Lines Offsetting with Zoom

So my situation is, I drew a right-angle triangle at an angle of 0.5 degrees, made up of a straight horizontal line, a very short vertical line and the hypotenuse at a very small slope. Then I drew a straight vertical line at the midpoint of the horizontal line and ended it where it intersects the hypotenuse.

The problem is, I am absolutely positive these lines are drawn in the correct positions, but when I zoom into where the vertical line at the midpoint intersects the hypotenuse, the vertical line starts shrinking away from it; they no longer touch. When I click the hypotenuse while zoomed in, nothing happens, but when I click where it SHOULD BE (at the top of the vertical line), the hypotenuse gets selected and snaps it back to the correct location. Deselecting the hypotenuse returns it to its offset position. No issues are present (or just not noticeable) when I'm zoomed further out.

I've tested what happens when I increase the angle to 45 degrees and the only difference is I have to zoom in further before the lines offset. The problem doesn't occur when I attach two lines together at their ends. The only time the problem occurs is when I try to connect a line to a sloped line anywhere but at its endpoints.

I've tried regenerating the model, loading other people's profiles (who don't have this issue), redrawing it on drawings I've completed in the past, restarting my computer, nothing has fixed it. When my co-workers tried it on their computers, they did not have the same problem.

I'm running AutoCad 2009 on Windows 7.

Any help would be much appreciated.

Thanks,

Harrison

The error is not really there. It's a graphics display issue, and similar questions have come up many times on this forum. Have you seen what it does to a line perpendicular to an arc? I bet it's worse. Either way, the printed plot results will be fine, assuming your lines are thin enough to differentiate a 1/2 degree angle.

Have you tried using a closed polyline for your triangle? That might improve the display quality. Since a closed polyline is a single entity, it cannot be separated.

Is hardware acceleration on, or off? Whichever, try switching it the other way and see what happens.

The fact that regen doesn't work all the time tells me it could be a graphics memory limitation. I don't know what your graphics card can do, but it sounds like handling zoom at a magnification small enough to see this phenomenon is one thing it can't do.

I turned the hardware acceleration off and it fixed the issue, thanks!

I turned the hardware acceleration off and it fixed the issue, thanks!