fixed the composite material

tools/blender/mitsuba/export/__init__.py

@@ -45,7 +45,10 @@ class ParamSetItem(list):
 	
 	def to_string_ref(self):
 		if self.type == "reference_texture" or self.type == "reference_material":
-			return '\t\t<ref name="%s" id="%s"/>\n' % (self.name, self.value)
+			if self.name == "":
+				return '\t\t<ref id="%s"/>\n' % self.value
+			else:
+				return '\t\t<ref name="%s" id="%s"/>\n' % (self.name, self.value)
 		else:
 			return ""
 

tools/blender/mitsuba/properties/material.py

@@ -579,5 +579,10 @@ class mitsuba_mat_composite(declarative_property_group):
 
 	def get_params(self):
 		params = ParamSet()
+		weights = ""
+		for i in range(1,self.nElements+1):
+			weights += str(getattr(self, "mat%i_weight" % i)) + " "
+			params.add_reference('material', "mat%i" % i, getattr(self, "mat%i_name" % i))
+		params.add_string('weights', weights)
 		return params
 

tools/blender/mitsuba/ui/materials/composite.py

@@ -28,14 +28,28 @@ class ui_material_composite(mitsuba_material_sub, bpy.types.Panel):
 	display_property_groups = [
 		( ('material', 'mitsuba_material'), 'mitsuba_mat_composite' )
 	]
-		
+
 	def draw(self, context):
 		super().draw(context)
 
 		mat = context.material.mitsuba_material.mitsuba_mat_composite
 		weight = 0
+		missing = False
+		selfRef = False
+
 		for i in range(1,mat.nElements+1):
 			weight += getattr(mat, "mat%i_weight" % i)
+			name = getattr(mat, "mat%i_name" % i)
+			if name == '':
+				missing = True
+			elif name == context.material.name:
+				selfRef = True
 		if weight > 1:
 			row = self.layout.row()
-			row.label("Warning: material weights sum to >1")
+			row.label("Warning: material weights sum to >1!")
+		if selfRef:
+			row = self.layout.row()
+			row.label("Warning: self references not allowed!")
+		if missing:
+			row = self.layout.row()
+			row.label("Warning: missing material reference!")