How do you reverse a gradient in Paint.net?

To reverse a gradient in Paint.net, right-click on one of the control nubs after drawing the gradient. This action swaps the primary and secondary colors, effectively reversing the gradient's direction.

Here's a more detailed explanation:

1. Draw your gradient: Use the Gradient tool in Paint.net to create your initial gradient.
2. Locate the Control Nubs: After releasing the mouse button, you'll see small squares (control nubs) at either end of the gradient line.
3. Reverse the Gradient: Right-click on either of these control nubs. This immediately switches the positions of your primary and secondary colors within the gradient. What was once the starting color becomes the ending color, and vice versa.

This provides a quick and easy way to change the gradient's direction without having to redraw it.