Merge branch 'jelly-racers' into 'master'

Squashing and stretching

See merge request KartKrew/Kart!420

src/k_kart.c

@@ -4510,6 +4510,42 @@ void K_DriftDustHandling(mobj_t *spawner)
 	}
 }
 
+void K_Squish(mobj_t *mo)
+{
+	const fixed_t maxstretch = 4*FRACUNIT;
+	const fixed_t factor = 3 * mo->height / 2;
+	const fixed_t threshold = factor / 6;
+
+	const fixed_t old3dspeed = abs(mo->lastmomz);
+	const fixed_t new3dspeed = abs(mo->momz);
+
+	const fixed_t delta = abs(old3dspeed - new3dspeed);
+
+	if (delta > threshold)
+	{
+		mo->spritexscale =
+			FRACUNIT + FixedDiv(delta, factor);
+
+		if (mo->spritexscale > maxstretch)
+			mo->spritexscale = maxstretch;
+
+		if (abs(new3dspeed) > abs(old3dspeed))
+		{
+			mo->spritexscale =
+				FixedDiv(FRACUNIT, mo->spritexscale);
+		}
+	}
+	else
+	{
+		mo->spritexscale -=
+			(mo->spritexscale - FRACUNIT)
+			/ (mo->spritexscale < FRACUNIT ? 8 : 2);
+	}
+
+	mo->spriteyscale =
+		FixedDiv(FRACUNIT, mo->spritexscale);
+}
+
 static mobj_t *K_FindLastTrailMobj(player_t *player)
 {
 	mobj_t *trail;

src/k_kart.h

@@ -76,6 +76,7 @@ void K_SpawnSparkleTrail(mobj_t *mo);
 void K_SpawnWipeoutTrail(mobj_t *mo, boolean offroad);
 void K_SpawnDraftDust(mobj_t *mo);
 void K_DriftDustHandling(mobj_t *spawner);
+void K_Squish(mobj_t *mo);
 mobj_t *K_ThrowKartItem(player_t *player, boolean missile, mobjtype_t mapthing, INT32 defaultDir, INT32 altthrow);
 void K_PuntMine(mobj_t *mine, mobj_t *punter);
 void K_DoSneaker(player_t *player, INT32 type);

src/p_mobj.c

@@ -3511,6 +3511,16 @@ static void P_CheckFloatbobPlatforms(mobj_t *mobj)
 	}
 }
 
+static void P_SquishThink(mobj_t *mobj)
+{
+	if (!(mobj->eflags & MFE_SLOPELAUNCHED))
+	{
+		K_Squish(mobj);
+	}
+
+	mobj->lastmomz = mobj->momz;
+}
+
 static void P_PlayerMobjThinker(mobj_t *mobj)
 {
 	I_Assert(mobj != NULL);
@@ -3576,6 +3586,8 @@ static void P_PlayerMobjThinker(mobj_t *mobj)
 		mobj->eflags &= ~MFE_JUSTHITFLOOR;
 	}
 
+	P_SquishThink(mobj);
+
 animonly:
 	P_CyclePlayerMobjState(mobj);
 }
@@ -8626,7 +8638,7 @@ void P_MobjThinker(mobj_t *mobj)
 		return;
 	}
 
-	mobj->eflags &= ~(MFE_PUSHED|MFE_SPRUNG|MFE_JUSTBOUNCEDWALL|MFE_DAMAGEHITLAG);
+	mobj->eflags &= ~(MFE_PUSHED|MFE_SPRUNG|MFE_JUSTBOUNCEDWALL|MFE_DAMAGEHITLAG|MFE_SLOPELAUNCHED);
 
 	tmfloorthing = tmhitthing = NULL;
 
@@ -8815,6 +8827,8 @@ void P_MobjThinker(mobj_t *mobj)
 		P_ButteredSlope(mobj);
 	}
 
+	P_SquishThink(mobj);
+
 	if (mobj->flags & (MF_ENEMY|MF_BOSS) && mobj->health
 		&& P_CheckDeathPitCollide(mobj)) // extra pit check in case these didn't have momz
 	{

src/p_mobj.h

@@ -249,6 +249,8 @@ typedef enum
 	MFE_JUSTBOUNCEDWALL   = 1<<12,
 	// SRB2Kart: In damage hitlag (displays different visual efx)
 	MFE_DAMAGEHITLAG      = 1<<13,
+	// Slope physics sent you airborne
+	MFE_SLOPELAUNCHED     = 1<<14,
 	// free: to and including 1<<15
 } mobjeflag_t;
 
@@ -361,6 +363,7 @@ typedef struct mobj_s
 
 	fixed_t friction;
 	fixed_t movefactor;
+	fixed_t lastmomz;
 
 	INT32 fuse; // Does something in P_MobjThinker on reaching 0.
 	fixed_t watertop; // top of the water FOF the mobj is in

src/p_saveg.c

@@ -1534,7 +1534,8 @@ typedef enum
 	MD2_HITLAG       = 1<<24,
 	MD2_WAYPOINTCAP  = 1<<25,
 	MD2_KITEMCAP     = 1<<26,
-	MD2_ITNEXT       = 1<<27
+	MD2_ITNEXT       = 1<<27,
+	MD2_LASTMOMZ     = 1<<28,
 } mobj_diff2_t;
 
 typedef enum
@@ -1775,6 +1776,8 @@ static void SaveMobjThinker(const thinker_t *th, const UINT8 type)
 		diff2 |= MD2_KITEMCAP;
 	if (mobj->itnext)
 		diff2 |= MD2_ITNEXT;
+	if (mobj->lastmomz)
+		diff2 |= MD2_LASTMOMZ;
 
 	if (diff2 != 0)
 		diff |= MD_MORE;
@@ -1968,6 +1971,10 @@ static void SaveMobjThinker(const thinker_t *th, const UINT8 type)
 	{
 		WRITEINT32(save_p, mobj->hitlag);
 	}
+	if (diff2 & MD2_LASTMOMZ)
+	{
+		WRITEINT32(save_p, mobj->lastmomz);
+	}
 
 	WRITEUINT32(save_p, mobj->mobjnum);
 }
@@ -3062,6 +3069,10 @@ static thinker_t* LoadMobjThinker(actionf_p1 thinker)
 	{
 		mobj->hitlag = READINT32(save_p);
 	}
+	if (diff2 & MD2_LASTMOMZ)
+	{
+		mobj->lastmomz = READINT32(save_p);
+	}
 
 	if (diff & MD_REDFLAG)
 	{

src/p_slopes.c

@@ -844,6 +844,8 @@ void P_SlopeLaunch(mobj_t *mo)
 		mo->momy = slopemom.y;
 		mo->momz = slopemom.z;
 #endif
+
+		mo->eflags |= MFE_SLOPELAUNCHED;
 	}
 
 	//CONS_Printf("Launched off of slope.\n");