Diagonal selected exterior edges of a wireframe mesh appear wavy in the UI #120532

New Issue

Chad-Faragher · 2024-04-11T17:31:41+02:00

Chad-Faragher commented

2024-04-11 17:31:41 +02:00

System Information
Operating system: Windows-10-10.0.19045-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 2080 Ti/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 536.23

Blender Version
Broken: version: 4.1.0, branch: blender-v4.1-release, commit date: 2024-03-25 20:42, hash: 40a5e739e270
Worked: (newest version of Blender that worked as expected)

Short description of error
Diagonal selected thick (exterior) edges of a wireframe mesh appear wavy in the user interface. Unselected, thin, interior edges appear smooth and correct. It appears to be a bug in the user interface wireframe view that is evident when it draws thick nearly-diagonal lines.

Exact steps for others to reproduce the error
Add a cone with 4 segments, view in wire-frame mode, select the cone, and rotate the view so that the edges of the cone are approximately (but not exactly) diagonal in the viewport.

Extended Details

These edges are wavy

These edges are straight

The diagonal edges are wavy.

This is the base of a cone. The edges that are oriented diagonally in the viewport appear wavy.

Even at high resolution the waviness is visible

This is, of course, a very large image. You'll want to view it at 1:1 size on your monitor to see the effect.

Closeup of the effect

There is severe "roping" that is beyond the problems of antialiasing. This line has a cross-sectional height of 4 pixels and the shader (or whatever is rendering this line) is clearly choosing the wrong colours while rendering it. In my opinion, there is a bug in the rendering of thick lines in the user interface.

If you look at a horizontal cross-section, you'll notice that the pixels go from light to dark to light to dark. That's just wrong. It gives the appearance that the slope of the line is completely inverted, giving a wavy effect.

I suspect that there may be line drawing code in the UI with a fancy shader (or whatever draws these antialiased lines) that is close but very distractingly not correct.

**System Information** Operating system: Windows-10-10.0.19045-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 2080 Ti/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 536.23 **Blender Version** Broken: version: 4.1.0, branch: blender-v4.1-release, commit date: 2024-03-25 20:42, hash: `40a5e739e270` Worked: (newest version of Blender that worked as expected) **Short description of error** Diagonal selected thick (exterior) edges of a wireframe mesh appear wavy in the user interface. Unselected, thin, interior edges appear smooth and correct. It appears to be a bug in the user interface wireframe view that is evident when it draws thick nearly-diagonal lines. **Exact steps for others to reproduce the error** Add a cone with 4 segments, view in wire-frame mode, select the cone, and rotate the view so that the edges of the cone are approximately (but not exactly) diagonal in the viewport. **Extended Details** ### These edges are wavy [![Orange selected diagonal edges are wavy][1]][1] ### These edges are straight [![Black unselected diagonal edges are straight][2]][2] ### The diagonal edges are wavy. This is the base of a cone. The edges that are oriented diagonally in the viewport appear wavy. [![Orange diagonal edges of cone base are wavy][3]][3] ### Even at high resolution the waviness is visible This is, of course, a very large image. You'll want to view it at 1:1 size on your monitor to see the effect. [![Still looks bad even at high resolution][4]][4] ### Closeup of the effect There is severe "roping" that is beyond the problems of antialiasing. This line has a cross-sectional height of 4 pixels and the shader (or whatever is rendering this line) is clearly choosing the wrong colours while rendering it. In my opinion, there is a bug in the rendering of thick lines in the user interface. [![Close up of severe roping artifact][5]][5] If you look at a horizontal cross-section, you'll notice that the pixels go from light to dark to light to dark. That's just wrong. It gives the appearance that the slope of the line is completely inverted, giving a wavy effect. [![Detailed close up][6]][6] I suspect that there may be line drawing code in the UI with a fancy shader (or whatever draws these antialiased lines) that is close but very distractingly not correct. [1]: https://i.sstatic.net/4aqmaqiL.png [2]: https://i.sstatic.net/LRv4zV5d.png [3]: https://i.sstatic.net/bTk1brUr.png [4]: https://i.sstatic.net/LhxHbJUd.png [5]: https://i.sstatic.net/4hRurg7L.png [6]: https://i.sstatic.net/ZAkaCImS.png

example.blend

866 KiB

Chad-Faragher added the

labels 2024-04-11 17:31:41 +02:00

Iliya Katushenock added the