For reference:
In this case, it looks like you’ve got a few white edge pixels that have a really low alpha value.
Masked means that alpha is treated like a binary mask, values below the threshold are treated as 0, and values above are treated as 1. Objects rendered with a masked material can block other pixels and are generally faster than translucent draws on desktop GPUs (tiled GPUs in mobile don’t care). They also don’t have any special sorting issues, but they don’t look good if you have an actual gradient in alpha.
Translucent lets you have arbitrary alpha values, but it opens you up to sorting issues, etc…, but it’s the right choice for any sprites that have translucent regions or smooth gradients.
Opaque is the fastest of all, but it draws every pixel exactly from the source texture and totally ignores alpha. This is useful for shapes that have nice sharp edges on a square grid and can help with fill rate issues, but it’s usually easier to use the Diced mode for render geometry if you want to cut out large solid areas, rather than do it manually.
Cheers,
Michael Noland