modularize style and add propagating widgets

backend/nodes/io.py

@@ -446,7 +446,30 @@ class Coordinate:
 
     def process(self, x: float, y: float) -> tuple:
         return ((float(x), float(y)),)
+    
+    
+@register_node(display_name="Coordinate Pair")
+class CoordinatePair:
+    """Provide a pair of Coordinates, for drawing lines between markers, etc."""
 
+    @classmethod
+    def INPUT_TYPES(cls):
+        return {
+            "required": {
+                "a": ("COORD",),
+                "b": ("COORD",),
+            }
+        }
+    
+    RETURN_TYPES = ("COORDPAIR",)
+    RETURN_NAMES = ("coord pair",)
+    FUNCTION = "process"
+    CATEGORY = "io"
+    DESCRIPTION = "Output a pair of coordinates."
+
+    def process(self, a: tuple, b: tuple) -> tuple:
+        return ((a, b),)
+    
 
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