The rounded rectangle in fill mode has strong aliasing.

[yangsiyu]

* fill mode

2024-06-10_09-19.png (58.72 KiB) Viewed 1938 times

* line mode

2024-06-10_09-26.png (72.58 KiB) Viewed 1938 times

Looking at the source image, they are quite different.

[yangsiyu]

Drawing filled circles also has the same issue.

[slime]

Lines have their own custom antialiasing/smoothing applied by default (the "smooth" line style) which is only for lines and not other things like images or filled shapes. To have antialiasing on filled shapes, two common approaches are to enable MSAA on the window or to draw a line shape at the same spot as the filled shape.

[yangsiyu]

Lines have their own custom antialiasing/smoothing applied by default (the "smooth" line style) which is only for lines and not other things like images or filled shapes. To have antialiasing on filled shapes, two common approaches are to enable MSAA on the window or to draw a line shape at the same spot as the filled shape.

Thanks

[RNavega]

Also see this alternative, drawing a quad Mesh and using a shader for antialiasing the round corners:
viewtopic.php?p=259055#p259055

If you need the rectangle to be drawn while rotated then you'd need a different shader, one that smooths not only the round corners but also the straight sides.