continue connecting directly

d2layouts/d2dagrelayout/layout.go

@@ -261,6 +261,105 @@ func Layout(ctx context.Context, g *d2graph.Graph, opts *ConfigurableOpts) (err
 				}
 			}
 		}
+		points = points[startIndex:endIndex]
+		points[0] = start
+		points[len(points)-1] = end
+
+		edge.Route = points
+	}
+
+	for _, obj := range g.Objects {
+		if obj.LabelHeight == nil || len(obj.ChildrenArray) <= 0 {
+			continue
+		}
+
+		// usually you don't want to take away here more than what was added, which is the label height
+		// however, if the label height is more than the ranksep/2, we'll have no padding around children anymore
+		// so cap the amount taken off at ranksep/2
+		subtract := float64(go2.Min(rootAttrs.ranksep/2, *obj.LabelHeight+label.PADDING))
+
+		obj.Height -= subtract
+
+		// If the edge is connected to two descendants that are about to be downshifted, their whole route gets downshifted
+		movedEdges := make(map[*d2graph.Edge]struct{})
+		for _, e := range g.Edges {
+			currSrc := e.Src
+			currDst := e.Dst
+
+			isSrcDesc := false
+			isDstDesc := false
+
+			for currSrc != nil {
+				if currSrc == obj {
+					isSrcDesc = true
+					break
+				}
+				currSrc = currSrc.Parent
+			}
+			for currDst != nil {
+				if currDst == obj {
+					isDstDesc = true
+					break
+				}
+				currDst = currDst.Parent
+			}
+			if isSrcDesc && isDstDesc {
+				stepSize := subtract
+				if e.Src != obj || e.Dst != obj {
+					stepSize /= 2.
+				}
+				movedEdges[e] = struct{}{}
+				for _, p := range e.Route {
+					p.Y += stepSize
+				}
+			}
+		}
+
+		// Downshift descendents and edges that have one endpoint connected to a descendant
+		q := []*d2graph.Object{obj}
+		for len(q) > 0 {
+			curr := q[0]
+			q = q[1:]
+
+			stepSize := subtract
+			// The object itself needs to move down the height it was just subtracted
+			// all descendents move half, to maintain vertical padding
+			if curr != obj {
+				stepSize /= 2.
+			}
+			curr.TopLeft.Y += stepSize
+			// Edge should only move if it's not connected to the bottom side of the shrinking container
+			shouldMove := func(p *geo.Point) bool {
+				if curr != obj {
+					return true
+				}
+				return p.Y != obj.TopLeft.Y+obj.Height
+			}
+			for _, e := range g.Edges {
+				if _, ok := movedEdges[e]; ok {
+					continue
+				}
+				if e.Src == curr {
+					if shouldMove(e.Route[0]) {
+						e.Route[0].Y += stepSize
+					}
+				}
+				if e.Dst == curr {
+					if shouldMove(e.Route[len(e.Route)-1]) {
+						e.Route[len(e.Route)-1].Y += stepSize
+					}
+				}
+			}
+			for _, c := range curr.ChildrenArray {
+				q = append(q, c)
+			}
+		}
+	}
+
+	for _, edge := range g.Edges {
+		points := edge.Route
+		startIndex, endIndex := 0, len(points)-1
+		start, end := points[startIndex], points[endIndex]
 
 		// arrowheads can appear broken if segments are very short from dagre routing a point just outside the shape
 		// to fix this, we try extending the previous segment into the shape instead of having a very short segment
@@ -340,85 +439,6 @@ func Layout(ctx context.Context, g *d2graph.Graph, opts *ConfigurableOpts) (err
 		}
 	}
 
-	for _, obj := range g.Objects {
-		if obj.LabelHeight == nil || len(obj.ChildrenArray) <= 0 {
-			continue
-		}
-
-		// usually you don't want to take away here more than what was added, which is the label height
-		// however, if the label height is more than the ranksep/2, we'll have no padding around children anymore
-		// so cap the amount taken off at ranksep/2
-		subtract := float64(go2.Min(rootAttrs.ranksep/2, *obj.LabelHeight+label.PADDING))
-
-		obj.Height -= subtract
-
-		// If the edge is connected to two descendants that are about to be downshifted, their whole route gets downshifted
-		movedEdges := make(map[*d2graph.Edge]struct{})
-		for _, e := range g.Edges {
-			currSrc := e.Src
-			currDst := e.Dst
-
-			isSrcDesc := false
-			isDstDesc := false
-
-			for currSrc != nil {
-				if currSrc == obj {
-					isSrcDesc = true
-					break
-				}
-				currSrc = currSrc.Parent
-			}
-			for currDst != nil {
-				if currDst == obj {
-					isDstDesc = true
-					break
-				}
-				currDst = currDst.Parent
-			}
-			if isSrcDesc && isDstDesc {
-				stepSize := subtract
-				if e.Src != obj || e.Dst != obj {
-					stepSize /= 2.
-				}
-				movedEdges[e] = struct{}{}
-				for _, p := range e.Route {
-					p.Y += stepSize
-				}
-			}
-		}
-
-		// Downshift descendents and edges that have one endpoint connected to a descendant
-		q := []*d2graph.Object{obj}
-		for len(q) > 0 {
-			curr := q[0]
-			q = q[1:]
-
-			stepSize := subtract
-			// The object itself needs to move down the height it was just subtracted
-			// all descendents move half, to maintain vertical padding
-			if curr != obj {
-				stepSize /= 2.
-			}
-			curr.TopLeft.Y += stepSize
-			if curr != obj {
-				for _, e := range g.Edges {
-					if _, ok := movedEdges[e]; ok {
-						continue
-					}
-					if e.Src == curr {
-						e.Route[0].Y += stepSize
-					}
-					if e.Dst == curr {
-						e.Route[len(e.Route)-1].Y += stepSize
-					}
-				}
-			}
-			for _, c := range curr.ChildrenArray {
-				q = append(q, c)
-			}
-		}
-	}
-
 	return nil
 }