Check if Unit can be Targeted

Parameters : r5 = previous routine stack pointer
             r4 = Unit ID
Returns : r2 = 0x01 if unit cannot be targeted
          r2 = 0x00 if unit can be target (Exist, not crystal, not jumping, not treasure, not ridden)
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0017bdd0: 27bdffe0 addiu r29,r29,0xffe0     |
0017bdd4: afb00010 sw r16,0x0010(r29)       |
0017bdd8: 00a08021 addu r16,r5,r0           |r16 = Stack Pointer (previous routine)
0017bddc: 000410c0 sll r2,r4,0x03           |r2 =Unit ID * 8
0017bde0: 00441023 subu r2,r2,r4            |r2 =Unit ID * 7
0017bde4: 00021180 sll r2,r2,0x06           |r2 =Unit ID * 448 (0x1c0)
0017bde8: 3c038019 lui r3,0x8019            |
0017bdec: 246308cc addiu r3,r3,0x08cc       |r3 = 0x801908cc (start of unit 0x00 data)
0017bdf0: afb10014 sw r17,0x0014(r29)       |
0017bdf4: 00438821 addu r17,r2,r3           |r17 = Unit's Data Pointer
0017bdf8: afbf0018 sw r31,0x0018(r29)       |
0017bdfc: 0c060428 jal 0x001810a0           |-->Map Location Calculation  return r2 = Unit Tile Info ( X coord.  +( Y coord. * Map Max X) + elevation * 256 (= 0x00 or 0x100)
0017be00: 02202021 addu r4,r17,r0           |r4 = Unit's Data Pointer
0017be04: ae020000 sw r2,0x0000(r16)        |Store Tile ID in stack pointer  (previous routine)
0017be08: 92230001 lbu r3,0x0001(r17)       |r3 = Unit ID
0017be0c: 340200ff ori r2,r0,0x00ff         |r2 = 0xff
0017be10: 1062000f beq r3,r2,0x0017be50     #If unit exists / Else branch to End With r2 = 0x01
0017be14: 34020001 ori r2,r0,0x0001         |r2 = 0x01
0017be18: 92220058 lbu r2,0x0058(r17)            |r2 = Unit's Current Statuses 1
0017be1c: 00000000 nop                           |
0017be20: 30420044 andi r2,r2,0x0044             |r2 <> 0x00 if unit has crystal or jump
0017be24: 1440000a bne r2,r0,0x0017be50          #If unit doesn't have crystal or jump / Else branch to End With r2 = 0x01
0017be28: 34020001 ori r2,r0,0x0001              |r2 = 0x01
0017be2c: 92220059 lbu r2,0x0059(r17)                |r2 = Unit's Current Statuses 2
0017be30: 00000000 nop                               |
0017be34: 30420001 andi r2,r2,0x0001                 |r2 = 0x01 if unit has treasure
0017be38: 14400005 bne r2,r0,0x0017be50              #If unit doesn't has treasure / Else branch to End With r2 = 0x01
0017be3c: 34020001 ori r2,r0,0x0001                  |r2 = 0x01
0017be40: 92220182 lbu r2,0x0182(r17)                    |r2 =  Unit's Mount Info
0017be44: 00000000 nop                                   |
0017be48: 30420040 andi r2,r2,0x0040                     |r2 = 0x40 if unit is being ridden / Else 0x00
0017be4c: 0002102b sltu r2,r0,r2                         |r2 = 0x01 if Unit is being Ridden / Else 0x00
0017be50: 8fbf0018 lw r31,0x0018(r29)        END
0017be54: 8fb10014 lw r17,0x0014(r29)                    
0017be58: 8fb00010 lw r16,0x0010(r29)                    
0017be5c: 27bd0020 addiu r29,r29,0x0020                  
0017be60: 03e00008 jr r31                                
0017be64: 00000000 nop 

Return locations

0017bce4: Check_Allies/Enemies_that_can_be_Targeted                              
0017cba8: Reaction_Target/Hit_Calculation