More refactoring on rtexture generation

addons/material_maker/engine/gen_base.gd

@@ -9,7 +9,7 @@ class OutputPort:
 	func _init(g : MMGenBase, o : int):
 		generator = g
 		output_index = o
-	
+	"""
 	func get_shader():
 		return generator.get_shader(output_index)
 	
@@ -18,19 +18,43 @@ class OutputPort:
 	
 	func get_globals():
 		return generator.get_globals()
-	
+	"""
 	func to_str():
 		return generator.name+"("+str(output_index)+")"
 
 var position : Vector2 = Vector2(0, 0)
 var parameters = {}
 
+func _ready():
+	init_parameters()
+
+func init_parameters():
+	for p in get_parameter_defs():
+		print(p)
+		if !parameters.has(p.name):
+			if p.has("default"):
+				parameters[p.name] = MMType.deserialize_value(p.default)
+			else:
+				print("No default value for parameter "+p.name)
+
 func get_seed():
 	return 0
 
 func get_type():
 	return "generic"
 
+func get_type_name():
+	return "Unnamed"
+
+func get_parameter_defs():
+	return []
+
+func get_input_defs():
+	return []
+
+func get_output_defs():
+	return []
+
 func get_source(input_index : int):
 	return get_parent().get_port_source(name, input_index)
 
@@ -39,7 +63,7 @@ func get_input_shader(input_index : int):
 	if source != null:
 		return source.get_shader()
 
-func get_shader(output_index : int, context = MMGenContext.new()):
+func get_shader(output_index : int, context):
 	return get_shader_code("UV", output_index, context);
 
 # this will need an output index for switch
@@ -48,14 +72,25 @@ func get_globals():
 	for i in range(10):
 		var source = get_source(i)
 		if source != null:
-			var source_list = source.get_globals()
+			var source_list = source.generator.get_globals()
 			for g in source_list:
 				if list.find(g) == -1:
 					list.append(g)
 	return list
 
-func get_shader_code(uv, slot = 0, context = MMGenContext.new()):
+func render(output_index : int, renderer : MMGenRenderer, size : int):
-	var rv = _get_shader_code(uv, slot, context)
+	var context : MMGenContext = MMGenContext.new(renderer)
+	var source = get_shader_code("UV", output_index, context)
+	if source == null:
+		return false
+	var shader : String = renderer.generate_shader(source)
+	var status = renderer.render_shader(shader, {}, 1024)
+	while status is GDScriptFunctionState:
+		status = yield(status, "completed")
+	return status
+
+func get_shader_code(uv : String, output_index : int, context : MMGenContext):
+	var rv = _get_shader_code(uv, output_index, context)
 	if rv != null:
 		if !rv.has("f"):
 			if rv.has("rgb"):
@@ -74,5 +109,5 @@ func get_shader_code(uv, slot = 0, context = MMGenContext.new()):
 		rv.globals = get_globals()
 	return rv
 
-func _get_shader_code(uv : String, output_index : int, context = MMGenContext.new()):
+func _get_shader_code(uv : String, output_index : int, context : MMGenContext):
 	return null

addons/material_maker/engine/gen_buffer.gd

@@ -1,2 +1,22 @@
+tool
 extends MMGenBase
 class_name MMGenBuffer
+
+func _ready():
+	if !parameters.has("size"):
+		parameters.size = 4
+
+func get_type():
+	return "buffer"
+
+func get_type_name():
+	return "Buffer"
+
+func get_parameter_defs():
+	return [ { name="size", type="size", first=4, last=11, default=4 } ]
+
+func get_input_defs():
+	return [ ]
+
+func get_output_defs():
+	return [ ]

addons/material_maker/engine/gen_context.gd

@@ -1,8 +1,13 @@
+tool
 extends Object
 class_name MMGenContext
 
+var renderer : MMGenRenderer
 var variants : Dictionary = {}
 
+func _init(r : MMGenRenderer):
+	renderer = r
+
 func has_variant(generator):
 	return variants.has(generator)
 

addons/material_maker/engine/gen_convolution.gd

@@ -1,2 +1,3 @@
+tool
 extends MMGenBase
 class_name MMGenConvolution

addons/material_maker/engine/gen_graph.gd

@@ -4,9 +4,14 @@ class_name MMGenGraph
 
 var connections = []
 
