Arc Range Calculation Routine
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Computes and marks the tiles within range of a longbow attack.
Iterates through all tiles on the map.
- If the tile is within 3 squares of the caster, skip.
- Calculate the height effect on range:
[(casterHeight - tileHeight)/4]. - Checks effective distance + height effect against weapon range.
- Marks tiles within effective range.
Calculate Arc Range r4 = Caster Data r5 = Weapon Range
001798b0: 27bdffd0 addiu r29,r29,0xffd0 001798b4: afb00020 sw r16,0x0020(r29) 001798b8: 00808021 addu r16,r4,r0 r16 = Caster Data 001798bc: afb10024 sw r17,0x0024(r29) 001798c0: afbf0028 sw r31,0x0028(r29) 001798c4: 0c05e5ed jal 0x001797b4 Height vs Water and Float Routine 001798c8: 00a08821 addu r17,r5,r0 r17 = Weapon Range 001798cc: 00401821 addu r3,r2,r0 r3 = Height Value/Depth (Return) 001798d0: 920c0047 lbu r12,0x0047(r16) r12 = Caster X 001798d4: 3c02800e lui r2,0x800e 001798d8: 90424ea0 lbu r2,0x4ea0(r2) r2 = Max Map Y 001798dc: 920d0048 lbu r13,0x0048(r16) r13 = Caster Y 001798e0: 18400049 blez r2,0x00179a08 Exit if Max Y is negative 001798e4: 00004821 addu r9,r0,r0 r9 = Y Counter 001798e8: 3c108019 lui r16,0x8019 001798ec: 2610f8cc addiu r16,r16,0xf8cc r16 = Tile Data Array (18f8cc) 001798f0: 306e00ff andi r14,r3,0x00ff r14 = CasterHeight2 (Caster's effective height, times 2) 001798f4: 322500ff andi r5,r17,0x00ff r5 = Weapon Range 001798f8: 340f0001 ori r15,r0,0x0001 r15 = 0x0001 001798fc: 01a9102a slt r2,r13,r9 If Caster Y < Y Counter 00179900: 14400002 bne r2,r0,0x0017990c Branch if True 00179904: 012d5823 subu r11,r9,r13 r11 = Y Counter - Caster Y 00179908: 01a95823 subu r11,r13,r9 r11 = Caster Y - Y Counter 0017990c: 3c02800e lui r2,0x800e 00179910: 90424e9c lbu r2,0x4e9c(r2) r2 = Max Map X 00179914: 00000000 nop 00179918: 18400035 blez r2,0x001799f0 Branch if Max X is negative 0017991c: 00004021 addu r8,r0,r0 r8 = X Counter 00179920: 0188102a slt r2,r12,r8 If Caster X < X Counter 00179924: 14400002 bne r2,r0,0x00179930 Branch if true 00179928: 010c1023 subu r2,r8,r12 r2 = X Counter - Caster X 0017992c: 01881023 subu r2,r12,r8 r2 = Caster X - Counter X 00179930: 004b5021 addu r10,r2,r11 r10 = 2D Distance to Current Position 00179934: 29420003 slti r2,r10,0x0003 If Distance < 3 (within min range) 00179938: 14400027 bne r2,r0,0x001799d8 Branch if True (skip this XY position) 0017993c: 00000000 nop 00179940: 00003821 addu r7,r0,r0 r7 = Level Counter 00179944: 3c02800e lui r2,0x800e 00179948: 90424e9c lbu r2,0x4e9c(r2) r2 = Max Map X 0017994c: 00000000 nop 00179950: 01220018 mult r9,r2 Y Counter * Max X 00179954: 00071a00 sll r3,r7,0x08 00179958: 00001012 mflo r2 0017995c: 00621821 addu r3,r3,r2 Y Counter * Max X + Level Counter 00179960: 00683021 addu r6,r3,r8 r6 = Y Counter * Max X + Level Counter + X Counter 00179964: 000610c0 sll r2,r6,0x03 00179968: 00501021 addu r2,r2,r16 r2 = Current Tile Data 0017996c: 90430002 lbu r3,0x0002(r2) Current Tile's Height (int part) 00179970: 90440003 lbu r4,0x0003(r2) Current Tile's Height (halves and depth) 00179974: 90420003 lbu r2,0x0003(r2) Current Tile's Height (halves and depth) 00179978: 00031840 sll r3,r3,0x01 0017997c: 3084001f andi r4,r4,0x001f r4 = Height(halves) 00179980: 00641821 addu r3,r3,r4 r3 = Height*2 + Height(halves) 00179984: 00021142 srl r2,r2,0x05 r2 = Height(depth) 00179988: 00021040 sll r2,r2,0x01 r2 = Height(depth) * 2 0017998c: 00621821 addu r3,r3,r2 r3 = Height*2 + Halves + Depth*2 00179990: 306300ff andi r3,r3,0x00ff Cast to unsigned byte 00179994: 01c31023 subu r2,r14,r3 r2 = Caster Height*2 - Tile Height*2 00179998: 04410002 bgez r2,0x001799a4 If r2 is negative: 0017999c: 00000000 nop 001799a0: 24420003 addiu r2,r2,0x0003 > r2 += 0x0003 (causes negatives to round up) 001799a4: 00021083 sra r2,r2,0x02 r2 = trunc(r2 / 4) (height effect on range) 001799a8: 01421023 subu r2,r10,r2 r2 = Distance - HeightEffect 001799ac: 00a2102a slt r2,r5,r2 If Weapon Range < Distance - HeightEffect 001799b0: 14400006 bne r2,r0,0x001799cc Branch if True (Effective distance is still too high.) 001799b4: 24e70001 addiu r7,r7,0x0001 Level Counter++ 001799b8: 00061080 sll r2,r6,0x02 001799bc: 00461021 addu r2,r2,r6 r2 = Current Tile Index 001799c0: 3c018019 lui r1,0x8019 001799c4: 00220821 addu r1,r1,r2 001799c8: a02f2dd8 sb r15,0x2dd8(r1) AoE = 1 to Current Tile (Tile is part of Range) 001799cc: 28e20002 slti r2,r7,0x0002 If Level Counter < 2 001799d0: 1440ffdc bne r2,r0,0x00179944 Loop if True (Repeat for High Tile) 001799d4: 00000000 nop 001799d8: 3c02800e lui r2,0x800e 001799dc: 90424e9c lbu r2,0x4e9c(r2) r2 = Max Map X 001799e0: 25080001 addiu r8,r8,0x0001 X Counter++ 001799e4: 0102102a slt r2,r8,r2 If X Counter < Max X 001799e8: 1440ffce bne r2,r0,0x00179924 Loop if True 001799ec: 0188102a slt r2,r12,r8 If Caster X < X Counter 001799f0: 3c02800e lui r2,0x800e 001799f4: 90424ea0 lbu r2,0x4ea0(r2) r2 = Max Map Y 001799f8: 25290001 addiu r9,r9,0x0001 Y Counter++ 001799fc: 0122102a slt r2,r9,r2 If Y Counter < Max Y 00179a00: 1440ffbf bne r2,r0,0x00179900 Loop if True 00179a04: 01a9102a slt r2,r13,r9 If Caster Y < Y Counter 00179a08: 8fbf0028 lw r31,0x0028(r29) 00179a0c: 8fb10024 lw r17,0x0024(r29) 00179a10: 8fb00020 lw r16,0x0020(r29) 00179a14: 27bd0030 addiu r29,r29,0x0030 00179a18: 03e00008 jr r31 00179a1c: 00000000 nop
