Gfx GX Fn GXGetViewportv - wowjinxy/libPorpoise GitHub Wiki

GXGetViewportv

  • Category: Transformation and Matrix
  • Matrix Status: Implemented
  • Matrix Notes: Verified viewport vector getter order/size (GX_VIEWPORT_SZ) and SDK-style strict pointer semantics (no fail-soft NULL guard).
  • 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/GXGetViewportv.html and SDK source in reference/gx/GXTransform.c.
  • SDK behavior:
    • Copies current viewport state into vp[0..5] (left, top, width, height, nearz, farz).
    • Uses assert-style pointer contract (ASSERTMSG(vp, GXERR_GET_NULL_PTR)), not fail-soft return.
  • Runtime parity update in src/gx/pc_gx.c:
    • Removed defensive if (!vp) return; from GXGetViewportv.
    • Kept output layout/order unchanged and SDK-aligned.