nx_dxbc.nx

nx_dxbc.nx -- D1 of the D3D-game ladder: a real DXBC (DirectX ByteCode) container + shader-token DECODER. A Windows D3D9-11 game ships COMPILED shaders as DXBC blobs; running them starts with PARSING them. This decodes: CONTAINER: "DXBC" magic, 16B checksum, u32 1, u32 total_size, u32 chunk_count, u32[chunk_count] offsets, then chunks each = FourCC tag + u32 byte-size + payload. (little-endian, the real on-disk layout.) SHADER CHUNK (SHEX/SHDR): u32 version (program-type in high nibble: 0=pixel 1=vertex ...) + u32 dword-length, then a stream of instruction tokens: token = [opcode 0:10][length 24:30]; length = dwords incl the token, so the next instruction is at +length. We classify the opcode (dcl_*, mov, add, mul, mad, dp3/dp4, sample, ret) and count instructions -- the basis D2 lowers to our ISA / SPIR-V. Pure integer, bounds-checked (defensive at the boundary: this is untrusted external input). license_tier: ORIGINAL