Alphakill

Rsx is fairly close to pc gpu. Of course some functions are not exposed by api but they're often deprecated (and thus can be emulated otherwise) or performance related, giving hints to the hardware but doesn't change the output.
Alpha kill belongs to the first category : it discards a pixel when some comparaison operation on pixel alpha value is true.
The feature is used by virtually every game today to mimic grass, hairs,... Based on alpha component (="transparency&quot of a texture. Instead of relying on a fixed function the discard operation is moved to the shader.

There is an alpha I'll feature on texture although I don't know how it works. It's likely similar but happen when a texture is sampled instead of waiting shader has finished execution.

I'm worried about per camera facing value ref/function settings since it's not supported by d3d (2 sided stencil can only accept different ops and mask) but no rendering technics I'm aware of use this so it's likely not very used.

The bare metal memory access is the difficult thing to emulate because all pc api wrap memory object but it's common to every device you want to emulate.

About that alpha on texture feature does it have any name? Does RSX support destination alpha test or any exotic blending modes that require programmable blending with texture barrier to emulate like say PS2, PSP ,GC and even Saturn? Does it support alpha to coverage? I'm not sure I understand about that per camera function is that something related to the viewport? I remember hearing about something called Flip Control too. Does RSX still have register combiners in addition to shaders or was that already removed and finally does it support tessellation since I know Xenos does.