+func get_type():
+	return "graph"
+
 func get_port_source(gen_name: String, input_index: int) -> OutputPort:
 	for c in connections:
 		if c.to == gen_name and c.to_port == input_index:
+			var src_gen = get_node(c.from)
+			if src_gen != null:
 				return OutputPort.new(get_node(c.from), c.from_port)
 	return null
 

addons/material_maker/engine/gen_material.gd

@@ -43,6 +43,7 @@ func generate_material(renderer : MMGenRenderer):
 		var status = renderer.render_shader(shader, {}, 512)
 		while status is GDScriptFunctionState:
 			status = yield(status, "completed")
+		print("Render status: "+str(status))
 		renderer.get_texture().get_data().save_png("res://test.png")
 		material.albedo_texture = load("res://test.png")
 	return material

addons/material_maker/engine/gen_shader.gd

@@ -2,21 +2,26 @@ tool
 extends MMGenBase
 class_name MMGenShader
 
-var model_data = null
+var shader_model : Dictionary = {}
 var generated_variants = []
 
-func set_model_data(data: Dictionary):
+func get_type():
-	model_data = data
+	return "shader"
-	for p in model_data.parameters:
-		if !parameters.has(p.name) and  p.has("default"):
-			parameters[p.name] = MMType.deserialize_value(p.default)
 
-func initialize(data: Dictionary):
+func get_type_name():
-	if data.has("name"):
+	if shader_model.has("name"): 
-		name = data.name
+		return shader_model.name
-	if data.has("parameters"):
+	return .get_type_name()
-		for p in data.parameters.keys():
+
-			parameters[p] = data.parameters[p]
+func get_parameter_defs():
+	if shader_model == null or !shader_model.has("parameters"):
+		return []
+	else:
+		return shader_model.parameters
+
+func set_shader_model(data: Dictionary):
+	shader_model = data
+	init_parameters()
 
 func find_keyword_call(string, keyword):
 	var search_string = "$%s(" % keyword
@@ -49,7 +54,8 @@ func replace_input(string, context, input, type, src, default):
 		if src == null:
 			src_code = subst(default, "(%s)" % uv)
 		else:
-			src_code = src.get_shader_code(uv)
+			print(src.to_str())
+			src_code = src.generator.get_shader_code(uv, src.output_index, context)
 			src_code.string = src_code[type]
 		required_defs += src_code.defs
 		required_code += src_code.code
@@ -84,8 +90,8 @@ func subst(string, context, uv = ""):
 	string = replace_variable(string, "seed", str(get_seed()))
 	if uv != "":
 		string = replace_variable(string, "uv", "("+uv+")")
-	if model_data.has("parameters") and typeof(model_data.parameters) == TYPE_ARRAY:
+	if shader_model.has("parameters") and typeof(shader_model.parameters) == TYPE_ARRAY:
-		for p in model_data.parameters:
+		for p in shader_model.parameters:
 			if !p.has("name") or !p.has("type"):
 				continue
 			var value = parameters[p.name]
@@ -102,9 +108,9 @@ func subst(string, context, uv = ""):
 				value_string = p.name+"_gradient_fct"
 			if value_string != null:
 				string = replace_variable(string, p.name, value_string)
-	if model_data.has("inputs") and typeof(model_data.inputs) == TYPE_ARRAY:
+	if shader_model.has("inputs") and typeof(shader_model.inputs) == TYPE_ARRAY:
-		for i in range(model_data.inputs.size()):
+		for i in range(shader_model.inputs.size()):
-			var input = model_data.inputs[i]
+			var input = shader_model.inputs[i]
 			var source = get_source(i)
 			var result = replace_input(string, context, input.name, input.type, source, input.default)
 			string = result.string
@@ -112,18 +118,16 @@ func subst(string, context, uv = ""):
 			required_code += result.code
 	return { string=string, defs=required_defs, code=required_code }
 
