Is there a way in PhotoShop to start with a line segment, and automatically extend the line along the same direction/angle as the segment without defining an end point?

I have a photo of a house with siding. The lines of the siding show in the shade but not in the sunlight. I want (on a new layer) to draw in the missing parts of the siding lines retaining the individual angle of each one. I would love to be able to click on a start point, and mid point, and have the line continue out automatically along the same path.

Is this possible in Photoshop? If so, how?

TIA

In Photoshop use a small brush, click once on the start point, then press the SHIFT key and click the end point. Photoshop will draw a line for you.

Thanks for that suggestion, but it requires knowing the end point in advance.

I want to click the starting point and a mid point and have the line continue at that same angle out infinitely. My thought is to manually cut it off then exactly where I need it to end.

Is there a Photoshop tool or feature that will do this?

If you have Adobe CS (or Illustrator). You may be able to take your photo into Illustrator and create the lines on a separate layer there. You would certainly have more control with the line tool in Illustrator than the paint brush in Photoshop. You will be able to tweak the lines after they are drawn much easier. When done, pitch the photo layer and save as an EPS then Place that in in Photoshop and position as needed.