Dragging nodes causes links to lose curve and become straight — curves should be preserved #613
Description
Description
When using curved edges in ngx-graph (e.g., curveBundle.beta(0.85)), the edges render beautifully on initial layout. However, once a user drags a node, all connected links lose their curvature and become straight lines. This breaks the visual flow and UX of graphs relying on curves.
### Steps to Reproduce
- Render a graph with
[curve]="curveBundle.beta(0.85)" - Observe that edges are nicely curved
- Drag any node
- Observe that connected links become straight lines immediately after
### Expected Behavior
Edges should retain their curvature even after node dragging.
If the user has specified a custom curve using [curve] or <ngx-graph-custom-curve>, the library should honor it post-drag.
### Actual Behavior
Dragging causes edges to lose their curve — likely because the library switches to manual layout and defaults to linear interpolation.
How can I fix this ?
