[rshapes] DrawRectangleRoundedLines() results not aligned with DrawRectangleRounded()

[Kaehvaman]

• [*] I tested it on latest raylib version from master branch
• [*] I checked there is no similar issue already reported
• [*] I checked the documentation on the wiki
• [*] My code has no errors or misuse of raylib

Issue description

DrawRectangleRoundedLines draws weird unequal corners and is taller and wider than DrawRectangleRounded, which draws identical corners.
DrawRectangleRoundedLinesEx with lineThick != 1 works as expected, so the issue is linked to lineThick of 1 pixel.

Environment

Windows 10
Visual Studio 2022
MSVC
C language
raylib.lib from v5.5 release
INFO: GL: OpenGL device information:
INFO: > Renderer: AMD Radeon RX 6750 XT
INFO: > Version: 3.3.0 Core Profile Context 24.10.1.241007
INFO: > GLSL: 4.60

Issue Screenshot

Code Example

Rectangle roundRect = { 100, 250, 185, 36 };
DrawRectangleRounded(roundRect, 0.5f, 6, BLACK);
DrawRectangleRoundedLines(roundRect, 0.5f, 6, ORANGE);

[raysan5]

I think the issue is related to an off-by-one-pixel on lines calculations and I'm afraid that's a GPU-driver dependant issue, very difficult to address. Related to this, we have DrawRectangleLines() that still fails after many many changes and tries to solve the off-by-one-pixel issue...

[Kaehvaman]

Wow, never expected a driver to break such a simple thing

[Kaehvaman]

Updating to 24.12.1 driver didn't fix the issue :(