Fix for shadow rendering and GS Alpha handling for dither effects.#86
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Add GS alpha-aware sprite rendering for effect paths such as finder dither. Mode 0x41 now uses a two-pass approximation of (Cd - Cs) * As + Cd instead of normal sprite blending, fixing the overly strong camera fuzz. Also supports additive/subtractive/destination boost modes and restores normal sprite state after special draws.
wagrenier
approved these changes
Jun 22, 2026
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Dither / finder effects
MikuPan now handles several PS2 GS alpha blend modes explicitly for 2D sprite/effect rendering instead of routing everything through the normal alpha blend path.
This fixes the camera/finder dither effect, which was previously drawn as an overly strong noisy overlay. The finder dither uses GS alpha mode 0x41, equivalent to:
(Cd - Cs) * As + CdThe renderer now supports the relevant GS alpha paths, including normal alpha, additive, subtractive, destination boost, and the destination-minus-source mode used by the finder dither. A small helper shader is used for the destination-alpha contribution needed by the 0x41 approximation.
Shadows
This also fixes several shadow rendering issues: