Target layer: Polygon

Description:  Draw a polygon, the start point should be in the polygon to be reshaped (target polygon). When the sketch is finished (on double click) the existing polygon that contains the start point of the sketched polygon is reshaped with the sketched polygon according to the priority set in the Control Panel or using the Hot Key "A" when the tool is active:

• Priority = "Low" - only the portions of the sketched polygon that do not overlap existing polygons are added to the target polygon. Ideal for filling gaps between neighboring polygons,
• Priority = "High" - the target polygon is reshaped with the entire sketched polygon. The existing polygons or portions of them  that overlap the sketched polygon are erased - the polygon topology is preserved.

Advantages: 

• Preserves the polygon topology
• Ideal tool for filling gaps
• No snapping needed to maintain topology while reshaping
• No need to select the polygon to be reshaped beforehand

Hot Keys (Pressing these keys when the tool is active will allow changing  the parameters used by the function): 

• "A" - sets the priority for the reshape polygon
  • Low
  • High 

Attribute Updates: The attributes of the original features will be preserved

Snapping: Supported. Uses the standard Editor snapping settings. For better results do not snap to features from currently edited layer.

Example:  

Input

Priority = "Low"- Only the gap is added to the target polygon

Priority = "High"- The target polygon is reshaped with entire sketched polygon. The portions of the existing polygons overlapping the sketch polygon are erased