-func _get_shader_code(uv, slot = 0, context = MMGenContext.new()):
+func _get_shader_code(uv : String, output_index : int, context : MMGenContext):
-	if context == null:
-		context = {}
 	var output_info = [ { field="rgba", type="vec4" }, { field="rgb", type="vec3" }, { field="f", type="float" } ]
 	var rv = { defs="", code="" }
-	var variant_string = uv+","+str(slot)
+	var variant_string = uv+","+str(output_index)
-	if model_data != null and model_data.has("outputs") and model_data.outputs.size() > slot:
+	if shader_model != null and shader_model.has("outputs") and shader_model.outputs.size() > output_index:
-		var output = model_data.outputs[slot]
+		var output = shader_model.outputs[output_index]
 		rv.defs = ""
-		if model_data.has("instance") && !context.has_variant(self):
+		if shader_model.has("instance") && !context.has_variant(self):
-			rv.defs += subst(model_data.instance, context).string
+			rv.defs += subst(shader_model.instance, context).string
-		for p in model_data.parameters:
+		for p in shader_model.parameters:
 			if p.type == "gradient":
 				var g = parameters[p.name]
 				if !(g is MMGradient):
@@ -139,14 +143,14 @@ func _get_shader_code(uv, slot = 0, context = MMGenContext.new()):
 					var subst_output = subst(output[t.field], context, uv)
 					rv.defs += subst_output.defs
 					rv.code += subst_output.code
-					rv.code += "%s %s_%d_%d_%s = %s;\n" % [ t.type, name, slot, variant_index, t.field, subst_output.string ]
+					rv.code += "%s %s_%d_%d_%s = %s;\n" % [ t.type, name, output_index, variant_index, t.field, subst_output.string ]
 		for t in output_info:
 			if output.has(t.field):
-				rv[t.field] = "%s_%d_%d_%s" % [ name, slot, variant_index, t.field ]
+				rv[t.field] = "%s_%d_%d_%s" % [ name, output_index, variant_index, t.field ]
 	return rv
 
 func get_globals():
 	var list = .get_globals()
-	if typeof(model_data) == TYPE_DICTIONARY and model_data.has("global") and list.find(model_data.global) == -1:
+	if typeof(shader_model) == TYPE_DICTIONARY and shader_model.has("global") and list.find(shader_model.global) == -1:
-		list.append(model_data.global)
+		list.append(shader_model.global)
 	return list

addons/material_maker/engine/loader.gd

@@ -32,27 +32,28 @@ func create_gen(data) -> MMGenBase:
 	if data.has("connections") and data.has("nodes"):
 		generator = MMGenGraph.new()
 		add_to_gen_graph(generator, data.nodes, data.connections)
-	elif data.has("model_data"):
+	elif data.has("shader_model"):
 		generator = MMGenShader.new()
-		generator.set_model_data(data.model_data)
+		generator.set_shader_model(data.shader_model)
 	elif data.has("type"):
 		if data.type == "material":
 			generator = MMGenMaterial.new()
+		elif data.type == "buffer":
+			generator = MMGenBuffer.new()
 		else:
 			var file = File.new()
 			if file.open("res://addons/material_maker/library/"+data.type+".mml", File.READ) == OK:
-				var model_data = parse_json(file.get_as_text())
 				print("loaded description "+data.type+".mml")
-				generator = create_gen(model_data)
+				generator = create_gen(parse_json(file.get_as_text()))
 				file.close()
 			elif file.open("res://addons/material_maker/nodes/"+data.type+".mmn", File.READ) == OK:
 				generator = MMGenShader.new()
-				var model_data = parse_json(file.get_as_text())
 				print("loaded description "+data.type+".mmn")
-				generator.set_model_data(model_data)
+				generator.set_shader_model(parse_json(file.get_as_text()))
 				file.close()
 			else:
 				print("Cannot find description for "+data.type)
+		if generator != null:
 			generator.name = data.type
 	else:
 		print(data)
@@ -63,5 +64,6 @@ func create_gen(data) -> MMGenBase:
 			generator.position.x = data.node_position.x
 			generator.position.y = data.node_position.y
 		if data.has("parameters"):
-			generator.initialize(data)
+			for p in data.parameters.keys():
+				generator.parameters[p] = data.parameters[p]
 	return generator

