1 files changed, 25 insertions, 12 deletions

diff --git a/src/battle/anim/bug.c b/src/battle/anim/bug.c
index e12f55a8b..d57a1046e 100644
--- a/src/battle/anim/bug.c
+++ b/src/battle/anim/bug.c
@@ -13,7 +13,7 @@ static void sub_80DCA38(struct Sprite *sprite);
 static void sub_80DCAEC(struct Sprite *sprite);
 static void sub_80DCB5C(struct Sprite *sprite);
 static void sub_80DCBB4(struct Sprite *sprite);
-void sub_80DCD78(struct Sprite *sprite);
+static void AnimMissileArcStep(struct Sprite *sprite);
 
 // used in Move_MEGAHORN
 void sub_80DC824(struct Sprite *sprite)
@@ -174,9 +174,15 @@ static void sub_80DCBB4(struct Sprite *sprite)
     DestroyAnimSprite(sprite);
 }
 
-// used in 3 moves:
-//         Move_POISON_STING, Move_TWINEEDLE, Move_SPIKE_CANNON
-void sub_80DCBCC(struct Sprite *sprite)
+// Translates a stinger sprite linearly to a destination location. The sprite is
+// initially rotated so that it appears to be traveling in a straight line.
+// Used by Move_POISON_STING, Move_TWINEEDLE, Move_SPIKE_CANNON
+// arg 0: initial x pixel offset
+// arg 1: initial y pixel offset
+// arg 2: target x pixel offset
+// arg 3: target y pixel offset
+// arg 4: duration
+void AnimTranslateStinger(struct Sprite *sprite)
 {
     s16 lVarX, lVarY;
     u16 rot;
@@ -216,7 +222,7 @@ void sub_80DCBCC(struct Sprite *sprite)
 
     lVarX = GetBankPosition(gAnimBankTarget, 2) + gBattleAnimArgs[2];
     lVarY = GetBankPosition(gAnimBankTarget, 3) + gBattleAnimArgs[3];
-    rot = sub_80790F0(lVarX - sprite->pos1.x, lVarY - sprite->pos1.y);
+    rot = ArcTan2Neg(lVarX - sprite->pos1.x, lVarY - sprite->pos1.y);
     rot += 0xC000;
     sub_8078FDC(sprite, FALSE, 0x100, 0x100, rot);
 
@@ -230,7 +236,14 @@ void sub_80DCBCC(struct Sprite *sprite)
 
 // used in 2 moves:
 //         Move_PIN_MISSILE, Move_ICICLE_SPEAR
-void sub_80DCCFC(struct Sprite *sprite)
+// Rotates sprite and moves it in an arc, so that it appears like a missle or arrow traveling.
+// arg 0: initial x pixel offset
+// arg 1: initial y pixel offset
+// arg 2: target x pixel offset
+// arg 3: target y pixel offset
+// arg 4: duration
+// arg 5: wave amplitude
+void AnimMissileArc(struct Sprite *sprite)
 {
     InitAnimSpritePos(sprite, 1);
 
@@ -241,13 +254,13 @@ void sub_80DCCFC(struct Sprite *sprite)
     sprite->data[2] = GetBankPosition(gAnimBankTarget, 2) + gBattleAnimArgs[2];
     sprite->data[4] = GetBankPosition(gAnimBankTarget, 3) + gBattleAnimArgs[3];
     sprite->data[5] = gBattleAnimArgs[5];
-    sub_80786EC(sprite);
+    InitAnimSpriteTranslationOverDuration(sprite);
 
-    sprite->callback = sub_80DCD78;
+    sprite->callback = AnimMissileArcStep;
     sprite->invisible = TRUE;
 }
 
-void sub_80DCD78(struct Sprite *sprite)
+static void AnimMissileArcStep(struct Sprite *sprite)
 {
     sprite->invisible = FALSE;
 
@@ -273,10 +286,10 @@ void sub_80DCD78(struct Sprite *sprite)
 
         if (!TranslateAnimSpriteLinearAndSine(sprite))
         {
-            u16 rot = sub_80790F0(sprite->pos1.x + sprite->pos2.x - x2,
+            u16 rotation = ArcTan2Neg(sprite->pos1.x + sprite->pos2.x - x2,
                                   sprite->pos1.y + sprite->pos2.y - y2);
-            rot += 0xC000;
-            sub_8078FDC(sprite, FALSE, 0x100, 0x100, rot);
+            rotation += 0xC000;
+            sub_8078FDC(sprite, FALSE, 0x100, 0x100, rotation);
 
             for (i = 0; i < 8; i++)
                 data[i] = tempData[i];