Obj Mure
From CloudModding OoT Wiki
ovl_Obj_Mure is the actor used to spawn a group of bugs, butterflies, or fish.
NTSC 1.0 Notes
Instance Variables
| Offset | Type | Description |
|---|---|---|
| 0x0140 | short | Number of actors spawned |
| 0x0142 | short | Table lookup for number of actors to spawn. Valid range 0-3. Lookup only occurs if above <= 0 |
| 0x0144 | short | Unknown. Changes spawn function used. |
| 0x0146 | short | Type of actor to spawn. 02 = Fish, 03 = Bugs, 04 = Butterflies |
| 0x0148 | actor ptr[15] | Points to the actors spawned |
| 0x0184 | byte[15] | Unknown, related to above |
Asm Notes
1E8200 - Actor File
1E9240 - Actor Instance
&F000, 0x0140 = Spawn Count
&0700, 0x0142 = Spawn Count Lookup Table
&0060, 0x0144 = ?
&001F, 0x0146 = Type
828C LH V0, 0x001C(A0) //load variable component
8290 SRA T8, V0, 0x8
8294 ANDI T9, T8, 0x0007 //Store in T9 ? (&0700)
8298 SH T9, 0x0142(A0) //Save (&0700)
829C LH T3, 0x0142(A0)
82A0 SRA T6, V0, 0xC
82A4 SRA T0, V0, 0x5
82A8 ANDI T7, T6, 0x000F //Store in T7 ? (&F000)
82AC ANDI T1, T0, 0x0003 //Store in T1 ? (&0060)
82B0 ANDI T2, V0, 0x001F //Store in T2 Type? (&001F)
82B4 SLTI AT, T3, 0x0004 //is (&0700) < 4?
82B8 SH T7, 0x0140(A0) //Save (&F000)
82BC SH T1, 0x0144(A0) //Save (&0060)
82C0 BNEZ AT, 801E82D8 //Jump if (&0700) < 4
82C4 SH T2, 0x0146(A0) //Save (&001F)
82C8 JAL 80020EB4
82D8 LH T4, 0x0146(A0)//load (&001F)
82DC SLTI AT, T4, 0x0005 //is (&001F) < 5?
82E0 BNEZ AT, 801E82F8
82F8 JAL 801E8258 //-> JAL 801E8200
82FC SW A0, 0x0018(SP)
{
820C LH V0, 0x0146 //load (&001F)
8214 LUI A1, 0x801F
//From here, checks if V0 (&001F) is 2, 3, 4, and goes to 1E8230 if so (below),
//else jumps to 1E8240 which zeros V0. Both sync at 1E8248, with V0 being 1 if
//the program goes to 1E8230
8230 JAL 80063F7C
8234 ADDIU A1, A1, 0x908C // A1 = 801E908C
8238 BEQ R0, R0, 801E8248
823C ADDIU V0, R0, 0x0001
8248 LW RA, 0x0014(SP)
8250 JR RA
//if V0 is only 1 or 0, these instructions are useless (aside from setting RA)
8268 BNEZ V0, 801E8278 // (branch if (&001F) is 2-4)
826C LW RA, 0x0014(SP)
827C JR RA
}
8300 BNEZ V0, 801E8318 // (branch if (&001F) is 2-4)
8304 LW A0, 0x0018(SP)
8308 JAL 80020EB4
8318 LUI T5, 0x801F
831C ADDIU T5, T5, 0x88D8 //T5 = 801E88D8
8320 SW T5, 0x013C(A0) //Store T5 at 0x013C from instance start
--- (&0060) ---
//(&001F) = 4 in case it matters
86B4 LH V0, 0x0144(A0)
86B8 ADDIU AT, R0, 0x0001 //AT = 1
86BC BEQ V0, R0, 0x801E86D4 //V0 = 0? goto JAL 801E8398, then returns from function
86C4 BEQ V0, AT, 0x801E86E4 //V0 = 1? goto JAL 801E8560, then returns from function
86CC BEQ R0, R0, 0x801E86F0 //return from function
## Function 801E8560 ##
//Spawns V0 number of actors
//pushes variables on the stack
8594 JAL 801E8344
//V0 contains number of things to spawn
859C OR S5, V0, R0
85A0 BLEZ V0, 801E867C //Jumps to the function's end
85A4 OR S1, R0, R0 //S1 = 0 (set spawned actor count 0)
85A8 ADDIU S6, S4, 0x1C24 //S4 = 801C84A0 (game_play), S6 = 801CA0C4
85AC OR S2, S0, R0 //S0 = instance location
85B0 OR S3, S0, R0 //S0 = instance location
85B4 ADDIU S7, S0, 0x0024 //offset to x,y,z coord
85B8 ADDIU S8, SP, 0x007C
85BC OR A0, S8, R0
85C0 OR A1, S7, R0 //A1 = offset to x,y,z coord
85C4 LH A2, 0x0142(S0) // &0700 var
85C8 JAL 801E8370 //Pushes (&0700) var, spawn count, and x,y,z on stack without moving sp
85CC OR A3, S1, R0 //A3 = 0?
