Fix odd-sized pixel snapping

[adamscott]

Warning

This PR needs to be thoroughly tested before merging it.

This PR makes it so that it doesn't add 0.5 pixels to odd sized items before snapping them.

Fixes #94298.

Tests

• @KeyboardDanni's PixelPerfectTest.zip
• [4.3beta3] Sprite pivot changed since 4.3beta2 #94298's MRP
• Test some RichTextLabels FX

[KeyboardDanni]

Are we sure this is the right fix? Do we really want to change the behavior of odd pixels? I'd think we would want consistent rounding behavior for both even and odd pixels. I continue to be of the opinion that we should try to make the rounding behavior as simple as possible so that users aren't dealing with sudden surprises from corner cases.

What about the approach I suggested at #94298 (comment) ?

[KeyboardDanni]

Also the use of fmod here seems incorrect, as it returns a floating point remainder. It'd only perform rounding when the coordinate is exactly aligned with an even pixel, which kind of goes against the whole purpose of pixel rounding to begin with.