November 2017 - last edited February 2018
Product: The Sims 4
Which language are you playing the game in? English
How often does the bug occur? Every time (100%)
What expansions, game packs, and stuff packs do you have installed? All
Steps: How can we find the bug ourselves? Place a roof (my example is the gabled roof). Click on a curvature point. The roof will immediately bottom out into the lowest curvature rather than waiting for you to adjust the curvature as you move the mouse while holding the tool. Click on the curvature point again, and create a concave curve that is shallower than the one the game automatically created. Release the tool and click again. The roof will be bottomed out again. Click on the curvature point again, and create a convex curve. Release the tool and click again. The roof will be snapped to its default straight angle (or tow a concave curve depending upon how much of a convex curve you created).
What happens when the bug occurs? Upon selecting the curvature toggle point, roof angles are being automatically changed by the game rather than by the user.
What do you expect to see? I expect to see a roof change curvature only when I adjust the curvature manually. Note that if you toggle SHIFT+C in order to enable additional roof curvature points, the undesired behavior no longer occurs. Ideally, you shouldn't need to toggle SHIFT+C to prevent it, however.
Have you installed any customization with the game, e.g. Custom Content or Mods? Never used.
Did this issue appear after a specific patch or change you made to your system? Yes
Please describe the patch or change you made. New in the 11/7/17 patch.
Video above demonstrates the problem. Workaround: before making adjustments to a roof, select it and press SHIFT+C. Then make any adjustments necessary.