GXTexCoord[n][t]

• Category: Geometry and Vertex
• Matrix Status: Implemented
• Matrix Notes: Verified descriptor-ordered TEX0..TEX7 routing for immediate direct/indexed family, with per-attribute fixed-point scaling and per-vertex phase reset.
• Matrix Link: Gfx-GX-API-Matrix

Official SDK (Reference)

• Manual root: reference/rvlsdk/man/en_US/gx
• Primary SDK source area: demos/PikminDemo/src/gx (GC-style Dolphin GX source)
• Notes:
  • Confirm official signature/prototype
  • Confirm documented side effects (register/state updates)
  • Confirm special behavior and edge cases from manual

libPorpoise Implementation

• Runtime implementation area: src/gx
• Public API surface: include/dolphin/gx
• Notes:
  • Confirm API signature matches SDK
  • Confirm state writes match SDK semantics
  • Confirm backend behavior in PC renderer path

SDK vs Porpoise Diff

• Signature parity:
  • SDK:
  • Porpoise:
• Behavioral parity:
  • SDK:
  • Porpoise:

• Known divergence:

Validation Checklist

• GX demo coverage checked
• Pikmin usage path checked
• Matrix status updated if needed
• Notes updated with concrete file/function references

Working Notes

• Confirmed runtime behavior in src/gx/pc_gx.c:
  • Added descriptor-order texcoord selection (pc_gx_current_texcoord_attr) for immediate API calls.
  • Added texcoord phase advance/reset (pc_gx_advance_texcoord_phase, reset on GXBegin and each new vertex in GXPosition3f32).
  • Updated GXTexCoord2* fixed-point variants to use selected attribute frac, not hardcoded GX_VA_TEX0.
  • Updated GXTexCoord1x16/1x8 to read from selected texcoord array/format (GX_VA_TEX0..GX_VA_TEX7) instead of TEX0-only.