addons/material_maker/engine/renderer.gd

@@ -68,6 +68,7 @@ func setup_material(shader_material, textures, shader_code):
 
 func render_shader(shader, textures, render_size):
 	if rendering:
+		print("Already rendering...")
 		return false
 	rendering = true
 	if debug_path != null and debug_path != "":

addons/material_maker/graph_edit.gd

@@ -128,7 +128,7 @@ func get_free_name(type):
 			return node_name
 		i += 1
 
-func create_nodes(data, position = null):
+func create_nodes(data, position : Vector2 = Vector2(0, 0)):
 	if data == null:
 		return
 	if data.has("type"):
@@ -136,6 +136,8 @@ func create_nodes(data, position = null):
 	if typeof(data.nodes) == TYPE_ARRAY and typeof(data.connections) == TYPE_ARRAY:
 		var loader = MMGenLoader.new()
 		var new_stuff = loader.add_to_gen_graph(generator, data.nodes, data.connections)
+		for g in new_stuff.generators:
+			g.position += position
 		update_graph(new_stuff.generators, new_stuff.connections)
 
 func load_file(filename):

addons/material_maker/library/base.json

@@ -28,46 +28,55 @@
 		"tree_item":"Generators/Pattern",
 		"icon":"pattern",
 		"type":"pattern",
+		"parameters":{
 			"mix":0,
 			"x_scale":4,
 			"x_wave":0,
 			"y_scale":4,
 			"y_wave":0
+		}
 	},
     {
 		"tree_item": "Generators/Pattern/Checkerboard",
 		"type": "pattern",
 		"icon": "checkerboard",
+		"parameters":{
 			"mix": 4,
 			"x_scale": 4,
 			"x_wave": 2,
 			"y_scale": 4,
 			"y_wave": 2
+		}
     },
 	{
 		"tree_item":"Generators/Bricks",
 		"type":"bricks",
 		"icon":"bricks",
+		"parameters":{
 			"bevel":0.1,
 			"columns":3,
 			"mortar":0.1,
 			"row_offset":0.5,
 			"rows":6
+		}
 	},
     {
 		"tree_item": "Generators/Bricks/Tiles",
 		"type": "bricks",
 		"icon": "tiles",
+		"parameters":{
 			"bevel": 0.05,
 			"columns": 4,
 			"mortar": 0.05,
 			"row_offset": 0,
 			"rows": 4
+		}
 	},
     {
 		"tree_item": "Generators/Bricks/BasketWeave",
 		"type": "bricks",
 		"icon": "basketweave",
+		"parameters":{
 			"bevel": 0.05,
 			"columns": 2,
 			"mortar": 0.05,
@@ -75,11 +84,13 @@
 			"repeat": 2,
 			"row_offset": 0,
 			"rows": 2
+		}
     },
     {
 		"tree_item": "Generators/Bricks/HerringBone",
 		"type": "bricks",
 		"icon": "herringbone",
+		"parameters":{
 			"bevel": 0.05,
 			"columns": 2,
 			"mortar": 0.05,
@@ -87,11 +98,13 @@
 			"repeat": 2,
 			"row_offset": 0,
 			"rows": 2
+		}
     },
     {
 		"tree_item": "Generators/Bricks/SpanishBond",
 		"type": "bricks",
 		"icon": "spanishbond",
+		"parameters":{
 			"bevel": 0.05,
 			"columns": 2,
 			"mortar": 0.05,
@@ -99,53 +112,72 @@
 			"repeat": 2,
 			"row_offset": 0,
 			"rows": 2
+		}
     },
 	{
 		"tree_item":"Generators/Noise",
 		"type":"noise",
 		"icon":"noise",
+		"parameters":{
 			"size":4,
 			"density":0.5
+		}
 	},
 	{
 		"tree_item":"Generators/Perlin Noise",
 		"type":"perlin",
 		"icon":"perlin",
+		"parameters":{
 			"iterations":3,
 			"persistence":0.5,
 			"scale_x":4,
 			"scale_y":4
+		}
 	},
 	{
 		"tree_item":"Generators/Voronoi Noise",
 		"type":"voronoi",
