improve the merge diagrams

new_git_course/git_talk.md

@@ -203,12 +203,16 @@ omitting the `--global` allows configuration on a per-repo basis
 ## Merge and Rebase
 ### Merge
 \begin{tikzpicture}
+\draw
+    (-1, 0)node[] {main}
+    (-1, 1)node[] {auxiliary}
+    ;
 \draw[line width=.5pt]
     (0,0)node[draw, circle] (0) {}
     (1,0)node[draw, circle] (1) {}
     (2,0)node[draw, circle] (2) {}
     (3,1)node[draw, circle] (3) {}
-    (3,0)node[draw, circle] (4) {}
+    (3,0)node[draw, circle, red] (4) {}
     (4,1)node[draw, circle] (5) {}
     [-] (0) -- (1) -- (2) -- (4)
     [-] (2) -- (3) -- (5)
@@ -221,7 +225,7 @@ omitting the `--global` allows configuration on a per-repo basis
     (10,1)node[draw, circle] (3) {}
     (10,0)node[draw, circle] (4) {}
     (11,1)node[draw, circle] (5) {}
-    (12,0)node[draw, circle] (7) {}
+    (12,0)node[draw, circle, red] (7) {}
     [-] (0) -- (1) -- (2) -- (4) -- (7)
     [-] (2) -- (3) -- (5) -- (7)
     ;
@@ -230,13 +234,17 @@ omitting the `--global` allows configuration on a per-repo basis
 ### Rebase
 
 \begin{tikzpicture}
+\draw
+    (-1, 0)node[] {main}
+    (-1, 1)node[] {auxiliary}
+    ;
 \draw[line width=.5pt]
     (0,0)node[draw, circle] (0) {}
     (1,0)node[draw, circle] (1) {}
     (2,0)node[draw, circle] (2) {}
     (3,1)node[draw, circle] (3) {}
-    (3,0)node[draw, circle, red] (4) {}
-    (4,1)node[draw, circle] (5) {}
+    (3,0)node[draw, circle] (4) {}
+    (4,1)node[draw, circle, red] (5) {}
     [-] (0) -- (1) -- (2) -- (4)
     [-] (2) -- (3) -- (5)
     ;
@@ -245,11 +253,10 @@ omitting the `--global` allows configuration on a per-repo basis
     (7,0)node[draw, circle] (0) {}
     (8,0)node[draw, circle] (1) {}
     (9,0)node[draw, circle] (2) {}
-    (10,0)node[draw, circle, red] (4) {}
+    (10,0)node[draw, circle] (4) {}
     (11,1)node[draw, circle] (5) {}
-    (12,1)node[draw, circle] (6) {}
-    [-] (0) -- (1) -- (2) -- (4)
-    [-] (4) -- (5) -- (6)
+    (12,1)node[draw, circle, red] (6) {}
+    [-] (0) -- (1) -- (2) -- (4) -- (5) -- (6)
     ;
 \end{tikzpicture}