PATCHES: Keen 3 sprite behaviour

[levellord]

Each of the sprites in Keen 3 calls a specific function to dictat its behaviour. Functions of interest are:

$00 Sprite doesn't appear
$01 Sprite kills foobs only [Used by Keen]
$02 Sprite kills keen only [Used by vorticons]
$03 Sprite stuns Keen [Used by vortikids]
$04 Sprite harmless (even to foobs) [used by vortimoms]
$05 Sprite pushes Keen [Used by Meeps]
$06 Sprite kills keen [used by vortninjas]
$07 Sprite doesn't kill foobs or Keen [Used by Foobs]
$08 Keen can stand on sprite [Used by horizontal platforms]
$09 Kills [Used by spike ball]
$0A Like $08 [Used by vertical platforms, use on jumping enemies]
$0B Kills [Not used by anything]
$0C Doesn't do anything [used by purple sparks]
$0D Ditto [used by beating heart]
$0E Uber ditto [Used by something]
$0F Keens bullet [Kills sprites, not Keen]
$10 Kills Keen and sprites [vortimom shot]
$11 Meep bullet behaviour [Kills Keen]

These are found at the following locations:

Vorticons:
%patch $3C2B $02 $00
Vortikids:
%patch $3C8D $03 $00
Vortimoms:
%patch $3CEF $04 $00
Meeps:
%patch $3D51 $05 $00
Vortninjas:
%patch $3DB9 $06 $00
Foobs:
%patch $3E1B $07 $00
Horizontal platforms:
%patch $3E7D $08 $00
Spikeball:
%patch $3EFF $09 $00
Red ball:
%patch $3F81 $0A $00
Vertical platforms:
%patch $3FC9 $0A $00


This allows of course, numerous pathces, which, because I am evil, I will list here:

Code: Select all

###
#Vorticons
###

#Vorticon don't appear [use as easy med hard patch- easy]
%patch $3C2B $00 $00

#Vorticon kill foobs but not Keen
%patch $3C2B $01 $00
#Like above but don't kill foobs
%patch $3C2B $07 $00

#Vorticon kill Keen if touched
%patch $3C2B $02 $00

#Vorticon stun Keen
%patch $3C2B $03 $00

#Vorticon push keen around
%patch $3C2B $05 $00

#Vorticon carry Keen
%patch $3C2B $08 $00

#Vorticon strength
%patch $3C58 $01 $00 


###
#Vortikids
###

#Vortikids don't appear [use as easy med hard patch- easy]
%patch $3C8D $00 $00

#Vortikids kill foobs but not Keen
%patch $3C8D $01 $00
#Like above but don't kill foobs
%patch $3C8D $07 $00

#Vortikids kill Keen if touched
%patch $3C8D $02 $00

#Vortikids stun Keen
%patch $3C8D $03 $00

#Vortikids push keen around
%patch $3C8D $05 $00

#Vortikids carry Keen
%patch $3C8D $08 $00


###
#Vortimoms
###

#Vortimoms don't appear [use as easy med hard patch- easy]
%patch $3CEF $00 $00

#Vortimoms kill foobs but not Keen, can't shoot.
%patch $3CEF $01 $00
#Like above but don't kill foobs
%patch $3CEF $07 $00

#Vortimoms kill Keen, can't shoot.
%patch $3CEF $02 $00

#Vortimoms stun Keen, can't shoot.
%patch $3CEF $03 $00

#Vortimoms push keen around, non lethal, can't shoot
%patch $3CEF $05 $00

#Vortimoms carry Keen, can't shoot.
%patch $3CEF $08 $00

# Vortimom strength
%patch $3D1C $05 $00 


###
#Meeps
###

#Meeps don't appear [use as easy med hard patch- easy]
%patch $3D51 $00 $00

#Meeps kill foobs but not Keen
%patch $3D51 $01 $00
#Like above but don't kill foobs
%patch $3D51 $07 $00

