acdream's TranslucencyKindExtensions.FromSurfaceType picked Additive
first (priority order). Retail's D3DPolyRender::SetSurface at
0x0059c4d0 (decomp 425083+) has a different resolution: when the
Translucent flag (0x10) is set AND either Base1ClipMap (0x04) is set
OR the surface would otherwise be opaque (no Additive/Alpha/InvAlpha),
the blend is *forced* to (SrcAlpha, InvSrcAlpha) — i.e. standard
alpha-blend, not additive. Verbatim from decomp lines 425246-425260:
if ((curr_surface_type & 0x10) != 0) {
if (skipChk != 0 || ebx == 0 || arg3 == 1) {
edi_2 = BLEND_SRCALPHA; // src
ebp = BLEND_INVSRCALPHA; // dst ← alpha-blend
}
curr_alpha = _ftol2(translucency * 255);
}
Where `arg3 == 1` is set after the Base1ClipMap branch and `ebx == 0`
is the opaque-base case in Branch 2.
Concrete impact: Dereth's inner cloud sheet GfxObj 0x01004C35 uses
surface 0x08000023 with Type=0x10114 (B1ClipMap|Translucent|Alpha|
Additive). Retail renders it alpha-blend; acdream was rendering it
additive. Additive on a dark cloud texture only brightens the
background — sun shines through unchanged — which doesn't match
retail's denser cloud appearance.
Rain surface 0x080000C5 (Type=0x10112 = B1Image|Translucent|Alpha|
Additive, NO ClipMap) hits Branch 1 → Additive, ClipMap branch is
skipped, the Translucent override doesn't fire (arg3 stays 0) → stays
Additive. Visual rain rendering is unchanged.
User reported no visible difference at the verification launch; the
remaining cloud-density gap likely lives in the PES particle layer
(issue #28). Keeping this fix because the classification is now
decomp-correct regardless of immediate visual impact — issue #29
documents the residual gap.
1227 tests pass.
375065ba94