Decompile the Bolt and MBarrier overlays

config/sym_ovl_export.us.txt

@@ -1878,20 +1878,31 @@ func_800B00DC = 0x800b00dc;
 func_800B01B0 = 0x800b01b0;
 func_800B0E7C = 0x800b0e7c;
 MAGIC_Barrier = 0x801b0000;
-BarrierBaseScale = 0x801b0cc0;
-BarrierPrimBuffer = 0x801b0cc4;
-BarrierBufferPtr = 0x801d0cc4;
+barrier_base_scale = 0x801b0cc0;
+barrier_prim_buffer = 0x801b0cc4;
+barrier_buffer_ptr = 0x801d0cc4;
 MAGIC_Brizad = 0x801b037c;
-BrizadRenderDesc = 0x801b1004;
-BrizadPrimBuffer = 0x801b1014;
-BrizadBufferPtr = 0x801d1014;
+g_BrizadRenderDesc = 0x801b1004;
+brizad_prim_buffer = 0x801b1014;
+brizad_buffer_ptr = 0x801d1014;
 MAGIC_Lv5Death = 0x801b0054;
-Lv5DeathTexture = 0x801b05e0;
-Lv5DeathSpriteModel = 0x801c0700;
-Lv5DeathRingModel = 0x801c0868;
-Lv5DeathSpriteDesc = 0x801c0e44;
-Lv5DeathPrimBuffer0 = 0x801c0e50;
-Lv5DeathPrimBuffer1 = 0x801cce50;
-Lv5DeathBufferPtr = 0x801d8e50;
-Lv5DeathFlipEffect = 0x801d8e54;
-Lv5DeathTargetsRemaining = 0x801d8e58;
+g_Lv5DeathTexture = 0x801b05e0;
+g_Lv5DeathSpriteModel = 0x801c0700;
+g_Lv5DeathRingModel = 0x801c0868;
+g_Lv5DeathSpriteDesc = 0x801c0e44;
+g_Lv5DeathPrimBuffer0 = 0x801c0e50;
+g_Lv5DeathPrimBuffer1 = 0x801cce50;
+g_Lv5DeathBufferPtr = 0x801d8e50;
+g_Lv5DeathFlipEffect = 0x801d8e54;
+g_Lv5DeathTargetsRemaining = 0x801d8e58;
+MAGIC_Thunder = 0x801b0000;
+g_ThunderRenderData0 = 0x801b073c;
+g_ThunderRenderData1 = 0x801b07d0;
+g_ThunderModel = 0x801b0898;
+g_ThunderTexture = 0x801b0dac;
+g_ThunderModelMatrix = 0x801c0e2c;
+g_ThunderModelDesc = 0x801c0e4c;
+g_ThunderRenderDesc0 = 0x801c0e5c;
+g_ThunderRenderDesc1 = 0x801c0e68;
+MAGIC_MBarrier = 0x801b0000;
+g_MabariaRenderDesc = 0x801b0c90;

config/symbols.magic-brizad.us.txt

@@ -4,6 +4,4 @@ BrizadAttachToTargetUnused = 0x801B028C;
 BrizadAttachToTarget = 0x801B02D4;
 BrizadDoubleBufferFlip = 0x801B031C;
 MAGIC_Brizad = 0x801B037C;
-BrizadRenderDesc = 0x801B1004; // size:0x10
-BrizadPrimBuffer = 0x801B1014;
-BrizadBufferPtr = 0x801D1014;
+g_BrizadRenderDesc = 0x801B1004; // size:0x10

config/symbols.magic-lv5deth.us.txt

@@ -1,9 +1,9 @@
-Lv5DeathTexture = 0x801B05E0;
-Lv5DeathSpriteModel = 0x801C0700;
-Lv5DeathRingModel = 0x801C0868;
-Lv5DeathSpriteDesc = 0x801C0E44; // size:0xC
-Lv5DeathPrimBuffer0 = 0x801C0E50;
-Lv5DeathPrimBuffer1 = 0x801CCE50;
-Lv5DeathBufferPtr = 0x801D8E50;
-Lv5DeathFlipEffect = 0x801D8E54;
-Lv5DeathTargetsRemaining = 0x801D8E58;
+g_Lv5DeathTexture = 0x801B05E0;
+g_Lv5DeathSpriteModel = 0x801C0700;
+g_Lv5DeathRingModel = 0x801C0868;
+g_Lv5DeathSpriteDesc = 0x801C0E44; // size:0xC
+g_Lv5DeathPrimBuffer0 = 0x801C0E50;
+g_Lv5DeathPrimBuffer1 = 0x801CCE50;
+g_Lv5DeathBufferPtr = 0x801D8E50;
+g_Lv5DeathFlipEffect = 0x801D8E54;
+g_Lv5DeathTargetsRemaining = 0x801D8E58;