#Meeps kill Keen if touched
%patch $3D51 $02 $00

#Meeps stun Keen
%patch $3D51 $03 $00

#Meeps push keen around
%patch $3D51 $05 $00

#Meeps carry Keen
%patch $3D51 $08 $00

#Meep strength 
%patch $3D84 $04 $00


###
#Vortninjas
###

#Vortninjas don't appear [use as easy med hard patch- easy]
%patch $3DB9 $00 $00

#Vortninjas kill foobs but not Keen
%patch $3DB9 $01 $00
#Like above but don't kill foobs
%patch $3DB9 $07 $00

#Vortninjas stun Keen
%patch $3DB9 $03 $00

#Vortninjas push keen around
%patch $3DB9 $05 $00

#Vortninjas carry Keen
%patch $3DB9 $08 $00

#Vortininja strength
%patch $3DE6 $05 $00 


###
#Foobs
###

#Foobs don't appear [use as easy med hard patch- easy]
%patch $3E1B $00 $00

#Foobs kill other foobs but not Keen
%patch $3E1B $01 $00
#Like above but don't kill foobs
%patch $3E1B $07 $00

# Make foob kill Keen if touched. 
%patch $3E1B $02 $00

#Foobs stun Keen, can't shoot.
%patch $3E1B $03 $00

#Foobs push keen around
%patch $3E1B $05 $00

#Foobs carry Keen
%patch $3E1B $08 $00

[MultiMania]

Lots of very good work. The code hasn't even whimpered. (Yet)

[KeenRush]

This is neat! Finally someone dig up those values.. :) Definitely going to use some of them in my Keen 3 mod. In case this topic wouldn't exist at the time I need these in future, I would've needed to search for them by myself. Glad I don't need to. :)

By the way, does something else affect to foobs than shots by other enemies? They can't step on them, right?

[KeenRush]

Well, if you could add there description for "$0C", it seems to miss it.

And, if you have time, you could search for the values that 'spawn dead vorticon when die' etc. :)

[levellord]

By the way, does something else affect to foobs than shots by other enemies? They can't step on them, right?

Yes, Keen touching them.

And, if you have time, you could search for the values that 'spawn dead vorticon when die' etc. :)

Hmmm, sorry, no sprite spawn. As payment for my faliure, I present these humble offerings and beg your forgiveness:

##
#Sprite behaviours and locations
##

Code: Select all

#Vorticon behaviour
%patch $3C4E $4A $41

#Vortikid behaviour
%patch $3CB0 $11 $43

#Vortimoms
%patch $3D12 $0C $44

#Meep behaviour:
%patch $3D7A $46 $47

#Vortninja behaviour
%patch $3DDC $F7 $48

#Foob behaviour:
%patch $3E3E $0C $4A

#Ball behaviour
%patch $3EA0 $0B $4C

#Jack behaviour
%patch $3F22 $BD $4B

#Horizontal platform behaviour
%patch $3FAA $47 $4C

#Vertical platform behaviour [Same as horizontal, to be vert needs
#Special code at sprite speed area]
%patch $3FEC $47 $4C

#Purple spark behaviour
%patch $4094 $02 $4E

#Heart behaviour
%patch $40D1 $A6 $4E

#Heart behaviour
%patch $40D1 $A6 $4E

#Unknown behaviour, makes a Keen that runs right across screen then zots.
%patch $456D $6E $46

#Unknown behaviour 2, keen runs slowly left across screen [while facing right] 
#behaves like sprite when hits Keen
%patch $4877 $D2 $48

#Rightward bullet behaviour When changed, sprite appears after pause, i.e making
#it the vorticon sprite makes the bullet spawn a vorticon at every shot, like
#the ice cannons shooting yorps
%patch $4D8C $F2 $4C

#Downward bullet behaviour, see above for changing
#Same as horizontal, needs code near speed to make it vertical [See vert plat]
%patch $4DF3 $F2 $4C

#Unknown behaviour 3, nonanimatinging sprite moves left, simalar to UB 2
%patch $7D07 $29 $7E

To make one sprite behave like another, just change the behaviour value e.g:

#The bullet sprite spawns vortikids
%patch $4D8C $11 $43

[levellord]

Figured out all the sprite behaviours [mostly] More patches must follow!