add new front/back opacity node

nodes/materials/__init__.py

@@ -8,13 +8,14 @@
 from .. import LuxCoreNodeTree
 
 # Import all material nodes just so they get registered
-from .emission import LuxCoreNodeMatEmission
+from .carpaint import LuxCoreNodeMatCarpaint
 from .cloth import LuxCoreNodeMatCloth
+from .emission import LuxCoreNodeMatEmission
+from .frontbackopacity import LuxCoreNodeMatFrontBackOpacity
 from .glass import LuxCoreNodeMatGlass
 from .glossytranslucent import LuxCoreNodeMatGlossyTranslucent
 from .glossy2 import LuxCoreNodeMatGlossy2
 from .glossycoating import LuxCoreNodeMatGlossyCoating
-from .carpaint import LuxCoreNodeMatCarpaint
 from .matte import LuxCoreNodeMatMatte
 from .mattetranslucent import LuxCoreNodeMatMatteTranslucent
 from .metal import LuxCoreNodeMatMetal
@@ -82,6 +83,7 @@ def poll(cls, context):
         NodeItem("LuxCoreNodeMatCarpaint", label="Carpaint"),
         NodeItem("LuxCoreNodeMatCloth", label="Cloth"),
         NodeItem("LuxCoreNodeMatVelvet", label="Velvet"),
+        NodeItem("LuxCoreNodeMatFrontBackOpacity", label="Front/Back Opacity"),
     ]),
 
     LuxCoreNodeCategoryMaterial("LUXCORE_MATERIAL_TEXTURE", "Texture", items=[

nodes/materials/frontbackopacity.py

@@ -0,0 +1,27 @@
+from .. import LuxCoreNodeMaterial
+from ...utils import node as utils_node
+
+
+class LuxCoreNodeMatFrontBackOpacity(LuxCoreNodeMaterial):
+    """
+    Not a standalone material, but a node that offers
+    optional extra properties for all materials, to
+    avoid cluttering all other material nodes.
+    """
+    bl_label = "Front/Back Opacity"
+    bl_width_default = 160
+
+    def init(self, context):
+        self.add_input("LuxCoreSocketMaterial", "Material")
+        self.add_input("LuxCoreSocketFloat0to1", "Front Opacity", 1)
+        self.add_input("LuxCoreSocketFloat0to1", "Back Opacity", 1)
+
+        self.outputs.new("LuxCoreSocketMaterial", "Material")
+
+    def sub_export(self, exporter, props, luxcore_name=None, output_socket=None):
+        input_mat_name = utils_node.export_material_input(self.inputs["Material"], exporter, props, luxcore_name)
+        definitions = {
+            "transparency.front": self.inputs["Front Opacity"].export(exporter, props),
+            "transparency.back": self.inputs["Back Opacity"].export(exporter, props),
+        }
+        return self.create_props(props, definitions, input_mat_name)

utils/node.py

@@ -66,14 +66,15 @@ def draw_transmission_info(node, layout):
         layout.label("Transmitted: %.2f" % transmitted, icon=icons.INFO)
 
 
-def export_material_input(input, exporter, props):
-    material_name = input.export(exporter, props)
+def export_material_input(input, exporter, props, luxcore_name=None):
+    material_name = input.export(exporter, props, luxcore_name)
 
     if material_name:
         return material_name
     else:
         print("WARNING: No material linked on input", input.name, "of node", input.node.name)
-        luxcore_name = "__BLACK__"
+        if luxcore_name is None:
+            luxcore_name = "__BLACK__"
         props.Set(pyluxcore.Property("scene.materials.%s.type" % luxcore_name, "matte"))
         props.Set(pyluxcore.Property("scene.materials.%s.kd" % luxcore_name, [0, 0, 0]))
         return luxcore_name