const auto ratangle = tryGetValue(node->GetBox(1), node->Values[1]).AsFloat2();
+        const auto rectangle = tryGetValue(node->GetBox(1), node->Values[1]).AsFloat2();
 
-        auto d      = writeLocal(ValueType::Float2, String::Format(TEXT("abs({0} * 2 - 1) - {1}"),uv.Value, ratangle.Value), node);
-        auto fwidth = writeLocal(ValueType::Float , String::Format(TEXT("abs(ddx({0})) + abs(ddy({0}))"), d.Value), node);
-        auto d2     = writeLocal(ValueType::Float2 , String::Format(TEXT("1 - {0} / {1}"), d.Value, fwidth.Value), node);
+        auto d      = writeLocal(ValueType::Float2, String::Format(TEXT("abs({0} * 2 - 1) - {1}"),uv.Value, rectangle.Value), node);
+        auto d2     = writeLocal(ValueType::Float2 , String::Format(TEXT("1 - {0} / fwidth({0})"), d.Value), node);
         value       = writeLocal(ValueType::Float , String::Format(TEXT("saturate(min({0}.x, {0}.y))"), d2.Value), node);
         break;
     }
@@ -538,6 +537,23 @@ void MaterialGenerator::ProcessGroupMaterial(Box* box, Node* node, Value& value)
         value =  writeLocal(ValueType::Float, String::Format(TEXT("abs(ddx({0})) + abs(ddy({0}))"), d.Value), node);
         break;
     }
+    //AAStep (smooth version of step)
+    case 42:
+    {
+        //source https://www.ronja-tutorials.com/post/046-fwidth/#a-better-step
+
+        const auto compValue = tryGetValue(node->GetBox(0), getUVs).AsFloat();
+        const auto gradient = tryGetValue(node->GetBox(1), node->Values[1]).AsFloat();
+
+        auto change = writeLocal(ValueType::Float, String::Format(TEXT("fwidth({0})"), gradient.Value), node);
+
+        //base the range of the inverse lerp on the change over two pixels
+        auto lowerEdge = writeLocal(ValueType::Float, String::Format(TEXT("{0} - {1})"), compValue.Value, change.Value), node);
+        auto upperEdge = writeLocal(ValueType::Float, String::Format(TEXT("{0} + {1})"), compValue.Value, change.Value), node);
+
+        //do the inverse interpolation and saturate it
+        value = writeLocal(ValueType::Float, String::Format(TEXT("saturate((({0} - {1}) / ({2} - {1})))"), gradient.Value, lowerEdge.Value, upperEdge.Value), node);
+    }
     default:
         break;
     }