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pizzapartytime / Vortex

Build with Bug Fixes of Unreleased Mega Drive game Out of the Vortex
Creative Commons Zero v1.0 Universal
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Crash on Second Form of Final Boss #2

Closed pizzapartytime closed 2 months ago

pizzapartytime commented 2 months ago

TheMightyC7 has mentioned a game crash on second form of Final Boss.

pizzapartytime commented 2 months ago

Was able to proc an address bus crash with Rebel by getting it the Mantis's Face and punching repeatedly

Research:

This is a 68K addressing bug where the game is trying to load 16bits from an odd memory address which is not physically possible with this processor.

a5 => SPR.Ennemi1 (Big Nano) SPR.Stun_Pos(a5) => a0 // Looks like this variable is total garbage for Big Nano

Monster uses Ennemi.Stun_17 address for SPR.Stun_Pos(a5) Monter SPR.Stun_Vbl(a5) == $FF Monster SPR.Stun_type(a5) == 17

pizzapartytime commented 2 months ago

Ok getting down to it:

SPR.Tbl_Stun is being loaded as cleared out for Mantis Nano in Initialization Variables d'un Ennemi, which is leading to SPR.Stun_Pos to be loaded with garbage.

pizzapartytime commented 2 months ago

Fixed by giving Mantis Nano (Nano3) the most used Enemy SPR.Tbl_Stun address, will be in v0.03