 		"icon":"voronoi",
+		"parameters":{
 			"intensity":1,
 			"scale_x":4,
 			"scale_y":4
+		}
+	},
+	{
+		"tree_item":"Filters/Buffer",
+		"type":"buffer"
 	},
 	{
 		"tree_item":"Filters/AdjustHSV",
 		"type":"adjust_hsv",
+		"parameters":{
 			"hue":0,
 			"saturation":1,
 			"value":1
+		}
 	},
 	{
 		"tree_item":"Filters/Colorize",
 		"type":"colorize",
+		"parameters":{
 			"gradient":[{"b":0,"g":0,"pos":0,"r":0},{"b":1,"g":1,"pos":1,"r":1}]
+		}
 	},
 	{
 		"tree_item":"Filters/Blend",
 		"type":"blend",
+		"parameters":{
 			"amount":0.5,
 			"blend_type":0
+		}
 	},
 	{
 		"tree_item":"Filters/Blur",
 		"type":"blur",
+		"parameters":{
 			"sigma":1.0
+		}
 	},
 	{
 		"tree_item":"Filters/Combine",
@@ -158,31 +190,40 @@
 	{
 		"tree_item":"Filters/Emboss",
 		"type":"emboss",
+		"parameters":{
 			"direction":0
+		}
 	},
 	{
 		"tree_item":"Filters/Normal map",
 		"type":"normal_map",
+		"parameters":{
 			"amount":0.5
+		}
 	},
 	{
 		"tree_item":"Filters/Transform",
 		"type":"transform",
+		"parameters":{
 			"rotate":0,
 			"scale_x":1,
 			"scale_y":1,
 			"translate_x":0,
 			"translate_y":0
+		}
 	},
 	{
 		"tree_item":"Filters/Warp",
 		"type":"warp",
+		"parameters":{
 			"amount":0.5
+		}
 	},
     {
 		"tree_item": "Filters/Colorize/Invert",
 		"type": "colorize",
 		"icon": "invert",
+		"parameters":{
 			"gradient": [
 				{
 					"b": 1,
@@ -197,6 +238,7 @@
 					"r": 0
 				}
 			]	
+		}
 	},
 	{
 		"tree_item":"Miscellaneous/Comment",

addons/material_maker/main_window.gd

@@ -311,12 +311,10 @@ func update_preview_2d(node = null):
 				node = n
 				break
 	if node != null:
-		var source = node.generator.get_shader(0)
+		var status = node.generator.render(0, renderer, 1024)
-		if source != null:
-			var shader : String = renderer.generate_shader(source)
-			var status = renderer.render_shader(shader, {}, 1024)
 		while status is GDScriptFunctionState:
 			status = yield(status, "completed")
+		if status:
 			var image = renderer.get_texture().get_data()
 			var tex = ImageTexture.new()
 			tex.create_from_image(image)

addons/material_maker/node_factory.gd

@@ -15,4 +15,6 @@ func create_node(type):
 		var node_type = load("res://addons/material_maker/nodes/"+type+".tscn")
 		if node_type != null:
 			node = node_type.instance()
+		else:
+			node = preload("res://addons/material_maker/nodes/generic.tscn").instance()
 	return node

addons/material_maker/nodes/bricks.mmn

@@ -1,7 +1,7 @@
 {
 	"name":"Bricks",
 	"parameters":[
-		{ "name":"pattern", "label":"", "type":"enum", "values":[
+		{ "name":"pattern", "label":"", "type":"enum", "default":0, "values":[
 			{ "name":"Running bond",     "value":"rb" },
 			{ "name":"Running bond (2)", "value":"rb2" },
 			{ "name":"HerringBone",      "value":"hb" },

addons/material_maker/nodes/generic.gd

@@ -6,16 +6,16 @@ var controls = []
 
 var uses_seed : bool = false
 
-var parameters = {}
-var model_data = {}
-
 # Called when the node enters the scene tree for the first time.
 func _ready():
 	pass # Replace with function body.
 
