LiveSplit autosplitter for Lycanthorn II - Rain of Beasts.

• Load Removal
• Auto start
• Auto split points
  • Level entries/exits
  • Run end

• Auto split points
  • Key collection
  • Boss kills

Lycanthorn II is built with GZDoom 4.3.1. This engine is open source, which is always helpful when reverse engineering an application. To find the static values outlined below, I used the following process:

• Locate a reference to the target value in the source code which is close to a unique string literal.
• Using a reverse engineering tool such as x64dbg, search for the string literal in the game's exe.
• Locate the assembly instruction correspoinding to the reference to the target variable.
• Either:
  • Copy the constant pointer used by the instruction and use it directly. This is the simpler option, but if the game updates the pointer will probably change.
  • Extract a unique signature which can be used to identify this instruction, then use signature scanning to locate it at runtime and extract the pointer. This is more complicated, and will introduce a small amount of overhead during the autosplitter's initialisation, but should be much more resilient to updates.

The gameaction global variable is defined by GZDoom in d_event.h. The type of this variable is gameaction_t, an enum defined as follows:

enum gameaction_t : int
{
	ga_nothing,
	ga_loadlevel,
	ga_newgame,
	ga_newgame2,
	ga_recordgame,
	ga_loadgame,
	ga_loadgamehidecon,
	ga_loadgameplaydemo,
	ga_autoloadgame,
	ga_savegame,
	ga_autosave,
	ga_playdemo,
	ga_completed,
	ga_slideshow,
	ga_worlddone,
	ga_screenshot,
	ga_togglemap,
	ga_fullconsole,
	ga_resumeconversation,
};

The autosplitter uses this variable for auto start functionality by checking when the value is ga_newgame (2).

The level global variable is defined by GZDoom in g_level.cpp. It has type FLevelLocals, a struct which stores information about the active level. FLevelLocals is defined in g_levellocals.h. This is a large struct with many properties, but the one used for the autosplitter is levelnum (offset 0x940). This is a numeric identifer for the current level, which is used by the autosplitter to tell when the player has moved to another level.

NOTE: The autosplitter no longer uses this variable, since level.levelnum fits the use case better.

The nextlevel static variable is defined by GZDoom in g_level.cpp. It has type FString, a string wrapper. When loading a new level, the variable is updated with the name of the level to load. However, the variable is not updated when loading a save game. The autosplitter uses this variable for transition splits.

Below is a mapping from internal map names/numbers to descriptions of those maps:

• TITLE / 0 - Title Screen
• Map01 / 1 - Intro Cutscene
• MAP02 / 2 - Overworld
• MAP03 / 3 - Canyon
• MAP04 / 4 - Lighthouse
• MAP05 / 5 - Observatory
• MAP06 / 6 - Pyramid
• MAP07 / 7 - Volcano
• MAP08 / 8 - Swamp
• MAP09 / 9 - Fish
• MAP10 / 10 - Tundra
• MAP11 / 11 - Nosferatu's Castle
• MAP12 / 12 - End Cutscene
• MAP13 / 13 - Intro Castle