Koch Fractal node added

addons/ShaderLib/Procedural/Shapes/KochFractal.gd

@@ -0,0 +1,86 @@
+@tool
+class_name VisualShaderNodeProceduralKochFractal extends VisualShaderNodeCustom
+
+func _init() -> void:
+	output_port_for_preview = 0
+
+func _get_name() -> String:
+	return "KochFractal"
+
+func _get_category() -> String:
+	return "Procedural/Shapes"
+
+func _get_description() -> String:
+	return "Generates an koch curve similar to ice fractal shape based on input UV at the size specified by inputs width and height."
+
+func _get_return_icon_type() -> PortType:
+	return PORT_TYPE_SCALAR
+
+func _get_input_port_count() -> int:
+	return 5
+
+func _get_input_port_name(port: int) -> String:
+	match port:
+		0:
+			return "uv"
+		1:
+			return "thickness"
+		2:
+			return "iterations"
+		3:
+			return "widht"
+		_:
+			return "height"
+
+func _get_input_port_type(port: int) -> PortType:
+	match port:
+		0:
+			return PORT_TYPE_VECTOR_2D
+		2:
+			return PORT_TYPE_SCALAR_INT
+		_:
+			return PORT_TYPE_SCALAR
+
+func _get_input_port_default_value(port: int) -> Variant:
+	match port:
+		1, 3, 4:
+			return 1.0
+		2:
+			return 3
+		_:
+			return null
+
+func _get_output_port_count() -> int:
+	return 2
+
+func _get_output_port_name(port: int) -> String:
+	match port:
+		0:
+			return "out"
+		_:
+			return "uv"
+
+func _get_output_port_type(port: int) -> PortType:
+	match port:
+		1:
+			return PORT_TYPE_VECTOR_2D
+		_:
+			return PORT_TYPE_SCALAR
+
+func _get_global_code(mode: Shader.Mode) -> String:
+	var code: String = preload("KochFractal.gdshaderinc").code
+	return code
+
+func _get_code(input_vars: Array[String], output_vars: Array[String], mode: Shader.Mode, type: VisualShader.Type) -> String:
+	var uv: String = "UV"
+
+	if input_vars[0]:
+		uv = input_vars[0]
+
+	var thickness: String = input_vars[1]
+	var iterations: String = input_vars[2]
+	var width: String = input_vars[3]
+	var height: String = input_vars[4]
+
+	return output_vars[0] + " = koch_fractal(%s, %s, %s, %s, %s, %s);" % [uv, thickness, iterations, width, height, output_vars[1]]
+

addons/ShaderLib/Procedural/Shapes/KochFractal.gdshaderinc

@@ -0,0 +1,36 @@
+vec2 koch_fractal_direction(float angle){
+	return vec2(sin(angle), cos(angle));
+}
+
+float koch_fractal(vec2 uv, float outline, int iteration, float shape_width, float shape_height, out vec2 koch_uv) {
+	float tiling = 3.0;
+	vec2 center = uv - vec2(.5);
+	shape_width =  .85 * (shape_width / 1.);
+	shape_height = .85 * (shape_height / 1.);
+	center.x /= shape_width;
+	center.y /= shape_height;
+
+	center.x = abs(center.x);
+	center.y += tan(.833 * PI) * .5;
+	vec2 dir = koch_fractal_direction(.833 * PI);
+	float dist = dot(center - vec2(tiling / (2. * tiling), 0), dir);
+	center -= dir * max(0, dist) * 2.0;
+
+	dir = koch_fractal_direction(.6667 * PI);
+	float scale = 1.0;
+	center.x += .5;
+	for(int i = 0; i < iteration; i++){
+		center *= tiling;
+		scale *= tiling;
+		center.x -= .5 * tiling;
+
+		center.x = abs(center.x);
+		center.x -= .5;
+		center -= dir * min(0.0, dot(center, dir)) * 2.0;
+	}
+
+	dist = length(center - vec2(clamp(center.x, -1.0, 1.0), 0));
+	dist += step(outline / 100.0, dist / scale);
+	koch_uv = center;
+	return 1.0 - dist;
+}