[Backport 6000.3] Fixed generated code for preview nodes for UI Toolkit shaders

alexandret-unity · Evergreen · commit c0be1c9eb7a5 · 2026-03-11T10:06:52.000Z
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementLayoutUVNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementLayoutUVNode.cs
@@ -1,12 +1,13 @@
 using UnityEditor.Graphing;
 using UnityEditor.Rendering.UITK.ShaderGraph;
+using UnityEditor.ShaderGraph.Internal;
 using UnityEngine;
 
 namespace UnityEditor.ShaderGraph
 {
     [Title("Input", "UI", "Element Layout UV")]
     [SubTargetFilter(typeof(IUISubTarget))]
-    class ElementLayoutUV : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK
+    class ElementLayoutUV : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK, IMayRequireMeshUV
     {
         public const int LayoutUVSlotId = 0;
 
@@ -29,12 +30,25 @@ public override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
-            if (GetInputNodeFromSlot(LayoutUVSlotId) != null) sb.AppendLine(string.Format("$precision2 {0} = IN.layoutUV.xy;", GetVariableNameForSlot(LayoutUVSlotId)));
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode, use standard mesh UV0 (will visualize as color: red = u, green = v)
+                sb.AppendLine("$precision2 {0} = IN.uv0.xy;", GetVariableNameForSlot(LayoutUVSlotId));
+                return;
+            }
+
+            if (GetInputNodeFromSlot(LayoutUVSlotId) != null) sb.AppendLine("$precision2 {0} = IN.layoutUV.xy;", GetVariableNameForSlot(LayoutUVSlotId));
         }
 
         public bool RequiresUITK(ShaderStageCapability stageCapability)
         {
             return true;
         }
+
+        public bool RequiresMeshUV(UVChannel channel, ShaderStageCapability stageCapability)
+        {
+            // Require UV0 in preview mode for visualization
+            return channel == UVChannel.UV0;
+        }
     }
 }
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementTextureSizeNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementTextureSizeNode.cs
@@ -39,6 +39,16 @@ public override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode, return default values (1.0)
+                if (GetInputNodeFromSlot(TextureWidthSlotId) != null) sb.AppendLine("$precision1 {0} = 1.0;", GetVariableNameForSlot(TextureWidthSlotId));
+                if (GetInputNodeFromSlot(TextureHeightSlotId) != null) sb.AppendLine("$precision1 {0} = 1.0;", GetVariableNameForSlot(TextureHeightSlotId));
+                if (GetInputNodeFromSlot(TexelWidthSlotId) != null) sb.AppendLine("$precision1 {0} = 1.0;", GetVariableNameForSlot(TexelWidthSlotId));
+                if (GetInputNodeFromSlot(TexelHeightSlotId) != null) sb.AppendLine("$precision1 {0} = 1.0;", GetVariableNameForSlot(TexelHeightSlotId));
+                return;
+            }
+
             if ((GetInputNodeFromSlot(TextureWidthSlotId) != null) ||
                 (GetInputNodeFromSlot(TextureHeightSlotId) != null) ||
                 (GetInputNodeFromSlot(TexelWidthSlotId) != null) ||
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementTextureUVNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/Input/UI/ElementTextureUVNode.cs
@@ -1,12 +1,13 @@
 using UnityEditor.Graphing;
 using UnityEditor.Rendering.UITK.ShaderGraph;
+using UnityEditor.ShaderGraph.Internal;
 using UnityEngine;
 
 namespace UnityEditor.ShaderGraph
 {
     [Title("Input", "UI", "Element Texture UV")]
     [SubTargetFilter(typeof(IUISubTarget))]
-    class ElementTextureUVNode : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK
+    class ElementTextureUVNode : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK, IMayRequireMeshUV
     {
         public const int TextureUVSlotId = 0;
 
@@ -29,12 +30,25 @@ public override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
-            if (GetInputNodeFromSlot(TextureUVSlotId) != null) sb.AppendLine(string.Format("$precision2 {0} = IN.uvClip.xy;", GetVariableNameForSlot(TextureUVSlotId)));
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode, use standard mesh UV0 (will visualize as color: red = u, green = v)
+                sb.AppendLine("$precision2 {0} = IN.uv0.xy;", GetVariableNameForSlot(TextureUVSlotId));
+                return;
+            }
+
+            if (GetInputNodeFromSlot(TextureUVSlotId) != null) sb.AppendLine("$precision2 {0} = IN.uvClip.xy;", GetVariableNameForSlot(TextureUVSlotId));
         }
 
         public bool RequiresUITK(ShaderStageCapability stageCapability)
         {
             return true;
         }
+
+        public bool RequiresMeshUV(UVChannel channel, ShaderStageCapability stageCapability)
+        {
+            // Require UV0 in preview mode for visualization
+            return channel == UVChannel.UV0;
+        }
     }
 }
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultBitmapTextNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultBitmapTextNode.cs
@@ -33,7 +33,15 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
         {
             string outputVarName = GetVariableNameForSlot(k_OutputSlotId);
 