 func set_generator(g):
 	generator = g
-	update_node(g.model_data)
+	if g.get("shader_model") != null:
+		update_node(g.shader_model)
+	else:
+		update_node({})
 
 func initialize_properties():
 	for o in controls:
@@ -70,13 +70,9 @@ func _on_gradient_changed(new_gradient, variable):
 	update_shaders()
 
 func update_node(data):
-	print("node_generic.update_node")
 	if typeof(data) != TYPE_DICTIONARY:
 		return
-	if !data.has("name"):
-		return
 	# Clean node
-	parameters = {}
 	var custom_node_buttons = null
 	for c in get_children():
 		if c.name != "CustomNodeButtons":
@@ -85,17 +81,18 @@ func update_node(data):
 		else:
 			custom_node_buttons = c
 	# Rebuild node
-	title = data.name
+	title = generator.get_type_name()
-	model_data = data
 	uses_seed = false
-	if model_data.has("instance") and model_data.instance.find("$(seed)"):
+	if data.has("instance") and data.instance.find("$(seed)"):
 		uses_seed = true
-	if model_data.has("parameters") and typeof(model_data.parameters) == TYPE_ARRAY:
+	# Parameters
+	print("Parameters")
 	controls = []
 	var sizer = null
-		for p in model_data.parameters:
+	for p in generator.get_parameter_defs():
 		if !p.has("name") or !p.has("type"):
 			continue
+		print(p.name)
 		var control = null
 		if p.type == "float":
 			if p.has("widget") and p.widget == "spinbox":
@@ -108,7 +105,6 @@ func update_node(data):
 			if p.has("default"):
 				control.value = p.default
 			control.rect_min_size.x = 80
-				parameters[p.name] = 0.5*(p.min+p.max)
 		elif p.type == "size":
 			control = OptionButton.new()
 			for i in range(p.first, p.last+1):
@@ -145,11 +141,9 @@ func update_node(data):
 			control.size_flags_horizontal = SIZE_EXPAND | SIZE_FILL
 			sizer.add_child(control)
 	initialize_properties()
-	else:
+	if data.has("inputs") and typeof(data.inputs) == TYPE_ARRAY:
-		model_data.parameters = []
+		for i in range(data.inputs.size()):
-	if model_data.has("inputs") and typeof(model_data.inputs) == TYPE_ARRAY:
+			var input = data.inputs[i]
-		for i in range(model_data.inputs.size()):
-			var input = model_data.inputs[i]
 			var enable_left = false
 			var color_left = Color(0.5, 0.5, 0.5)
 			if typeof(input) == TYPE_DICTIONARY:
@@ -162,11 +156,9 @@ func update_node(data):
 				else:
 					enable_left = true
 			set_slot(i, enable_left, 0, color_left, false, 0, Color())
-	else:
+	if data.has("outputs") and typeof(data.outputs) == TYPE_ARRAY:
-		model_data.inputs = []
+		for i in range(data.outputs.size()):
-	if model_data.has("outputs") and typeof(model_data.outputs) == TYPE_ARRAY:
+			var output = data.outputs[i]
-		for i in range(model_data.outputs.size()):
-			var output = model_data.outputs[i]
 			var enable_right = false
 			var color_right = Color(0.5, 0.5, 0.5)
 			if typeof(output) == TYPE_DICTIONARY:
@@ -179,7 +171,5 @@ func update_node(data):
 				elif output.has("f"):
 					enable_right = true
 			set_slot(i, is_slot_enabled_left(i), get_slot_type_left(i), get_slot_color_left(i), enable_right, 0, color_right)
-	else:
-		model_data.outputs = []
 	if custom_node_buttons != null:
 		move_child(custom_node_buttons, get_child_count()-1)

