GXClearVtxDesc

• Category: Geometry and Vertex
• Matrix Status: Implemented
• Matrix Notes: SDK parity pass done: clear resets descriptor state and restores default GX_VA_POS = GX_DIRECT.
• Matrix Link: Gfx-GX-API-Matrix

Official SDK (Reference)

• Manual page: E:/GPT5/Porpoise_SDK/libPorpoise/reference/man/gfx/gx/Geometry/GXClearVtxDesc.html
• Related pages:
  • E:/GPT5/Porpoise_SDK/libPorpoise/reference/man/gfx/gx/Geometry/GXSetVtxDesc.html
  • E:/GPT5/Porpoise_SDK/libPorpoise/reference/man/gfx/gx/Geometry/GXSetVtxDescv.html
• SDK source parity check area: E:/GPT5/ACGC-PC-Port-Debug-Stuff/src/static/dolphin/gx/GXAttr.c
• Notes:
  • Manual signature: void GXClearVtxDesc(void).
  • Manual text says all attributes are set to GX_NONE.
  • Dolphin GX source implementation then explicitly sets position descriptor field to direct (GX_VA_POS = GX_DIRECT) and marks descriptor dirty.

libPorpoise Implementation

• Runtime implementation area: E:/GPT5/Porpoise_SDK/libPorpoise/src/gx/pc_gx.c
• Legacy implementation area: E:/GPT5/Porpoise_SDK/libPorpoise/src/gx/GXGeometry.cpp
• Public API surface: E:/GPT5/Porpoise_SDK/libPorpoise/include/dolphin/gx/GXGeometry.h
• Notes:
  • Signature matches SDK.
  • ACPC/GX backend clears descriptor table and restores GX_VA_POS = GX_DIRECT.
  • Legacy backend mirrors the same default restore.

SDK vs Porpoise Diff

• Signature parity:
  • SDK: void GXClearVtxDesc(void)
  • Porpoise: same
• Behavioral parity:
  • SDK source: clears descriptor state and leaves GX_VA_POS direct-enabled.
  • Porpoise: same in both backends.
• Known divergence:
  • Manual prose says "all attributes to GX_NONE", but Dolphin source keeps position direct as post-clear default. Porpoise follows source/runtime behavior for compatibility.

Validation Checklist

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

Working Notes

• SDK source reference lines: GXAttr.c around GXClearVtxDesc show vcdLo reset plus POS field set.