-            sb.AppendLine("float4 {0} = float4(1, 1, 0, 1);", outputVarName);
+            sb.AppendLine("float4 {0} = float4(1, 1, 1, 1);", outputVarName);
+
+            if (generationMode == GenerationMode.Preview)
+            {
+                bool hasTint = GetInputNodeFromSlot(k_InputSlotIdTint) != null;
+                if (hasTint)
+                    sb.AppendLine("{0} = {1};", outputVarName, GetSlotValue(k_InputSlotIdTint, generationMode));
+                return;
+            }
 
             sb.AppendLine("[branch] if ((_UIE_RENDER_TYPE_TEXT || _UIE_RENDER_TYPE_ANY) && round(IN.typeTexSettings.x) == k_FragTypeText && (!(GetTextureInfo(IN.typeTexSettings.y).sdfScale > 0.0)))");
             using (sb.BlockScope())
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultGradientNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultGradientNode.cs
@@ -29,7 +29,10 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
         {
             string outputVarName = GetVariableNameForSlot(k_OutputSlotId);
 
-            sb.AppendLine("float4 {0} = float4(1, 1, 0, 1);", outputVarName);
+            sb.AppendLine("float4 {0} = float4(1, 1, 1, 1);", outputVarName);
+
+            if (generationMode == GenerationMode.Preview)
+                return;
 
             sb.AppendLine("[branch] if (_UIE_RENDER_TYPE_GRADIENT || _UIE_RENDER_TYPE_ANY && round(IN.typeTexSettings.x) == k_FragTypeSvgGradient)");
             using (sb.BlockScope())
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultSDFTextNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultSDFTextNode.cs
@@ -33,7 +33,15 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
         {
             string outputVarName = GetVariableNameForSlot(k_OutputSlotId);
 
-            sb.AppendLine("float4 {0} = float4(1, 1, 0, 1);", outputVarName);
+            sb.AppendLine("float4 {0} = float4(1, 1, 1, 1);", outputVarName);
+
+            if (generationMode == GenerationMode.Preview)
+            {
+                bool hasTint = GetInputNodeFromSlot(k_InputSlotIdTint) != null;
+                if (hasTint)
+                    sb.AppendLine("{0} = {1};", outputVarName, GetSlotValue(k_InputSlotIdTint, generationMode));
+                return;
+            }
 
             sb.AppendLine("[branch] if ((_UIE_RENDER_TYPE_TEXT || _UIE_RENDER_TYPE_ANY) && round(IN.typeTexSettings.x) == k_FragTypeText && (GetTextureInfo(IN.typeTexSettings.y).sdfScale > 0.0))");
             using (sb.BlockScope())
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultSolidNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultSolidNode.cs
@@ -29,7 +29,10 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
         {
             string outputVarName = GetVariableNameForSlot(k_OutputSlotId);
 
-            sb.AppendLine("float4 {0} = float4(1, 1, 0, 1);", outputVarName);
+            sb.AppendLine("float4 {0} = float4(1, 1, 1, 1);", outputVarName);
+
+            if (generationMode == GenerationMode.Preview)
+                return;
 
             sb.AppendLine("[branch] if (_UIE_RENDER_TYPE_SOLID || _UIE_RENDER_TYPE_ANY && round(IN.typeTexSettings.x) == k_FragTypeSolid)");
             using (sb.BlockScope())
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultTextureNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/DefaultTextureNode.cs
@@ -36,7 +36,15 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
         {
             string outputVarName = GetVariableNameForSlot(k_OutputSlotId);
 
