diff --git a/addons/material_maker/engine/gen_iterate_buffer.gd b/addons/material_maker/engine/gen_iterate_buffer.gd
index 05d10ebc..3d6bce2b 100644
--- a/addons/material_maker/engine/gen_iterate_buffer.gd
+++ b/addons/material_maker/engine/gen_iterate_buffer.gd
@@ -53,11 +53,11 @@ func get_output_defs() -> Array:
 	return [ { type="rgba" }, { type="rgba" } ]
 
 func source_changed(input_port_index : int) -> void:
-	current_iteration = 0
+	set_current_iteration(0)
 	call_deferred("update_shader", input_port_index)
 
 func all_sources_changed() -> void:
-	current_iteration = 0
+	set_current_iteration(0)
 	call_deferred("update_shader", 0)
 	call_deferred("update_shader", 1)
 
@@ -98,7 +98,7 @@ func set_pending() -> void:
 
 func set_parameter(n : String, v) -> void:
 	.set_parameter(n, v)
-	current_iteration = 0
+	set_current_iteration(0)
 	if is_inside_tree():
 		update_buffer()
 
@@ -106,11 +106,12 @@ func on_float_parameters_changed(parameter_changes : Dictionary) -> void:
 	var do_update : bool = false
 	if parameter_changes.has("p_o%s_iterations" % str(get_instance_id())):
 		do_update = true
+	var not_just_iteration = parameter_changes.size() > 1 or not parameter_changes.has("o%s_iteration" % str(get_instance_id()))
 	for i in range(2):
 		var m : Material = [ material, loop_material ][i]
-		if mm_renderer.update_float_parameters(m, parameter_changes):
+		if mm_renderer.update_float_parameters(m, parameter_changes) and not_just_iteration:
 			update_again = true
-			current_iteration = 0
+			set_current_iteration(0)
 			if pending_textures[i].empty():
 				update_buffer()
 
@@ -122,7 +123,7 @@ func on_texture_changed(n : String) -> void:
 			for p in VisualServer.shader_get_param_list(m.shader.get_rid()):
 				if p.name == n:
 					if i == 0:
-						current_iteration = 0
+						set_current_iteration(0)
 					update_buffer()
 					return
 
@@ -137,6 +138,13 @@ func on_texture_invalidated(n : String) -> void:
 			if pending_textures[i].find(n) == -1:
 				pending_textures[i].push_back(n)
 
+func set_current_iteration(i : int) -> void:
+	current_iteration = i
+	var iteration_param_name = "o%s_iteration" % str(get_instance_id())
+	if is_inside_tree():
+		get_tree().call_group("preview", "on_float_parameters_changed", { iteration_param_name:current_iteration })
+
+
 func update_buffer() -> void:
 	update_again = true
 	if !updating:
@@ -164,14 +172,14 @@ func update_buffer() -> void:
 			renderer.release(self)
 			current_renderer = null
 		updating = false
-		if current_iteration < get_parameter("iterations"):
+		set_current_iteration(current_iteration+1)
+		if current_iteration <= get_parameter("iterations"):
 			get_tree().call_group("preview", "on_texture_changed", "o%s_loop_tex" % str(get_instance_id()))
 		else:
 			get_tree().call_group("preview", "on_texture_changed", "o%s_tex" % str(get_instance_id()))
-		current_iteration += 1
 
 func get_globals(texture_name : String) -> Array:
-	var texture_globals : String = "uniform sampler2D %s;\nuniform float %s_size = %d.0;\n" % [ texture_name, texture_name, pow(2, get_parameter("size")) ]
+	var texture_globals : String = "uniform sampler2D %s;\nuniform float %s_size = %d.0;\nuniform float o%s_iteration = 0.0;\n" % [ texture_name, texture_name, pow(2, get_parameter("size")), str(get_instance_id()) ]
 	return [ texture_globals ]
 
 func _get_shader_code(uv : String, output_index : int, context : MMGenContext) -> Dictionary:
diff --git a/addons/material_maker/engine/gen_shader.gd b/addons/material_maker/engine/gen_shader.gd
index c0a4f692..796cb9c5 100644
--- a/addons/material_maker/engine/gen_shader.gd
+++ b/addons/material_maker/engine/gen_shader.gd
@@ -274,10 +274,11 @@ func subst(string : String, context : MMGenContext, uv : String = "") -> Diction
 			if source == null:
 				continue
 			var src_attributes = source.generator.get_output_attributes(source.output_index)
-			if src_attributes.has("texture"):
-				variables[input.name+".texture"] = src_attributes.texture
-			if src_attributes.has("texture_size"):
-				variables[input.name+".size"] = src_attributes.texture_size
+			for a in src_attributes.keys():
+				if a == "texture_size":
+					variables[input.name+".size"] = src_attributes.texture_size
+				else:
+					variables[input.name+"."+a] = src_attributes[a]
 	string = replace_variables(string, variables)
 	if shader_model.has("inputs") and typeof(shader_model.inputs) == TYPE_ARRAY:
 		var cont = true