[rshapes] Pixel perfect issue

[Bigfoot71]

This issue is about the discussions regarding the offset problems when rendering lines, see:

• [rshapes] DrawRectangleRoundedLines() results not aligned with DrawRectangleRounded() #4601
• [rshapes] Fix pixel offset issue with line drawing #4666
• [rshapes] Fix pixel offset issue with DrawRectangleLines #4669

I noticed that the line rlTranslatef(0.375, 0.375, 0) is commented out in BeginDrawing().

AFAIK, this 0.375 offset was used to align coordinates with the centers of pixels, as NVIDIA and ATI had different rounding conventions, this offset worked for both manufacturers.

However, I have doubts about the explanation in the comment stating that this line is no longer needed with OpenGL 3.3+:

//rlTranslatef(0.375, 0.375, 0); // HACK for 2D pixel-perfect drawing on OpenGL 1.1
// NOTE: Not required with OpenGL 3.3+

I suspect that rounding conventions might have been standardized between manufacturers, making the 0.375 offset unnecessary, but I haven't found confirmation on this.

Based on my knowledge, with OpenGL, and here in the case of orthographic 2D projection, integer coordinates still correspond to the corners of the pixels, not their centers, so the offset for pixel-perfect rendering might still be needed.

Do I lack any additional information on this?

[raysan5]

@asdqwe Thanks for the reference! Very interesting!

@Bigfoot71 I think we can keep as it is for now, let's see if it pops up again in the future dramatically afffecting some real application...