Via another Viewpoint topic (Can’t see magnifiers in VP within PL3 it has become apparent to me that the Mac combination of PhotoLab & Viewpoint 3 offer features not found with the equivalent Windows products. Specifically this concerns the ability, within all four of the perspective correction tools (Horizon, Force Parallel, Rectangle and 8 Points) to draw the correction lines. With the Mac software this feature exists. With the Windows software this only exists for the Horizon and Rectangle corrections. For the other two corrections (Force Parallel and 8 Points) you have to drag each of the correction line endpoints (4, or 8 respectively) to the desired positions. The ability to draw the correction lines (and then only dragging endpoints for fine positioning if necessary) is a quicker process than having to drag all of the endpoints from the outset.
My request is that the Windows implementation offers the same capabilities as already present with the Mac version.
I use PL3 on Windows but I can’t draw lines at all, i.e. no matter which I choose (horizon, force parallel, rectangle or 8 points) when I click and drag to draw a line nothing happens.
That seems even odder than the difference between the Windows and Mac versions that I see. I doubt it’s relevant to this difference but I’m running Windows 10 Home Edition version 2004 (with all subsequent relevant updates installed).
If might be worth lodging a support ticket to get to the bottom of why you can’t draw lines with any of the tools. As you might have spotted from the linked topic, I only became aware the other day that I could draw lines with the Rectangle tool, but I’ve been using the line drawing with the Horizon tool since I started using Viewpoint. I find I use the Horizon tool most frequently, followed by Force Parallel, followed by 8 Points with the Rectangle tool as the least used
If you activate the Horizon tool then you should be able to draw your own horizon line simply by clicking-and-dragging with your mouse from any starting-point within your image … If not then there’s definitely something wrong with your installation.
Hmm because I made the post I did and loudly declared I couldn’t draw lines with any of the tools because I couldn’t, today PL for Windows is behaving as it should No, I’ve not made any changes / applied any updates. It just must be Windows WirednessTM#I’veLost Count
In summary:
when I select the horizon tool I can click and drag to draw a line
within the Viewpoint menu, when I select ‘rectangle’ I can draw a new rectangle where ever I want by click and dragging
when I use ‘force parallel’ and 8 points though, I can’t click and drag to draw new lines
because I made the post I did and loudly declared I couldn’t draw lines with any of the tools because I couldn’t, today PL for Windows is behaving as it should 
No, I’ve not made any changes / applied any updates. It just must be Windows WirednessTM 