Line drawing

Can we have increments of 1 while drawing a line.

What is the context in which the user is drawing a new line? What tools are being used? What Diagram and Tool properties apply here? What constraints do you have on the drawing of these objects?

Are you talking about the FloorPlanner app? Floor Planner In that sample the lines are already limited to multiples of 10cm if the wall is being drawn horizontally or vertically.

Yes Its Floorpalnner App.How can i reduce it to 1cm ?

Basically you need to decrease the Model.modelData.gridSize property to 1.0. You might need to change the actual Diagram.grid so that its Panel.gridCellSize continues to be new go.Size(10, 10) or whatever you want.