[VFX] Undoing slider value change not updating float field

Author: julienamsellem

Packages/com.unity.visualeffectgraph/Editor/Controls/VFXSliderField.cs

@@ -76,7 +76,7 @@ public float ToScaled(float linearValue)
         }
     }
 
-    abstract class VFXBaseSliderField<T> : VisualElement, INotifyValueChanged<T>
+    abstract class VFXBaseSliderField<T> : VisualElement, IVFXNotifyValueChanged<T>
     {
         protected readonly Slider m_Slider;
         protected readonly TextValueField<T> m_Field;
@@ -160,6 +160,11 @@ public void SetValueWithoutNotify(T newValue)
             SetValueWithoutNotify(ValueToFloat(newValue), newValue);
         }
 
+        public void SetValueWithoutNotify(T newValue, bool force)
+        {
+            SetValueWithoutNotify(ValueToFloat(newValue), newValue, force);
+        }
+
         public T value
         {
             get => m_Value;

Packages/com.unity.visualeffectgraph/Editor/GraphView/Views/Properties/PropertyRM.cs

@@ -36,6 +36,10 @@ interface IPropertyRMProvider
         void EndLiveModification();
     }
 
+    interface IVFXNotifyValueChanged<T> : INotifyValueChanged<T>
+    {
+        void SetValueWithoutNotify(T typedNewValue, bool force = false);
+    }
 
     class SimplePropertyRMProvider<T> : IPropertyRMProvider
     {
@@ -253,7 +257,7 @@ public void Update()
             Profiler.EndSample();
             Profiler.EndSample();
         }
-        
+
         void UpdateExpandable()
         {
             if (IsExpandable())
@@ -617,7 +621,10 @@ public override void UpdateGUI(bool force)
                 try
                 {
                     var value = (U)System.Convert.ChangeType(m_Value, typeof(U));
-                    m_Field.SetValueWithoutNotify(value);
+                    if (m_Field is IVFXNotifyValueChanged<U> vfxNotifyValueChanged)
+                        vfxNotifyValueChanged.SetValueWithoutNotify(value, force);
+                    else
+                        m_Field.SetValueWithoutNotify(value);
                 }
                 catch (System.Exception ex)
                 {

Tests/SRPTests/Projects/VisualEffectGraph_HDRP/Assets/AllTests/Editor/Tests/PropertyRMTests.cs

@@ -0,0 +1,58 @@
+using System.Collections;
+using System.Linq;
+
+using NUnit.Framework;
+
+using UnityEditor.VFX.Operator;
+using UnityEditor.VFX.UI;
+using UnityEngine.TestTools;
+using UnityEngine.UIElements;
+using UnityEngine.VFX;
+
+namespace UnityEditor.VFX.Test
+{
+    [TestFixture]
+    public class PropertyRMTests
+    {
+        [UnityTest, Description("Covers UUM-92186")]
+        public IEnumerator Undo_SliderChange()
+        {
+            // Arrange
+            var graph = VFXTestCommon.MakeTemporaryGraph();
+            var noiseOperator = (Noise)VFXLibrary.GetOperators().First(x => x.modelType == typeof(Noise)).CreateInstance();
+            noiseOperator.GetInputSlot(3).value = 0f;
+            graph.AddChild(noiseOperator);
+            var path = AssetDatabase.GetAssetPath(graph);
+            AssetDatabase.ImportAsset(path);
+
+            var asset = AssetDatabase.LoadAssetAtPath<VisualEffectAsset>(path);
+            Assert.IsTrue(VisualEffectAssetEditor.OnOpenVFX(asset.GetInstanceID(), 0));
+            var window = VFXViewWindow.GetWindow(asset, true);
+            window.LoadAsset(asset, null);
+            window.Show();
+            yield return null;
+
+            // Find the Roughness slider UI
+            var operatorUI = window.graphView.Q<VFXOperatorUI>();
+            var roughnessSlider = operatorUI.Query<Slider>().Last();
+            Assert.NotNull(roughnessSlider);
+            var floatField = roughnessSlider.parent as FloatField;
+            Assert.NotNull(floatField);
+
+            // Act
+            Undo.IncrementCurrentGroup();
+            floatField.Focus();
+            roughnessSlider.value = 1f;
+            yield return null;
+
+            Assert.AreEqual(1f, noiseOperator.GetInputSlot(3).value);
+            Undo.PerformUndo();
+            yield return null;
+
+            // Assert
+            var value = (float)noiseOperator.GetInputSlot(3).value;
+            Assert.AreEqual(0f, value);
+            Assert.AreEqual(0f, floatField.value);
+        }
+    }
+}