config/symbols.magic-mabaria.us.txt

@@ -0,0 +1,9 @@
+MAGIC_MBarrier = 0x801B0000;
+MabariaRenderModel = 0x801B0020;
+MabariaAnimationUpdate = 0x801B01C0;
+MabariaAttachToTarget = 0x801B0378;
+MabariaDoubleBufferFlip = 0x801B04DC;
+MabariaMainSetup = 0x801B053C;
+g_MabariaRenderDesc = 0x801B0C90; // size:0x10
+g_MabariaPrimBuffer = 0x801B0CA8;
+g_MabariaBufferPtr = 0x801D0CA8;

config/symbols.magic-thunder.us.txt

@@ -0,0 +1,16 @@
+MAGIC_Thunder = 0x801B0000;
+ThunderRenderModel = 0x801B0020;
+ThunderSpawnBolt = 0x801B0350;
+ThunderAttachToTarget = 0x801B05A4;
+ThunderDoubleBufferFlip = 0x801B066C;
+ThunderMainSetup = 0x801B06CC;
+g_ThunderRenderData0 = 0x801B073C;
+g_ThunderRenderData1 = 0x801B07D0;
+g_ThunderModel = 0x801B0898;
+g_ThunderTexture = 0x801B0DAC;
+g_ThunderModelMatrix = 0x801C0E2C; // size:0x20
+g_ThunderModelDesc = 0x801C0E4C; // size:0x10
+g_ThunderRenderDesc0 = 0x801C0E5C; // size:0xC
+g_ThunderRenderDesc1 = 0x801C0E68; // size:0xC
+g_ThunderPrimBuffer = 0x801C0E78;
+g_ThunderBufferPtr = 0x801E0E78;

config/us.yaml

@@ -305,3 +305,29 @@ overlays:
     segments:
       - [0, c, lv5deth]
       - [0x5e0, data, lv5deth]
+  # THUNDER.BIN -- "Bolt", the tier-1 lightning spell
+  - name: thunder
+    disk_path: disks/us/MAGIC/THUNDER.BIN
+    sha1: 5767aed5f73876075f01b3958a2e4738fa33b043
+    base_path: magic
+    vram_start: 0x801B0000
+    symbol_addrs_path:
+      - config/sym_export.us.txt
+      - config/symbols.magic-thunder.us.txt
+      - config/sym_export_battle.us.txt
+    segments:
+      - [0, c, thunder]
+      - [0x73c, data, thunder]
+  # MABARIA.BIN -- "MBarrier", the magic-damage half of Wall
+  - name: mabaria
+    disk_path: disks/us/MAGIC/MABARIA.BIN
+    sha1: 9169442d3e1702b7ad4425d95367f52334f84d60
+    base_path: magic
+    vram_start: 0x801B0000
+    symbol_addrs_path:
+      - config/sym_export.us.txt
+      - config/symbols.magic-mabaria.us.txt
+      - config/sym_export_battle.us.txt
+    segments:
+      - [0, c, mabaria]
+      - [0x5b4, data, mabaria]

