C3D 2020 - Curves Not Displayed Correctly Bug

[Cadguru42]

So the bug that started with 2016 where having multiple viewports causes curves to not display correctly when far from the origin still has not been fixed in 2020.2 after 4.5 years.

Curves still not displaying correctly with multiple viewports.

How has Autodesk allowed their CAD program to go 4.5 years without fixing a bug related to displaying of basic geometry? I think when they "upgraded" the graphics engine in 2016 it uses the 3ds Max/Revit display engine when multiple viewports are used, which is single floating point and can help explain this major defect with a CAD program.

[joshua.phillips28DD7]

I'm still having this problem. Is there a fix now, in 2023?

[Asmir]

1. Set "whiparc" to "0". 2. Type "graphicsconfig" and un-check the "High quality geometry (for capable devices)" box.

[Cadguru42]

---

@Asmir wrote:

1. Set "whiparc" to "0". 2. Type "graphicsconfig" and un-check the "High quality geometry (for capable devices)" box.

---

That does not "fix" the issue. Turning off the advanced functions of these expensive graphics cards does not fix the fundamental bug that Autodesk introduced when they setup AutoCAD to use single-floating point precision when there are two or more viewports. 

And no, the bug still exists even with AutoCAD 2023.1.2 and Civil 3D 2023.2 Update. 

Curves still display incorrectly in C3D 2023.2 when far from the origin.

Autodesk doesn't care about their core CAD program when they let something this fundamental go on for over 7 years.

[Asmir]

Is it possible for you to upload dwg so i can check it on my PC

[Cadguru42]

---

@Asmir wrote:

Is it possible for you to upload dwg so i can check it on my PC

---

You can create this on your own in any drawing using the OOTB templates. Create an alignment, arc, or a polyline with curves far from the origin. In the example above, I created an alignment near 3000000, 750000 with curves. Split the viewport to have at least two at a time. Zoom in on the PT and you'll notice that the curve/arc will not show tangent.

Refer to my original post almost eight years ago when this showed up.

https://forums.autodesk.com/t5/civil-3d-forum/c3d-2016-curves-incorrectly-displayed-with-multiple-vi...