Outputs config : Add lpe preset for Arnold

Changes.md

@@ -13,7 +13,9 @@ Improvements
   - Added the ability to edit the scale of node icons.
   - Improved layout of Box node plug creator visibility toggles.
 - ArnoldShader : Moved the `toon` shader's `*_tonemap_hue_saturation` parameters to appropriate sections in the UI.
-- Arnold : Added `deep_alpha` and `deep_beauty` output presets demonstrating outputs that produce deep images.
+- Arnold :
+  - Added `deep_alpha` and `deep_beauty` output presets demonstrating outputs that produce deep images.
+  - Added `lpe` output preset demonstrating an output using a light path expression.
 
 API
 ---

startup/gui/outputs.py

@@ -120,6 +120,7 @@
 		"depth",
 		"deep_alpha",
 		"deep_beauty",
+		"lpe",
 	] :
 
 		label = aov.replace( "_", " " ).title().replace( " ", "_" )
@@ -129,6 +130,8 @@
 			data = "float Z"
 		elif aov == "normal":
 			data = "color N"
+		elif aov == "lpe" :
+			data = "lpe C.*"
 		else:
 			data = "color " + aov
 
@@ -142,7 +145,7 @@
 		if aov == "depth":
 			parameters["layerName"] = "Z"
 
-		if aov not in { "motionvector", "emission", "background", "deep_alpha" } :
+		if aov not in { "motionvector", "emission", "background", "deep_alpha", "lpe" } :
 			parameters["layerPerLightGroup"] = False
 
 		if aov.startswith( "deep_" ) :
@@ -164,6 +167,9 @@
 			}
 		)
 
+		if aov == "lpe" :
+			interactiveParameters["layerName"] = "lpe"
+
 		GafferScene.Outputs.registerOutput(
 			"Interactive/Arnold/" + label,
 			IECoreScene.Output(