addons/material_maker/plugin.gd

@@ -51,4 +51,7 @@ func generate_material(ptex_filename: String) -> Material:
 	var generator = loader.load_gen(ptex_filename)
 	add_child(generator)
 	var material = generator.get_node("Material")
-	return material.generate_material(renderer)
+	var return_value = material.generate_material(renderer)
+	while return_value is GDScriptFunctionState:
+		return_value = yield(return_value, "completed")
+	return return_value

addons/material_maker/types/gradient.gd

@@ -8,9 +8,6 @@ class CustomSorter:
 var points = [ { v=0.0, c=Color(0.0, 0.0, 0.0, 0.0) }, { v=1.0, c=Color(1.0, 1.0, 1.0, 1.0) } ]
 var sorted = true
 
-func _ready():
-	pass
-
 func to_string():
 	var rv = PoolStringArray()
 	for p in points:
@@ -39,6 +36,7 @@ func sort():
 
 func get_color(x):
 	sort()
+	if points.size() >0:
 		if x < points[0].v:
 			return points[0].c
 		var s = points.size()-1
@@ -50,6 +48,8 @@ func get_color(x):
 				var c1 = points[i+1].c
 				return c0 + (c1-c0) * (x-p0) / (p1-p0)
 		return points[s].c
+	else:
+		return Color(0.0, 0.0, 0.0, 1.0)
 
 # get_color_in_shader
 func gcis(color):
@@ -59,6 +59,7 @@ func get_shader(name):
 	sort()
 	var shader
 	shader  = "vec4 "+name+"(float x) {\n"
+	if points.size() > 0:
 		shader += "  if (x < %.9f) {\n" % points[0].v
 		shader += "    return "+gcis(points[0].c)+";\n"
 		var s = points.size()-1
@@ -72,6 +73,8 @@ func get_shader(name):
 				shader += "    return %s+x*%s;\n" % [gcis(c0-c1mc0*(p0/p1mp0)), gcis(c1mc0/p1mp0)]
 		shader += "  }\n"
 		shader += "  return "+gcis(points[s].c)+";\n"
+	else:
+		shader += "  return vec4(0.0, 0.0, 0.0, 1.0);\n"
 	shader += "}\n"
 	return shader
 
@@ -89,7 +92,7 @@ func deserialize(v):
 		for i in v:
 			if !i.has("a"): i.a = 1.0
 			add_point(i.pos, Color(i.r, i.g, i.b, i.a))
-	elif typeof(v) == TYPE_DICTIONARY && v.has("type") && v.type == "Gradient":
+	elif typeof(v) == TYPE_DICTIONARY and v.has("type") && v.type == "Gradient":
 		for i in v.points:
 			if !i.has("a"): i.a = 1.0
 			add_point(i.pos, Color(i.r, i.g, i.b, i.a))

