From c41a446ae96bc1b74b9f8660c2859a0e1ab696c1 Mon Sep 17 00:00:00 2001
From: Wojciech Figat <wojtek@figat.pl>
Date: Mon, 28 Mar 2022 15:02:32 +0200
Subject: [PATCH] Add `Rotate Vector` node to Visject Surface graphs

---
 Source/Editor/Surface/Archetypes/Math.cs   | 14 ++++++++++++++
 Source/Engine/Visject/ShaderGraph.cpp      |  9 ++++++++-
 Source/Engine/Visject/ShaderGraphValue.cpp |  4 ++--
 Source/Engine/Visject/VisjectGraph.cpp     | 10 ++++++++--
 Source/Shaders/Common.hlsl                 |  2 +-
 5 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/Source/Editor/Surface/Archetypes/Math.cs b/Source/Editor/Surface/Archetypes/Math.cs
index 2bfb3e816..b9d4098bc 100644
--- a/Source/Editor/Surface/Archetypes/Math.cs
+++ b/Source/Editor/Surface/Archetypes/Math.cs
@@ -427,6 +427,20 @@ namespace FlaxEditor.Surface.Archetypes
                     NodeElementArchetype.Factory.Output(0, string.Empty, typeof(float), 4),
                 }
             },
+            new NodeArchetype
+            {
+                TypeID = 49,
+                Title = "Rotate Vector",
+                Description = "Rotates given vector using the Quaternion",
+                Flags = NodeFlags.AllGraphs,
+                Size = new Vector2(200, 40),
+                Elements = new[]
+                {
+                    NodeElementArchetype.Factory.Input(0, "Quaternion", true, typeof(Quaternion), 0),
+                    NodeElementArchetype.Factory.Input(1, "Vector", true, typeof(Vector3), 1),
+                    NodeElementArchetype.Factory.Output(0, string.Empty, typeof(Vector3), 2),
+                }
+            },
         };
     }
 }
diff --git a/Source/Engine/Visject/ShaderGraph.cpp b/Source/Engine/Visject/ShaderGraph.cpp
index d06a00977..11adc31cd 100644
--- a/Source/Engine/Visject/ShaderGraph.cpp
+++ b/Source/Engine/Visject/ShaderGraph.cpp
@@ -409,10 +409,17 @@ void ShaderGenerator::ProcessGroupMath(Box* box, Node* node, Value& value)
         const auto rangeA = tryGetValue(node->GetBox(1), node->Values[1].AsVector2());
         const auto rangeB = tryGetValue(node->GetBox(2), node->Values[2].AsVector2());
         const auto clamp  = tryGetValue(node->GetBox(3), node->Values[3]).AsBool();
-
         const auto mapFunc = String::Format(TEXT("{2}.x + ({0} - {1}.x) * ({2}.y - {2}.x) / ({1}.y - {1}.x)"), inVal.Value, rangeA.Value, rangeB.Value);
         value = writeLocal(ValueType::Float, String::Format(TEXT("{2} ? clamp({0}, {1}.x, {1}.y) : {0}"), mapFunc, rangeB.Value, clamp.Value), node);
         break;
+    }
+        // Rotate Vector
+    case 49:
+    {
+        const Value quaternion = tryGetValue(node->GetBox(0), Value::InitForZero(VariantType::Quaternion)).Cast(VariantType::Quaternion);
+        const Value vector = tryGetValue(node->GetBox(1), Vector3::Forward).Cast(VariantType::Vector3);
+        value = writeLocal(ValueType::Vector3, String::Format(TEXT("QuatRotateVector({0}, {1})"), quaternion.Value, vector.Value), node);
+        break;
     }
     default:
         break;
diff --git a/Source/Engine/Visject/ShaderGraphValue.cpp b/Source/Engine/Visject/ShaderGraphValue.cpp
index 828f9ac0f..0b4178ca3 100644
--- a/Source/Engine/Visject/ShaderGraphValue.cpp
+++ b/Source/Engine/Visject/ShaderGraphValue.cpp
@@ -130,7 +130,7 @@ ShaderGraphValue ShaderGraphValue::InitForZero(VariantType::Types type)
         CRASH;
         v = nullptr;
     }
-    return ShaderGraphValue(type, String(v));
+    return ShaderGraphValue(type, v);
 }
 
 ShaderGraphValue ShaderGraphValue::InitForHalf(VariantType::Types type)
@@ -309,7 +309,7 @@ ShaderGraphValue ShaderGraphValue::Cast(const ShaderGraphValue& v, VariantType::
             format = TEXT("{0}.xyz");
             break;
         case VariantType::Types::Quaternion:
-            format = TEXT("QuatRotateVector(float3(0, 0, 1), {0})");
+            format = TEXT("QuatRotateVector({0}, float3(0, 0, 1))"); // Returns direction vector
             break;
         }
         break;
diff --git a/Source/Engine/Visject/VisjectGraph.cpp b/Source/Engine/Visject/VisjectGraph.cpp
index e2091e749..658121b20 100644
--- a/Source/Engine/Visject/VisjectGraph.cpp
+++ b/Source/Engine/Visject/VisjectGraph.cpp
@@ -405,11 +405,17 @@ void VisjectExecutor::ProcessGroupMath(Box* box, Node* node, Value& value)
         const Vector2 rangeA = tryGetValue(node->GetBox(1), node->Values[1]).AsVector2();
         const Vector2 rangeB = tryGetValue(node->GetBox(2), node->Values[2]).AsVector2();
         const bool clamp = tryGetValue(node->GetBox(3), node->Values[3]).AsBool;
-
         auto mapFunc = Math::Remap(inVal, rangeA.X, rangeA.Y, rangeB.X, rangeB.Y);
-
         value = clamp ? Math::Clamp(mapFunc, rangeB.X, rangeB.Y) : mapFunc;
         break;
+    }
+        // Rotate Vector
+    case 49:
+    {
+        const Quaternion quaternion = (Quaternion)tryGetValue(node->GetBox(0), Quaternion::Identity);
+        const Vector3 vector = (Vector3)tryGetValue(node->GetBox(1), Vector3::Forward);
+        value = quaternion * vector;
+        break;
     }
     default:
         break;
diff --git a/Source/Shaders/Common.hlsl b/Source/Shaders/Common.hlsl
index 8e5a682c6..fd5fc19f4 100644
--- a/Source/Shaders/Common.hlsl
+++ b/Source/Shaders/Common.hlsl
@@ -211,7 +211,7 @@ float4 QuatMultiply(float4 q1, float4 q2)
 }
 
 // Vector rotation with a quaternion (http://mathworld.wolfram.com/Quaternion.html)
-float3 QuatRotateVector(float3 v, float4 q)
+float3 QuatRotateVector(float4 q, float3 v)
 {
     float4 nq = q * float4(-1, -1, -1, 1);
     return QuatMultiply(q, QuatMultiply(float4(v, 0), nq)).xyz;