minor edit to use built-ins for Shader

src/simple_hsb_func/HSBField_polar.gdshader

@@ -1,7 +1,5 @@
 shader_type canvas_item;
 
-#define TWO_PI 6.28318530718
-
 uniform vec2 resolution = vec2(40,40);
 uniform vec2 u_resolution;
 uniform float u_time;
@@ -26,7 +24,7 @@ void fragment() {
 	float angle = pow(atan(toCenter.y, toCenter.x), 1.0);
 	float radius = length(toCenter)*2.0;
 	
-	float normHue = (angle/TWO_PI)+0.5;
+	float normHue = (angle/(PI*2.0))+0.5;
 	normHue = pow(normHue, 3.0);
 	
 	color = hsb2rgb(vec3(normHue,radius,1.0));

src/simple_hsb_func/HSBField_polar.tscn

@@ -19,5 +19,7 @@ grow_vertical = 2
 [node name="ColorRect" type="ColorRect" parent="."]
 material = SubResource("ShaderMaterial_s1hel")
 layout_mode = 0
-offset_right = 40.0
-offset_bottom = 40.0
+offset_left = 276.0
+offset_top = 50.0
+offset_right = 316.0
+offset_bottom = 90.0