test.ptex

@@ -1 +1,158 @@
-{"connections":[{"from":"bricks_0","from_port":0,"to":"custom_0","to_port":0},{"from":"custom_0","from_port":0,"to":"adjust_hsv_0","to_port":0},{"from":"adjust_hsv_0","from_port":0,"to":"Material","to_port":0}],"nodes":[{"name":"Material","node_position":{"x":143,"y":-210},"parameters":{"albedo_color":{"a":1,"b":1,"g":1,"r":1,"type":"Color"},"ao_light_affect":1,"depth_scale":1,"emission_energy":1,"metallic":1,"normal_scale":1,"resolution":1,"roughness":1},"type":"material"},{"model_data":{"global":"","inputs":[{"default":"0.0","label":"Input","name":"input","type":"f"}],"instance":"","name":"Colorize","outputs":[{"rgba":"$gradient($input($uv))"}],"parameters":[{"default":{"points":[{"a":1,"b":0,"g":0,"pos":0,"r":0},{"a":1,"b":1,"g":1,"pos":1,"r":1}],"type":"Gradient"},"label":"Gradient","name":"gradient","type":"gradient"}]},"name":"custom_0","node_position":{"x":-433,"y":-109.416656},"parameters":{"gradient":{"points":[{"a":1,"b":0,"g":0,"pos":0,"r":0},{"a":1,"b":0,"g":0,"pos":0.517045,"r":1},{"a":0,"b":1,"g":1,"pos":1,"r":1}],"type":"Gradient"}},"type":"custom"},{"name":"adjust_hsv_0","node_position":{"x":-135.541687,"y":-150.597229},"parameters":{"hue":0,"saturation":1,"value":1},"type":"adjust_hsv"},{"name":"bricks_0","node_position":{"x":-599,"y":-332},"parameters":{"bevel":0.209961,"columns":3,"mortar":0.116211,"pattern":0,"repeat":1,"row_offset":0.5,"rows":6},"type":"bricks"}]}
+{
+  "connections": [
+    {
+      "from": "bricks_0",
+      "from_port": 0,
+      "to": "custom_0",
+      "to_port": 0
+    },
+    {
+      "from": "custom_0",
+      "from_port": 0,
+      "to": "adjust_hsv_0",
+      "to_port": 0
+    },
+    {
+      "from": "adjust_hsv_0",
+      "from_port": 0,
+      "to": "Material",
+      "to_port": 0
+    }
+  ],
+  "nodes": [
+    {
+      "name": "Material",
+      "node_position": {
+        "x": 143,
+        "y": -210
+      },
+      "parameters": {
+        "albedo_color": {
+          "a": 1,
+          "b": 1,
+          "g": 1,
+          "r": 1,
+          "type": "Color"
+        },
+        "ao_light_affect": 1,
+        "depth_scale": 1,
+        "emission_energy": 1,
+        "metallic": 1,
+        "normal_scale": 1,
+        "resolution": 1,
+        "roughness": 1
+      },
+      "type": "material"
+    },
+    {
+      "shader_model": {
+        "global": "",
+        "inputs": [
+          {
+            "default": "0.0",
+            "label": "Input",
+            "name": "input",
+            "type": "f"
+          }
+        ],
+        "instance": "",
+        "name": "Colorize",
+        "outputs": [
+          {
+            "rgba": "$gradient($input($uv))"
+          }
+        ],
+        "parameters": [
+          {
+            "default": {
+              "points": [
+                {
+                  "a": 1,
+                  "b": 0,
+                  "g": 0,
+                  "pos": 0,
+                  "r": 0
+                },
+                {
+                  "a": 1,
+                  "b": 1,
+                  "g": 1,
+                  "pos": 1,
+                  "r": 1
+                }
+              ],
+              "type": "Gradient"
+            },
+            "label": "Gradient",
+            "name": "gradient",
+            "type": "gradient"
+          }
+        ]
+      },
+      "name": "custom_0",
+      "node_position": {
+        "x": -433,
+        "y": -109.416656
+      },
+      "parameters": {
+        "gradient": {
+          "points": [
+            {
+              "a": 1,
+              "b": 0,
+              "g": 0,
+              "pos": 0,
+              "r": 0
+            },
+            {
+              "a": 1,
+              "b": 0,
+              "g": 0,
+              "pos": 0.517045,
+              "r": 1
+            },
+            {
+              "a": 0,
+              "b": 1,
+              "g": 1,
+              "pos": 1,
+              "r": 1
+            }
+          ],
+          "type": "Gradient"
+        }
+      },
+      "type": "custom"
+    },
+    {
+      "name": "adjust_hsv_0",
+      "node_position": {
+        "x": -135.541687,
+        "y": -150.597229
+      },
+      "parameters": {
+        "hue": 0,
+        "saturation": 1,
+        "value": 1
+      },
+      "type": "adjust_hsv"
+    },
+    {
+      "name": "bricks_0",
+      "node_position": {
+        "x": -599,
+        "y": -332
+      },
+      "parameters": {
+        "bevel": 0.209961,
+        "columns": 3,
+        "mortar": 0.116211,
+        "pattern": 0,
+        "repeat": 1,
+        "row_offset": 0.5,
+        "rows": 6
+      },
+      "type": "bricks"
+    }
+  ]
+}