Auto scroll limitation in gojs diagram

GoJS
1

I have attached a video where auto scroll doesn’t occur properly.
When the node is dragged (at fast pace) immediately out of the document bounds, then the node is not visible within the canvas and the canvas doesn’t even auto scroll to that location to make the node visible.
Video Link
The video shows the demo.
Is there any solution to improve this behavior where user gets scrolled to that node location.

2

Auto-scrolling is only supposed to happen when the mouse is being dragged just inside the viewport. Any dragging that goes outside of the viewport (i.e. the canvas) might be interpreted as a drag-out from the diagram to some other HTML element.

3

Hi Walter thank you for the reply, is there any way to, fix via any alternative way to do it, like putting some logic into it, or modifying any inbuilt code.(any hot fix)
Thanks.

4

Something like this might work for you:

    $(go.Diagram, . . .,
      {
        "draggingTool.doMouseMove": function() {
          // do the standard behavior by calling the super method
          go.DraggingTool.prototype.doMouseMove.call(this);
          // if dragging-out from the diagram is not allowed, and
          // if mouse is outside of viewport
          if (!this.diagram.allowDragOut &&
              !this.diagram.viewportBounds.containsPoint(this.diagram.lastInput.documentPoint)) {
            this.diagram.ensureBounds();
            var vp = this.diagram.lastInput.viewPoint;
            var dp = this.diagram.position.copy();
            if (vp.x < 0) dp.x -= 10; else if (vp.x > 0) dp.x += 10;
            if (vp.y < 0) dp.y -= 10; else if (vp.y > 0) dp.y += 10;
            this.diagram.position = dp;  // scroll in the direction of the mouse
          }
        },
        . . .

This is not really auto-scrolling because there’s no timer to continue moving the Diagram.position while the mouse is stationary.

You might also want to fiddle with the value by which you scroll, instead of the hard-coded value of 10 document units.