85D0 LH V0, 0x0146(S0) //V0 = (&001F) var
85D4 ADDIU AT, R0, 0x0004 //AT = butterfly
85D8 OR A0, S6, R0 //A0 = 801CA0C4
85DC BNE V0, AT, 801E85F4 //branch if type != butterfly
85E0 LWC1 F4, 0x0080(SP)//F4 = Y as float
85E4 BNEZ S1, 801E85F4
84E8 ADDIU T0, R0, 0x0001
85EC BEQ R0, R0, 801E8604
85F0 SLL V1, V0, 0x1
8604 LWC1 F6, 0x0084(SP)//F6 = Z as float
8608 SWC1 F4, 0x0010(SP)
860C LUI A2, 0x801F
8610 SWC1 F6, 0x0014(SP)
8614 LH T6, 0x0030(S0)
8618 ADDIU A2, A2, V1
861C LH A2, 0x9074 //gets actor id from 1E9074 + Type * 2
8620 SW T6, 0x0018(SP)
8624 LH T7, 0x0032(S0)
8628 OR A1, S4, R0 //A1 = Game Play
862C LW A3, 0x007C(SP)//A3 = X as float
8630 SW T7, 0x001C(SP)
863C JAL 80025110 //call spawn actor function
8640 SW T8, 0x0020(SP)
8644 BEQ V0, R0, 801E8660 //jump if the spawn function failed to create an actor
8648 SW V0, 0x0148(S2) //store spawned actor pointer at 0x0148 into instance
864C SB R0, 0x0184(S3) //store 0 at 0x0184 into instance
8650 LW T1, 0x0148(S2)
8654 LB T9, 0x0003(S0) //load binding room index
8658 BEQ R0, R0, 801E8668
865C SB T9, 0x0003(T1) //Set spawned actor's current room to this actor's room
8668 ADDIU S1, S1, 0x0001 //Number of actors spawned += 1
866C SLT AT, S1, S5 //AT = 1 if number of spawned actors is less than total being spawned
8670 ADDIU S2, S2, 0x0004 //Increment S2 by 4 (array at 0x0148)
8674 BNEZ AT, 801E85BC //loop
8678 ADDIU S3, S3, 0x0001 //increment S3 by 1 (array at 0x0184)
#######################
## Function 801E8344 ##
//determines whether to use the spawn count, or look up a pre-defined spawn count
8344 LH V1, 0x0140(A0) //load (&F000)
8348 BNEZ V1, 801E8368
834C OR V0, V1, R0 //V0 = (&F000)
//(&F000 is 0)
8350 LH T6, 0x0142(A0) //load (&0700)
//basically performs a table lookup for the number of things to spawn
//the table is located at 801E9064
//Then returns to caller
8368 JR RA
#######################
## Function 801E8370 ##
//Pushes (&0700) var, spawn count, and x,y,z on stack without moving sp
//A0 = Stack Pointer + 7C
//A1 = Coordinates pointer
//A2 = (&0700) var
//A3 = ?