FelineSystem2

An open source remake of the CatSystem2 visual novel engine.

Demo

A makeshift demo of the current version can be found here.

screenshot

Click/Scroll - Advance text

Ctrl/Enter - Advance text, hold to skip

SPACE - Hide message window

f - Toggle fullscreen

1-9 - Select choice

Shift + Alt + 1-9 - Quick save to slot 1-9

Shift + 1-9 - Quick load from slot 1-9

FelineSystem2 implements a custom database of the game's KIF archives and assets, stored as a binary file.

Data Type	Value	Description
`char[len]`	ArchiveName	NULL-terminated filename of the KIF archive
`uint32`	EntryCount	Number of entries in archive
`unsigned char`	IsEncrypted	`0x01` if archive is encrypted, `0x00` otherwise
`byte[4]`	FileKey	Blowfish key for decrypting entries (Only exists if IsEncrypted is `0x01`)
`0x00`	TableEnd	Signifies end of table

Data Type	Value	Description
`char[len]`	FileName	NULL-terminated deobfuscated filename
`uint32`	Offset	The offset to the entry's data
`uint32`	Length	The length of the entry's data

If statements must contain a whitespace after the closing parenthesis of the condition
- if (#300==0) #(950+#300)=512
Operators follow C-Style left-to-right precedence and associativity
Integers and strings are the only data types that exist
- #300=0
- str 50 bg02
Variable names can only be integers
Variable names can be dynamically evaluated
- #(950+#300)=512

blend argument specifies the alpha value that the image will be displayed at
- cg 0 blend 255 will display a completely opaque CG while cg 0 blend 0 will display a completely transparent CG
rdraw command after an image specifies the duration to fade to the target opacity
- rdraw 30 will take 30 frames to fade the image from alpha 0 to the target alpha (e.g. 255 by default)
- Units are likely in frames at 60fps (0.0167s/frame) regardless of the game's refresh rate setting
- An rdraw command will apply to all images within a script block (from a user input to the next wait command)
wait command without arguments will block until any time-based command completes
- wait after a rdraw 30 command will wait for the 30 frames taken to completely fade in the images before proceeding to the next command
wait with arguments behaves differently from standalone wait
- wait 60 will block for 60 frames before proceeding to the next command
- wait 60 will not be aware of any time-based commands like rdraw and will not block until rdraw completes
- wait is sometimes used along with wait 60 consecutively
cg 0 attr 1 (70+0) (80+0)
cg 0 attr 2 (75+0) (85+0)
- Assigns the BaseX, BaseY values of the specified image cg 0 to the variables #(75+0) and #(85+0) respectively

Trigger for creating such an amazingly comprehensive knowledgebase of the CS2 engine
asmodean for being a pioneer in reversing the CS2 engine
Dodder for Hacking the Grisaia for localization
koestl for his impeccable translations and contributions to localization