src/battle/battle.h

@@ -382,14 +382,43 @@ typedef struct {
 
 } Unk800BB75C; // size:0x38
 
+// Flag word at offset 4, as func_800D29D4 tests it. Each mirror bit negates
+// one rotation column, reversing polygon winding, so the cull test XORs their
+// parity back out. Readings agree with Akari's q-gears_reverse
+// (ffvii/DISC/BATTLE/BATTLE.X_model.cpp, "funcd29d4").
+enum ModelRenderFlags {
+    MODEL_MIRROR_X = 0x1,           // negates R11/R21/R31
+    MODEL_MIRROR_Y = 0x2,           // negates R12/R22/R32
+    MODEL_MIRROR_Z = 0x4,           // negates R13/R23/R33
+    MODEL_SEMI_TRANS = 0x8,         // sets bit 1 of the GPU command byte
+    MODEL_NO_DEPTH_CUE = 0x10,      // skips dpcs/dpct under MODEL_DEPTH_CUE
+    MODEL_NO_CULL = 0x20,           // skips nclip; both faces emitted
+    MODEL_PRIM_TPAGE = 0x40,        // tpage from primitive byte 7, not tpage
+    MODEL_DEPTH_CUE = 0x80,         // offset 0xA feeds GTE IR0; see below
+    MODEL_PRIM_PACKET_BITS = 0x100, // primitive byte 7 << 18 ORed into colour
+};
+
+// Model descriptor read by func_800D29D4. Field readings agree with Akari's
+// q-gears_reverse (ffvii/DISC/BATTLE/BATTLE.X_model.cpp, "funcd29d4").
 typedef struct {
-    s32* unk0;
-    s32 unk4;
-    s16 unk8;
-    s16 unkA;
-    s16 unkC;
-    s16 unkE;
-} Unk801B0C98;
+    /* 0x0 */ s32* model;
+    /* 0x4 */ s32 flags;    // ModelRenderFlags
+    /* 0x8 */ u16 uvOffset; // added to every UV halfword; all callers pass 0
+    /* 0xA */ s16 color;    // grey level ORed into the colour word; under
+                            // MODEL_DEPTH_CUE it feeds GTE IR0 instead, so
+                            // 0x1000 blends the model fully into SetFarColor
+    /* 0xC */ s16 tpage;    // packet +0x16; Akari: "blending option"
+    /* 0xE */ s16 clut;     // packet clut halfword
+} ModelRenderDesc;          // size:0x10
+
+// Textured-quad descriptor read by func_800D4D90; ROM instances are packed
+// 0xC apart. Akari: BATTLE.X_units_functions.cpp, "funcd4d90".
+typedef struct {
+    /* 0x0 */ s32* frames;    // per-frame quad blocks, count in each header
+    /* 0x4 */ CVECTOR color;  // packet colour word; cd is 0x2C or 0x2E (POLY_FT4)
+    /* 0x8 */ u16 frameIndex; // blocks skipped; bit 15 enables clutBias
+    /* 0xA */ s16 clutBias;   // added to each quad's clut halfword
+} SpriteRenderDesc;           // size:0xC
 
 typedef struct {
     s16 unk0;
@@ -478,13 +507,19 @@ extern u16 D_8016376A;
 
 int BattleEffectRegister(void (*func)(void));
 void func_800D2980(u_long* addr, s16 imgXY, s16 clutX, s16 clutY);
-void* func_800D29D4(Unk801B0C98*, u_long**, int, void*);
-void func_800D4368(SVECTOR* pos, s32 scale, s32 depthBias);
-void* func_800D4D90(void* desc, u_long** ot, int otLen, void* prim);
+void* func_800D29D4(ModelRenderDesc*, u_long**, int, void*);
+// Build the model matrix for a battle effect: `scale` goes on the matrix
+// diagonal, `pos` is transformed into view space to become the translation,
+// and `depthBias` nudges it along that view vector (negative pulls it toward
+// the camera). Leaves the result installed as the rot/trans matrix.
+MATRIX* func_800D4368(SVECTOR* pos, s32 scale, s32 depthBias);
+void* func_800D4D90(SpriteRenderDesc* desc, u_long** ot, int otLen, void* prim);
 void func_800D5444(int, int, int, void (*func)(int));
+// Returns a scale derived from the target's model size.
+s32 func_800D55A4(s32 target);
 void BattleCommandSend(s32 cmdId, ...);
-int func_800D574C(int);
 void BattleGetPartPosition(s32 arg0, s32 arg1, void* arg2);
+// Runs `func` once per set bit in targetMask, frameStep frames apart.
 void MagicAnimationRegister(s32 targetMask, s32 arg1, s32 frameStep, void (*func)(int));
 s32 BattlePositionToStereoPan(SVECTOR* sv);
 s32 BattleEntityGetStereoPan(s32 arg0);

src/battle/battle1.c

@@ -724,9 +724,9 @@ static void func_800BAFF8(MATRIX* m, VECTOR* v) {
 
 static void func_800BB030(s16 arg0) {
     s32 i;
-    Unk801B0C98* unk;
+    ModelRenderDesc* unk;
 
-    unk = (Unk801B0C98*)0x1F800020;
+    unk = (ModelRenderDesc*)0x1F800020;
     SetFarColor(D_801518E4[arg0].D_8015190C, D_801518E4[arg0].D_8015190D, D_801518E4[arg0].D_8015190E);
     SetRotMatrix(&D_801518E4[arg0].m);
     SetTransMatrix(&D_801518E4[arg0].m);
@@ -738,12 +738,12 @@ static void func_800BB030(s16 arg0) {
         func_800BAF34(&D_800FA6D8[arg0].unk8[i]);
         if (!D_800FA6D8[arg0].unk4[i])
             continue;
-        unk->unk0 = D_800FA6D8[arg0].unk4[i];
-        unk->unk4 = D_800FA6D8[arg0].unk3E[i] | 0x180;
-        unk->unk8 = 0;
-        unk->unkA = D_801518E4[arg0].unk14[0];
-        unk->unkC = 0x20;
-        unk->unkE = D_801518E4[arg0].unk14[1];
+        unk->model = D_800FA6D8[arg0].unk4[i];
+        unk->flags = D_800FA6D8[arg0].unk3E[i] | MODEL_PRIM_PACKET_BITS | MODEL_DEPTH_CUE;
+        unk->uvOffset = 0;
+        unk->color = D_801518E4[arg0].unk14[0];
+        unk->tpage = 0x20;
+        unk->clut = D_801518E4[arg0].unk14[1];
         if (D_801518E4[arg0].D_80151909 & 4) {
             continue;
         }