-            sb.AppendLine("float4 {0} = float4(1, 1, 0, 1);", outputVarName);
+            sb.AppendLine("float4 {0} = float4(1, 1, 1, 1);", outputVarName);
+
+            if (generationMode == GenerationMode.Preview)
+            {
+                bool hasTint = GetInputNodeFromSlot(k_InputSlotIdTint) != null;
+                if (hasTint)
+                    sb.AppendLine("{0} = {1};", outputVarName, GetSlotValue(k_InputSlotIdTint, generationMode));
+                return;
+            }
 
             sb.AppendLine("[branch] if (_UIE_RENDER_TYPE_TEXTURE || _UIE_RENDER_TYPE_ANY && round(IN.typeTexSettings.x) == k_FragTypeTexture)");
             using (sb.BlockScope())
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/IsForcedGammaNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/IsForcedGammaNode.cs
@@ -26,6 +26,13 @@ public sealed override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode, return false by default
+                sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotId));
+                return;
+            }
+
             sb.AppendLine("bool {0} = _UIE_FORCE_GAMMA;", GetVariableNameForSlot(k_OutputSlotId));
         }
 
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/RenderTypeBranchNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/RenderTypeBranchNode.cs
@@ -49,9 +49,21 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
             string outputVarNameColor = GetVariableNameForSlot(k_OutputSlotIdColor);
             string outputVarNameAlpha = GetVariableNameForSlot(k_OutputSlotIdAlpha);
 
-            sb.AppendLine("float3 {0} = float3(0, 0, 0);", outputVarNameColor);
+            sb.AppendLine("float3 {0} = float3(1, 1, 1);", outputVarNameColor);
             sb.AppendLine("float {0} = 1.0;", outputVarNameAlpha);
 
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode the UITK render-type macros don't exist.
+                // Output the Solid input if connected.
+                if (GetInputNodeFromSlot(k_InputSlotIdSolid) != null)
+                {
+                    sb.AppendLine("{0} = {1}.rgb;", outputVarNameColor, GetSlotValue(k_InputSlotIdSolid, generationMode));
+                    sb.AppendLine("{0} = {1}.a;", outputVarNameAlpha, GetSlotValue(k_InputSlotIdSolid, generationMode));
+                }
+                return;
+            }
+
             sb.AppendLine("[branch] if (_UIE_RENDER_TYPE_SOLID || _UIE_RENDER_TYPE_ANY && TestType(IN.typeTexSettings.x, k_FragTypeSolid))");
             using (sb.BlockScope())
             {
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/RenderTypeNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/RenderTypeNode.cs
@@ -39,6 +39,18 @@ public sealed override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode the UITK render-type macros don't exist.
+                // Default to Solid render type.
+                sb.AppendLine("bool {0} = true;", GetVariableNameForSlot(k_OutputSlotIdSolid));
+                sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotIdTexture));
+                sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotIdSDFText));
+                sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotIdBitmapText));
+                sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotIdGradient));
+                return;
+            }
+
             sb.AppendLine("bool {0} = _UIE_RENDER_TYPE_SOLID || _UIE_RENDER_TYPE_ANY && round(IN.typeTexSettings.x) == k_FragTypeSolid;", GetVariableNameForSlot(k_OutputSlotIdSolid));
             sb.AppendLine("bool {0} = _UIE_RENDER_TYPE_TEXTURE || _UIE_RENDER_TYPE_ANY && round(IN.typeTexSettings.x) == k_FragTypeTexture;", GetVariableNameForSlot(k_OutputSlotIdTexture));
             sb.AppendLine("bool {0} = (_UIE_RENDER_TYPE_TEXT || _UIE_RENDER_TYPE_ANY) && round(IN.typeTexSettings.x) == k_FragTypeText && (GetTextureInfo(IN.typeTexSettings.y).sdfScale > 0.0);", GetVariableNameForSlot(k_OutputSlotIdSDFText));
diff --git a/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/SampleElementTextureNode.cs b/Packages/com.unity.shadergraph/Editor/Data/Nodes/UI/SampleElementTextureNode.cs
@@ -82,6 +82,16 @@ public void GenerateNodeFunction(FunctionRegistry registry, GenerationMode gener
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
+            if (generationMode == GenerationMode.Preview)
+            {
+                // In preview mode, return white
+                sb.AppendLine("$precision4 {0} = $precision4(1, 1, 1, 1);", GetVariableNameForSlot(Color0SlotId));
+                sb.AppendLine("$precision4 {0} = $precision4(1, 1, 1, 1);", GetVariableNameForSlot(Color1SlotId));
+                sb.AppendLine("$precision4 {0} = $precision4(1, 1, 1, 1);", GetVariableNameForSlot(Color2SlotId));
+                sb.AppendLine("$precision4 {0} = $precision4(1, 1, 1, 1);", GetVariableNameForSlot(Color3SlotId));
+                return;
+            }
+
             sb.AppendLine("$precision4 {0};", GetVariableNameForSlot(Color0SlotId));
             sb.AppendLine("$precision4 {0};", GetVariableNameForSlot(Color1SlotId));
             sb.AppendLine("$precision4 {0};", GetVariableNameForSlot(Color2SlotId));
diff --git a/Packages/com.unity.shadergraph/Editor/Drawing/PreviewManager.cs b/Packages/com.unity.shadergraph/Editor/Drawing/PreviewManager.cs
@@ -1402,7 +1402,9 @@ void CompileMasterNodeShader()
             // Skip generation for VFXTarget
             if (!m_Graph.isOnlyVFXTarget)
             {
-                var generator = new Generator(m_Graph, m_Graph.outputNode, GenerationMode.Preview, "Master");
+                // UITK shaders need ForReals mode to have access to UITK macros for proper rendering
+                var mode = prefersUITKPreview ? GenerationMode.ForReals : GenerationMode.Preview;
+                var generator = new Generator(m_Graph, m_Graph.outputNode, mode, "Master");
                 shaderData.shaderString = generator.generatedShader;
 
