GXLoadTexMtxImm

• Category: Transformation and Matrix
• Matrix Status: Partial
• Matrix Notes: Verified first-pass texture matrix load and corrected GX_MTX2x4 vs GX_MTX3x4 size handling; HW2 post-transform (GX_PTTEXMTX*) path remains unimplemented.
• 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

• Docs checked against reference/man/gfx/gx/Transform/GXLoadTexMtxImm.html and SDK source in reference/gx/GXTransform.c.
• Runtime checked in src/gx/pc_gx.c:
  • Accepts both GX_MTX2x4 and GX_MTX3x4 input forms.
  • GX_MTX2x4: copies first 2 rows and synthesizes row3 as [0,0,0,1] for backend use.
  • GX_MTX3x4: copies full 12 floats directly.
  • Marks texgen state dirty so updated matrix is applied to subsequent draws.
  • Matrix ID mapping currently targets first-pass texture matrices (GX_TEXMTX* / slot IDs); GX_IDENTITY is treated as fixed identity and not writable.
• Known divergence (keeps status Partial):
  • HW2 post-transform texture matrix IDs (GX_PTTEXMTX*) are not yet mapped/loaded in this backend path.