Make some minor adjustments to graph arrow rendering

documents/references.md

@@ -27,6 +27,7 @@ for this project), it's being set up as a submodule project for now.
 This ended up being more complicated than I expected.
 * Main Ref was: <https://stackoverflow.com/a/51370419>
 * Secondary Ref: <https://math.stackexchange.com/questions/428843/draw-directional-arrows-on-a-given-line>
+* Finding Midpoint: <https://math.stackexchange.com/questions/563566/how-do-i-find-the-middle1-2-1-3-1-4-etc-of-a-line>
 
 ### Trig "Cheat Sheet" to Help Determine Self-connecting Loop Coordinates
 * <http://tutorial.math.lamar.edu/pdf/trig_cheat_sheet.pdf>

resources/graphs/directed_graph/graph.py

@@ -87,9 +87,9 @@ class DirectedGraph(BasicGraph):
             else:
                 # Node is linking to another node.
 
-                # Calculate midpoint.
-                mid_x = (tail_x + head_x) / 2
-                mid_y = (tail_y + head_y) / 2
+                # Calculate "midpoint". In our case, we want it slightly offset from center, closer to head node.
+                mid_x = ( 1/4 * tail_x ) + ( 3/4 * head_x )
+                mid_y = ( 1/4 * tail_y ) + ( 3/4 * head_y )
 
                 # Get arrow "length" and "distance" values.
                 length, distance = self._calc_distance_and_length(head_x, head_y, tail_x, tail_y)
@@ -157,27 +157,32 @@ class DirectedGraph(BasicGraph):
         really large directional arrows. For reasons I don't understand, using the math below made it a lot more
         consistent and uniform.
         """
-        # Get initial values, proportionally based off of cords of nodes.
-        length = math.sqrt(abs((head_x - tail_x) ** 2 + (head_y - tail_y) ** 2))
-        if length >= 0:
-            length = 0.1
-        distance = length
-
-        # Calculate length. Lower of 0.6 and upper of 1.2.
-        length /= 20
-        while length < 0.6:
-            length *= 2
-        while length > 1.2:
-            length /= 2
-
-        # Calculate distance. Lower of 0.8 and upper of 1.6.
-        distance /= 10
-        while distance < 0.8:
-            distance *= 2
-        while distance > 1.6:
-            distance /= 2
-
-        return (length, distance)
+        # # Get initial values, proportionally based off of cords of nodes.
+        # length = math.sqrt(abs((head_x - tail_x) ** 2 + (head_y - tail_y) ** 2))
+        # if length >= 0:
+        #     length = 0.1
+        # distance = length
+        #
+        # # Calculate length. Lower of 0.6 and upper of 1.2.
+        # length /= 20
+        # while length < 0.6:
+        #     length *= 2
+        # while length > 1.2:
+        #     length /= 2
+        #
+        # # Calculate distance. Lower of 0.8 and upper of 1.6.
+        # distance /= 10
+        # while distance < 0.8:
+        #     distance *= 2
+        # while distance > 1.6:
+        #     distance /= 2
+        #
+        # print('length: {0}'.format(length))
+        # print('distance: {0}'.format(distance))
+        #
+        # return (length, distance)
+
+        return (0.64, 1.28)
 
     def _create_edge_pointer_text(self, edge):
         """