                 // record the blocks temporarily created for missing stack blocks

Original file line number	Diff line number	Diff line change
`@@ -1,12 +1,13 @@`
`1`	`1`	`using UnityEditor.Graphing;`
`2`	`2`	`using UnityEditor.Rendering.UITK.ShaderGraph;`
	`3`	`+using UnityEditor.ShaderGraph.Internal;`
`3`	`4`	`using UnityEngine;`
`4`	`5`
`5`	`6`	`namespace UnityEditor.ShaderGraph`
`6`	`7`	`{`
`7`	`8`	`[Title("Input", "UI", "Element Layout UV")]`
`8`	`9`	`[SubTargetFilter(typeof(IUISubTarget))]`
`9`		`- class ElementLayoutUV : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK`
	`10`	`+ class ElementLayoutUV : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireUITK, IMayRequireMeshUV`
`10`	`11`	`{`
`11`	`12`	`public const int LayoutUVSlotId = 0;`
`12`	`13`
`@@ -29,12 +30,25 @@ public override void UpdateNodeAfterDeserialization()`
`29`	`30`
`30`	`31`	`public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)`
`31`	`32`	`{`
`32`		`- if (GetInputNodeFromSlot(LayoutUVSlotId) != null) sb.AppendLine(string.Format("$precision2 {0} = IN.layoutUV.xy;", GetVariableNameForSlot(LayoutUVSlotId)));`
	`33`	`+ if (generationMode == GenerationMode.Preview)`
	`34`	`+ {`
	`35`	`+ // In preview mode, use standard mesh UV0 (will visualize as color: red = u, green = v)`
	`36`	`+ sb.AppendLine("$precision2 {0} = IN.uv0.xy;", GetVariableNameForSlot(LayoutUVSlotId));`
	`37`	`+ return;`
	`38`	`+ }`
	`39`	`+`
	`40`	`+ if (GetInputNodeFromSlot(LayoutUVSlotId) != null) sb.AppendLine("$precision2 {0} = IN.layoutUV.xy;", GetVariableNameForSlot(LayoutUVSlotId));`
`33`	`41`	`}`
`34`	`42`
`35`	`43`	`public bool RequiresUITK(ShaderStageCapability stageCapability)`
`36`	`44`	`{`
`37`	`45`	`return true;`
`38`	`46`	`}`
	`47`	`+`
	`48`	`+ public bool RequiresMeshUV(UVChannel channel, ShaderStageCapability stageCapability)`
	`49`	`+ {`
	`50`	`+ // Require UV0 in preview mode for visualization`
	`51`	`+ return channel == UVChannel.UV0;`
	`52`	`+ }`
`39`	`53`	`}`
`40`	`54`	`}`
Original file line number	Diff line number	Diff line change
`@@ -26,6 +26,13 @@ public sealed override void UpdateNodeAfterDeserialization()`
`26`	`26`
`27`	`27`	`public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)`
`28`	`28`	`{`
	`29`	`+ if (generationMode == GenerationMode.Preview)`
	`30`	`+ {`
	`31`	`+ // In preview mode, return false by default`
	`32`	`+ sb.AppendLine("bool {0} = false;", GetVariableNameForSlot(k_OutputSlotId));`
	`33`	`+ return;`
	`34`	`+ }`
	`35`	`+`
`29`	`36`	`sb.AppendLine("bool {0} = _UIE_FORCE_GAMMA;", GetVariableNameForSlot(k_OutputSlotId));`
`30`	`37`	`}`
`31`	`38`