NV2A/Vertex attributes

This article documents the attribute types which are supported by the Xbox GPU.

Normalized unsigned byte (D3D)

Unsigned bytes aranged as ZYXW (BGRA) in memory (Also see this GL extension). This is commonly used with an attribute count of 4. FIXME: Does this still work with attribute count =/= 4 ? Each byte will be mapped into the range 0.0 to 1.0. FIXME: Verify

Normalized unsigned byte (GL)

Unsigned bytes arranged as XYZW (RGBA) in memory. Each byte will be mapped into the range 0.0 to 1.0. FIXME: Verify

Normalized short

Shorts, arranged as XYZW. Each short will be mapped into the range -1.0 to 1.0 FIXME: Verify

Float

IEEE-754 single precision float arranged as XYZW. FIXME: What happens to NaN or denormals?

Short

Shorts, arranged as XYZW. Each short will be mapped into the range -32768.0 to 32767.0 FIXME: Verify

Compressed normal

Each 32 bit attribute is consisting of 11 bit X, 11 bit Y, 10 bit Z. Each component is signed and will be mapped into the range -1.0 to 1.0. FIXME: Verify FIXME: Is the attribute count ignored?