From a2c40122fe148812850428526721cefd0542bec6 Mon Sep 17 00:00:00 2001
From: Aleksandr Shabelnikov <mistermidi@gmail.com>
Date: Thu, 5 Dec 2024 12:01:51 +0100
Subject: [PATCH] `tt_003` func_us_801771B0 decompile (#1972)

Big shout to @Onenutmcgee for figuring out that hitboxOffX seems to be
s16 for Servants overlays.
---
 include/game.h             |   2 +-
 include/servant.h          |   1 +
 src/servant/tt_003/demon.c | 127 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 128 insertions(+), 2 deletions(-)

diff --git a/include/game.h b/include/game.h
index 7ee9d0b8af..a0298b88df 100644
--- a/include/game.h
+++ b/include/game.h
@@ -798,7 +798,7 @@ typedef struct Entity {
     /* 0x04 */ f32 posY;
     /* 0x08 */ s32 velocityX;
     /* 0x0C */ s32 velocityY;
-#if defined(STAGE) || defined(WEAPON)
+#if defined(STAGE) || defined(WEAPON) || defined(SERVANT)
     /* 0x10 */ s16 hitboxOffX;
 #else // hack to match in DRA and RIC
     /* 0x10 */ u16 hitboxOffX;
diff --git a/include/servant.h b/include/servant.h
index 8c8d936d10..5bd546c677 100644
--- a/include/servant.h
+++ b/include/servant.h
@@ -1,5 +1,6 @@
 #ifndef SERVANT_H
 #define SERVANT_H
+#define SERVANT
 #include <common.h>
 #include <game.h>
 
diff --git a/src/servant/tt_003/demon.c b/src/servant/tt_003/demon.c
index fc9eca162e..57c08dc681 100644
--- a/src/servant/tt_003/demon.c
+++ b/src/servant/tt_003/demon.c
@@ -1826,7 +1826,132 @@ void func_us_80176C1C(Entity* self) {
     }
 }
 
-INCLUDE_ASM("servant/tt_003/nonmatchings/demon", func_us_801771B0);
+// PSX: https://decomp.me/scratch/qDGTj
+// PSP: https://decomp.me/scratch/D67x7
+
+extern s32 D_us_80178688;
+extern s32 D_us_8017868C;
+extern s16 D_us_80171B44[3][8];
+
+void func_us_801771B0(Entity* self) {
+    Primitive* prim;
+    s16 colorValue;
+    s32 i;
+    // s32 i;
+    s32 posX_hi;
+    s32 posY_hi;
+    s16* uvCoords;
+
+    switch (self->step) {
+    case 0:
+        if (self->params == 0) {
+            D_us_80178688 = self->posX.val;
+            D_us_8017868C = self->posY.val;
+        } else {
+            self->posX.val = D_us_80178688;
+            self->posY.val = D_us_8017868C;
+        }
+
+        self->primIndex = g_api.AllocPrimitives(PRIM_GT4, 3);
+        if (self->primIndex == -1) {
+            DestroyEntity(self);
+            return;
+        }
+
+        self->flags =
+            FLAG_POS_CAMERA_LOCKED | FLAG_KEEP_ALIVE_OFFCAMERA | FLAG_HAS_PRIMS;
+        HIH(self->velocityX) = (self->facingLeft != 0) ? -0x10 : 0x10;
+
+        switch (self->params) {
+        case 2:
+            self->posY.i.hi += 8;
+        case 1:
+            self->posY.i.hi += 8;
+        case 0:
+            self->posX.i.hi += (self->facingLeft != 0) ? -0x20 : 0x20;
+        }
+
+        prim = &g_PrimBuf[self->primIndex];
+        for (i = 0; i < 3; i++) {
+            prim->tpage = 0x1A;
+            prim->clut = 0x147;
+            prim->priority = self->zPriority + 1;
+            prim->drawMode =
+                DRAW_TPAGE2 | DRAW_TPAGE | DRAW_COLORS | DRAW_TRANSP;
+            prim->u0 = prim->u2 = 0xB;
+            prim->u1 = prim->u3 = 0x35;
+            prim->v0 = prim->v1 = 0xCB;
+            prim->v2 = prim->v3 = 0xF5;
+            PCOL(prim) = 0x80;
+
+            prim = prim->next;
+        }
+
+        g_api.GetServantStats(self, 0x1B, 1, &s_DemonStats);
+
+        self->hitboxOffX = -4;
+        self->hitboxOffY = 0;
+        self->hitboxWidth = 0x1C;
+        self->hitboxHeight = 4;
+
+        self->step++;
+        if (self->params >= 2) {
+            self->step++;
+        }
+        break;
+
+    case 1:
+        self->ext.et_801737F0.animationTriggerCount += 1;
+        self->posX.val += self->velocityX;
+
+        if (self->ext.et_801737F0.animationTriggerCount >= 3) {
+            CreateEventEntity(self, 0xDE, self->params + 1);
+            self->step += 1;
+        }
+        break;
+
+    case 2:
+        self->posX.val += self->velocityX;
+        self->ext.et_801737F0.animationTriggerCount += 1;
+
+        if ((u16)(self->posX.i.hi + 0x20) > 0x140) {
+            DestroyEntity(self);
+            return;
+        }
+        break;
+    }
+
+    posX_hi = self->posX.i.hi;
+    posY_hi = self->posY.i.hi;
+
+    prim = &g_PrimBuf[self->primIndex];
+    for (i = 0; i < 3; i++) {
+
+        if (self->facingLeft) {
+            prim->x0 = posX_hi - D_us_80171B44[i][0];
+            prim->y0 = posY_hi - D_us_80171B44[i][1];
+            prim->x1 = posX_hi - D_us_80171B44[i][2];
+            prim->y1 = posY_hi - D_us_80171B44[i][3];
+            prim->x2 = posX_hi - D_us_80171B44[i][4];
+            prim->y2 = posY_hi - D_us_80171B44[i][5];
+            prim->x3 = posX_hi - D_us_80171B44[i][6];
+            prim->y3 = posY_hi - D_us_80171B44[i][7];
+        } else {
+            prim->x0 = posX_hi + D_us_80171B44[i][0];
+            prim->y0 = posY_hi + D_us_80171B44[i][1];
+            prim->x1 = posX_hi + D_us_80171B44[i][2];
+            prim->y1 = posY_hi + D_us_80171B44[i][3];
+            prim->x2 = posX_hi + D_us_80171B44[i][4];
+            prim->y2 = posY_hi + D_us_80171B44[i][5];
+            prim->x3 = posX_hi + D_us_80171B44[i][6];
+            prim->y3 = posY_hi + D_us_80171B44[i][7];
+        }
+
+        PCOL(prim) =
+            ((self->ext.et_801737F0.animationTriggerCount & 1) * 64) + 0x40;
+        prim = prim->next;
+    }
+}
 
 extern s32 D_us_801786D0;
 extern s32 D_us_801786D4;