Change XYZ Quaking from Major Cooke

- Relative quakes are different from other quakes; all quakes affecting
  the camera do not become relative if one of them is relative.
- Use a single function call to get quake visual parameters instead of four.
- Thrust things in a psuedo-ellipse if they're inside a damaging quake whose
  IntensityX != IntensityY.
- Don't break old savegames.

src/g_shared/a_quake.cpp

@@ -42,12 +42,11 @@ DEarthquake::DEarthquake (AActor *center, int intensityX, int intensityY, int in
 	// Radii are specified in tile units (64 pixels)
 	m_DamageRadius = damrad << (FRACBITS);
 	m_TremorRadius = tremrad << (FRACBITS);
-	m_Intensity = intensityX;
+	m_IntensityX = intensityX;
+	m_IntensityY = intensityY;
+	m_IntensityZ = intensityZ;
 	m_Countdown = duration;
 	m_Flags = flags;
-	m_iX = intensityX;
-	m_iY = intensityY;
-	m_iZ = intensityZ;
 }
 
 //==========================================================================
@@ -58,10 +57,20 @@ DEarthquake::DEarthquake (AActor *center, int intensityX, int intensityY, int in
 
 void DEarthquake::Serialize (FArchive &arc)
 {
-	Super::Serialize (arc); //[MC] m_Intensity is unused now but I don't want to break compatibility...
+	Super::Serialize (arc);
-	arc << m_Spot << m_Intensity << m_Countdown
+	arc << m_Spot << m_IntensityX << m_Countdown
 		<< m_TremorRadius << m_DamageRadius
-		<< m_QuakeSFX << m_Flags << m_iX << m_iY << m_iZ;
+		<< m_QuakeSFX;
+	if (SaveVersion < 4519)
+	{
+		m_IntensityY = m_IntensityX;
+		m_IntensityZ = 0;
+		m_Flags = 0;
+	}
+	else
+	{
+		arc << m_IntensityY << m_IntensityZ << m_Flags;
+	}
 }
 
 //==========================================================================
@@ -106,7 +115,18 @@ void DEarthquake::Tick ()
 					}
 					// Thrust player around
 					angle_t an = victim->angle + ANGLE_1*pr_quake();
-					P_ThrustMobj (victim, an, m_Intensity << (FRACBITS-1));
+					if (m_IntensityX == m_IntensityY)
+					{ // Thrust in a circle
+						P_ThrustMobj (victim, an, m_IntensityX << (FRACBITS-1));
+					}
+					else
+					{ // Thrust in an ellipse
+						an >>= ANGLETOFINESHIFT;
+						// So this is actually completely wrong, but it ought to be good
+						// enough. Otherwise, I'd have to use tangents and square roots.
+						victim->velx += FixedMul(m_IntensityX << (FRACBITS-1), finecosine[an]);
+						victim->vely += FixedMul(m_IntensityY << (FRACBITS-1), finesine[an]);
+					}
 				}
 			}
 		}
@@ -130,18 +150,20 @@ void DEarthquake::Tick ()
 //
 //==========================================================================
 
-int DEarthquake::StaticGetQuakeIntensity (AActor *victim, int selector)
+int DEarthquake::StaticGetQuakeIntensities(AActor *victim,
+	int &x, int &y, int &z, int &relx, int &rely, int &relz)
 {
-	int intensity = 0;
-	int quakeIntensity = 0;
-	TThinkerIterator<DEarthquake> iterator (STAT_EARTHQUAKE);
-	DEarthquake *quake;
-
 	if (victim->player != NULL && (victim->player->cheats & CF_NOCLIP))
 	{
 		return 0;
 	}
 
+	x = y = z = relx = rely = 0;
+
+	TThinkerIterator<DEarthquake> iterator(STAT_EARTHQUAKE);
+	DEarthquake *quake;
+	int count = 0;
+
 	while ( (quake = iterator.Next()) != NULL)
 	{
 		if (quake->m_Spot != NULL)
@@ -150,64 +172,25 @@ int DEarthquake::StaticGetQuakeIntensity (AActor *victim, int selector)
 				victim->y - quake->m_Spot->y);
 			if (dist < quake->m_TremorRadius)
 			{
-				switch (selector)
+				++count;
+				if (quake->m_Flags & QF_RELATIVE)
 				{
-				default:
+					relx = MAX(relx, quake->m_IntensityX);
-				case 0:				
+					rely = MAX(rely, quake->m_IntensityY);
-					quakeIntensity = quake->m_iX;
+					relz = MAX(relz, quake->m_IntensityZ);
-					break;
+				}
-				case 1:
+				else
-					quakeIntensity = quake->m_iY;
+				{
-					break;
+					x = MAX(x, quake->m_IntensityX);
-				case 2:
+					y = MAX(y, quake->m_IntensityY);
-					quakeIntensity = quake->m_iZ;
+					z = MAX(z, quake->m_IntensityZ);
-					break;
-				
 				}
-
-				if (intensity < quakeIntensity)
-					intensity = quakeIntensity;
 			}
 		}
 	}
-	return intensity;
+	return count;
 }
 
