Horizontal offset in drawing pixels, after font scaling.
Added to the glyph's destination as given, with no rounding. On an upscaled low-resolution frame, round it: a fractional destination under nearest sampling makes the glyph's own pixels come out uneven, and differently so each frame, which reads as a shimmer rather than motion.
Vertical offset in drawing pixels, after font scaling. Rounds like GlyphEffectOutput.offsetX.
ReadonlytintMultiplicative tint; reset to opaque white before each call.
Mutable per-glyph output, reset before each call. Do not retain it.