src/battle/battle2.c

@@ -279,11 +279,14 @@ static void func_800CE638(void) {
     }
 }
 
+// Shell over a covered unit; MBarrier wins when both masks are set. Masks
+// named by Akari's q-gears_reverse (ffvii/address_battle.txt): D_800FA69C is
+// the magic barrier mask, D_80163608 the physical one.
 static void func_800CE75C(void) {
     if ((D_800FA69C >> D_80162978[D_8015169C].D_80162980) & 1) {
-        func_800D67E8(D_80162978[D_8015169C].D_80162980);
+        func_800D67E8(D_80162978[D_8015169C].D_80162980); // MBarrier
     } else if ((D_80163608 >> D_80162978[D_8015169C].D_80162980) & 1) {
-        func_800D67BC(D_80162978[D_8015169C].D_80162980);
+        func_800D67BC(D_80162978[D_8015169C].D_80162980); // Barrier
     }
 }
 
@@ -1268,29 +1271,30 @@ INCLUDE_ASM("asm/us/battle/nonmatchings/battle2", func_800D61AC);
 
 INCLUDE_ASM("asm/us/battle/nonmatchings/battle2", func_800D6260);
 
-extern Unk801B0C98 D_800F14D0;
+extern ModelRenderDesc D_800F14D0;
 
 // Draw a model 4 times through func_800D29D4 (same request-struct pattern as
 // barrier.c's D_801B0C98/D_801B0CB0), toggling the 0x1/0x2 flag bits between
-// passes.
+// passes. Those bits mirror on X and Y, so the four passes are the four
+// quadrants of a symmetric model built from one quarter.
 static void func_800D6394(s32* arg0, s16 arg1) {
-    D_800F14D0.unk0 = arg0;
-    D_800F14D0.unkA = arg1;
+    D_800F14D0.model = arg0;
+    D_800F14D0.color = arg1;
     SetFarColor(0, 0, 0);
     PushMatrix();
     D_80163C74 = func_800D29D4(&D_800F14D0, g_cDb->unk70, 0xC, D_80163C74);
     PopMatrix();
     PushMatrix();
-    D_800F14D0.unk4 |= 1;
+    D_800F14D0.flags |= MODEL_MIRROR_X;
     D_80163C74 = func_800D29D4(&D_800F14D0, g_cDb->unk70, 0xC, D_80163C74);
     PopMatrix();
     PushMatrix();
-    D_800F14D0.unk4 |= 2;
+    D_800F14D0.flags |= MODEL_MIRROR_Y;
     D_80163C74 = func_800D29D4(&D_800F14D0, g_cDb->unk70, 0xC, D_80163C74);
     PopMatrix();
-    D_800F14D0.unk4 &= ~1;
+    D_800F14D0.flags &= ~MODEL_MIRROR_X;
     D_80163C74 = func_800D29D4(&D_800F14D0, g_cDb->unk70, 0xC, D_80163C74);
-    D_800F14D0.unk4 &= ~2;
+    D_800F14D0.flags &= ~MODEL_MIRROR_Y;
 }
 
 INCLUDE_ASM("asm/us/battle/nonmatchings/battle2", func_800D650C);
@@ -1302,20 +1306,19 @@ u8* const D_800A0DC8[] = {D_800F10EC, D_800F11E8, D_800F1304};
 INCLUDE_ASM("asm/us/battle/nonmatchings/battle2", func_800D6734);
 
 void func_800D6734(s32, s32);
-extern s32 D_800F14D4;
 
 static void func_800D67BC(s32 arg0) {
-    D_800F14D4 = 0x88;
+    D_800F14D0.flags = MODEL_DEPTH_CUE | MODEL_SEMI_TRANS; // Barrier
     func_800D6734(arg0, 0);
 }
 
 static void func_800D67E8(s32 arg0) {
-    D_800F14D4 = 0xA8;
+    D_800F14D0.flags = MODEL_DEPTH_CUE | MODEL_NO_CULL | MODEL_SEMI_TRANS; // MBarrier
     func_800D6734(arg0, 1);
 }
 
 void func_800D6814(s32 arg0) {
-    D_800F14D4 = 0x88;
+    D_800F14D0.flags = MODEL_DEPTH_CUE | MODEL_SEMI_TRANS;
     func_800D6734(arg0, 2);
 }