Fix couples spacing

geneit_app/src/widgets/simple_family_tree/SimpleFamilyTree.tsx

@@ -26,13 +26,28 @@ interface SimpleTreeNode {
   member: Member;
   spouse?: SimpleTreeSpouseInfo;
   down: SimpleTreeNode[];
+
+  /**
+   * The width of the parent and its children
+   */
   width: number;
+
+  /**
+   * The width of the parents
+   */
+  parentWidth: number;
+
+  /**
+   * The sum of the width of the children
+   */
+  childrenWidth: number;
 }
 
 /**
  * Get the width of a member card
  */
-function memberCardWidth(m: Member): number {
+function memberCardWidth(m?: Member): number {
+  if (!m) return 0;
   const nameWidth = getTextWidth(m.fullName, NAME_FONT);
   const birthDeathWidth = getTextWidth(m.displayBirthDeath, BIRTH_FONT);
   return Math.max(FACE_WIDTH, nameWidth, birthDeathWidth);
@@ -58,7 +73,7 @@ function buildSimpleDownTreeNode(
     );
   else childrenToProcess = [];
 
-  const node = {
+  const node: SimpleTreeNode = {
     down:
       childrenToProcess?.map((c) => buildSimpleDownTreeNode(c, depth - 1)) ??
       [],
@@ -69,20 +84,33 @@ function buildSimpleDownTreeNode(
           member: lastCouple.member,
         }
       : undefined,
+    parentWidth: -1,
+    childrenWidth: -1,
     width: -1,
   };
 
   // Compute current level width
-  let levelWidth =
-    memberCardWidth(node.member) +
-    (node.spouse ? SPOUSE_SPACING + memberCardWidth(node.spouse.member) : 0) +
-    CARD_SPACING;
+  let levelWidth: number;
+  if (node.spouse) {
+    levelWidth =
+      CARD_SPACING +
+      SPOUSE_SPACING +
+      2 *
+        Math.max(
+          memberCardWidth(node.member),
+          memberCardWidth(node.spouse.member)
+        );
+  } else {
+    levelWidth = memberCardWidth(node.member) + CARD_SPACING;
+  }
 
   // Compute down level width
   const downWidth =
     SIBLINGS_SPACING * node.down.length +
     node.down.reduce((prev, n) => prev + n.width, 0);
 
+  node.parentWidth = levelWidth;
+  node.childrenWidth = downWidth;
   node.width = Math.max(levelWidth, downWidth);
   return node;
 }
@@ -141,18 +169,12 @@ function NodeArea(p: {
   childrenLinkDestY?: number;
   node: SimpleTreeNode;
 }): React.ReactElement {
-  const parent_x_offset =
-    p.x +
-    Math.floor(
-      (p.node.width -
-        (memberCardWidth(p.node.member) +
-          (p.node.spouse
-            ? SPOUSE_SPACING + memberCardWidth(p.node.spouse.member)
-            : 0))) /
-        2
-    );
+  let parent_x_offset: number;
 
-  let downXOffset = p.x;
+  parent_x_offset = p.x + center(p.node.width, p.node.parentWidth);
+
+  let unusedChildrenWidth = p.node.width - p.node.childrenWidth;
+  let downXOffset = p.x + Math.floor(unusedChildrenWidth / 2);
 
   let endFirstFaceX =
     parent_x_offset +
@@ -160,7 +182,9 @@ function NodeArea(p: {
     FACE_WIDTH;
 
   let beginingOfSecondCardX =
-    parent_x_offset + memberCardWidth(p.node.member) + SPOUSE_SPACING;
+    parent_x_offset +
+    p.node.parentWidth -
+    memberCardWidth(p.node.spouse?.member);
 
   let beginSecondFaceX =
     p.node.spouse &&