-//==========================================================================
-//
-// DEarthquake::StaticGetQuakeIntensity
-//
-// Searches for all quakes near the victim and returns their combined
-// intensity.
-//
-//==========================================================================
-
-int DEarthquake::StaticGetQuakeFlags(AActor *victim)
-{
-	int flags = 0;
-	TThinkerIterator<DEarthquake> iterator(STAT_EARTHQUAKE);
-	DEarthquake *quake;
-
-	if (victim->player != NULL && (victim->player->cheats & CF_NOCLIP))
-	{
-		return 0;
-	}
-
-	while ((quake = iterator.Next()) != NULL)
-	{
-		if (quake->m_Spot != NULL)
-		{
-			fixed_t dist = P_AproxDistance(victim->x - quake->m_Spot->x,
-				victim->y - quake->m_Spot->y);
-			if (dist < quake->m_TremorRadius)
-			{
-				if (!(flags & QF_RELATIVE) && (quake->m_Flags & QF_RELATIVE))
-					flags += QF_RELATIVE;
-			}
-		}
-	}
-	return flags;
-}
 //==========================================================================
 //
 // P_StartQuake

src/g_shared/a_sharedglobal.h

@@ -147,15 +147,12 @@ public:
 	void Tick ();
 	TObjPtr<AActor> m_Spot;
 	fixed_t m_TremorRadius, m_DamageRadius;
-	int m_Intensity;
 	int m_Countdown;
 	FSoundID m_QuakeSFX;
 	int m_Flags;
-	int m_iX, m_iY, m_iZ;
+	int m_IntensityX, m_IntensityY, m_IntensityZ;
-
-	static int StaticGetQuakeFlags(AActor *viewer);
-	static int StaticGetQuakeIntensity (AActor *viewer, int selector);
 
+	static int StaticGetQuakeIntensities(AActor *viewer, int &x, int &y, int &z, int &relx, int &rely, int &relz);
 
 private:
 	DEarthquake ();

src/r_utility.cpp

@@ -764,6 +764,23 @@ bool R_GetViewInterpolationStatus()
 	return NoInterpolateView;
 }
 
+//==========================================================================
+//
+// QuakePower
+//
+//==========================================================================
+
+static fixed_t QuakePower(fixed_t factor, int intensity)
+{
+	if (intensity == 0)
+	{
+		return 0;
+	}
+	else
+	{
+		return factor * ((pr_torchflicker() % (intensity << 2)) - (intensity << 1));
+	}
+}
 
 //==========================================================================
 //
@@ -875,37 +892,41 @@ void R_SetupFrame (AActor *actor)
 
 	if (!paused)
 	{
-		int intensityX = DEarthquake::StaticGetQuakeIntensity(camera, 0);
+		int intensityX, intensityY, intensityZ, relIntensityX, relIntensityY, relIntensityZ;
-		int intensityY = DEarthquake::StaticGetQuakeIntensity(camera, 1);
+		if (DEarthquake::StaticGetQuakeIntensities(camera,
-		int intensityZ = DEarthquake::StaticGetQuakeIntensity(camera, 2);
+			intensityX, intensityY, intensityZ,
-		int quakeflags = DEarthquake::StaticGetQuakeFlags(camera);
+			relIntensityX, relIntensityY, relIntensityZ) > 0)
-		if (intensityX || intensityY || intensityZ)
 		{
 			fixed_t quakefactor = FLOAT2FIXED(r_quakeintensity);
 
-			if ((quakeflags & QF_RELATIVE) && (intensityX != intensityY))
+			if (relIntensityX != 0)
 			{
-				if (intensityX)
+				int ang = (camera->angle) >> ANGLETOFINESHIFT;
-				{
+				fixed_t power = QuakePower(quakefactor, relIntensityX);
-					int ang = (camera->angle) >> ANGLETOFINESHIFT;
+				viewx += FixedMul(finecosine[ang], power);
-					int tflicker = pr_torchflicker();
+				viewy += FixedMul(finesine[ang], power);
-					viewx += FixedMul(finecosine[ang], (quakefactor * ((tflicker % (intensityX << 2)) - (intensityX << 1))));
-					viewy += FixedMul(finesine[ang], (quakefactor * ((tflicker % (intensityX << 2)) - (intensityX << 1))));
-				}
-				if (intensityY)
-				{
-					int ang = (camera->angle + ANG90) >> ANGLETOFINESHIFT;
-					int tflicker = pr_torchflicker();
-					viewx += FixedMul(finecosine[ang], (quakefactor * ((tflicker % (intensityY << 2)) - (intensityY << 1))));
-					viewy += FixedMul(finesine[ang], (quakefactor * ((tflicker % (intensityY << 2)) - (intensityY << 1))));
-				}
 			}
-			else
+			if (relIntensityY != 0)
 			{
-				if (intensityX)	viewx += quakefactor * ((pr_torchflicker() % (intensityX << 2)) - (intensityX << 1));
+				int ang = (camera->angle + ANG90) >> ANGLETOFINESHIFT;
-				if (intensityY)	viewy += quakefactor * ((pr_torchflicker() % (intensityY << 2)) - (intensityY << 1));
+				fixed_t power = QuakePower(quakefactor, relIntensityY);
+				viewx += FixedMul(finecosine[ang], power);
+				viewy += FixedMul(finesine[ang], power);
+			}
+			if (intensityX != 0)
+			{
+				viewx += QuakePower(quakefactor, intensityX);
+			}
+			if (intensityY != 0)
+			{
+				viewy += QuakePower(quakefactor, intensityY);
+			}
+			// FIXME: Relative Z is not relative
+			intensityZ = MAX(intensityZ, relIntensityZ);
+			if (intensityZ != 0)
+			{
+				viewz += QuakePower(quakefactor, intensityZ);
 			}
-			if (intensityZ)	viewz += quakefactor * ((pr_torchflicker() % (intensityZ << 2)) - (intensityZ << 1));
 		}
 	}
 

src/version.h

@@ -76,7 +76,7 @@ const char *GetVersionString();
 
 // Use 4500 as the base git save version, since it's higher than the
 // SVN revision ever got.
-#define SAVEVER 4518
+#define SAVEVER 4519
 
 #define SAVEVERSTRINGIFY2(x) #x
 #define SAVEVERSTRINGIFY(x) SAVEVERSTRINGIFY2(x)