diff --git a/appveyor.yml b/appveyor.yml
index cc073ff01..23b9b6281 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -47,7 +47,7 @@ before_build:
 - upx -V
 - ccache -V
 - ccache -s
-- set SRB2_MFLAGS=-C src MINGW=1 WARNINGMODE=1 GCC63=1 CCACHE=1
+- set SRB2_MFLAGS=-C src MINGW=1 WARNINGMODE=1 GCC63=1 CCACHE=1 NOOBJDUMP=1
 
 build_script:
 - cmd: mingw32-make.exe %SRB2_MFLAGS% %CONFIGURATION%=1 clean
diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index 19b58b0d3..8af95531c 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -3975,7 +3975,7 @@ FILESTAMP
 			if (client)
 			{
 				INT32 i;
-				for (i = 0; i < MAXNETNODES; i++)
+				for (i = 0; i < MAXPLAYERS; i++)
 					if (playeringame[i])
 						playerpingtable[i] = (tic_t)netbuffer->u.pingtable[i];
 			}
@@ -4533,8 +4533,8 @@ static inline void PingUpdate(void)
 	}
 
 	//send out our ping packets
-	for (i = 0; i < MAXPLAYERS; i++)
-		if (playeringame[i])
+	for (i = 0; i < MAXNETNODES; i++)
+		if (nodeingame[i])
 			HSendPacket(i, true, 0, sizeof(INT32) * MAXPLAYERS);
 
 	pingmeasurecount = 1; //Reset count
@@ -4564,20 +4564,15 @@ void NetUpdate(void)
 
 	gametime = nowtime;
 
-	if (!(gametime % 255) && netgame && server)
-	{
-#ifdef NEWPING
-		PingUpdate();
-#endif
-	}
-
 #ifdef NEWPING
 	if (server)
 	{
+		if (netgame && !(gametime % 255))
+			PingUpdate();
 		// update node latency values so we can take an average later.
-		for (i = 0; i < MAXNETNODES; i++)
+		for (i = 0; i < MAXPLAYERS; i++)
 			if (playeringame[i])
-				realpingtable[i] += G_TicsToMilliseconds(GetLag(i));
+				realpingtable[i] += G_TicsToMilliseconds(GetLag(playernode[i]));
 		pingmeasurecount++;
 	}
 #endif
diff --git a/src/doomdef.h b/src/doomdef.h
index 6737cf6d1..16d7fa218 100644
--- a/src/doomdef.h
+++ b/src/doomdef.h
@@ -546,4 +546,8 @@ extern const char *compdate, *comptime, *comprevision, *compbranch;
 /// Hudname padding.
 #define SKINNAMEPADDING
 
+/// Handle touching sector specials in P_PlayerAfterThink instead of P_PlayerThink.
+/// \note   Required for proper collision with moving sloped surfaces that have sector specials on them.
+//#define SECTORSPECIALSAFTERTHINK
+
 #endif // __DOOMDEF__
diff --git a/src/g_game.c b/src/g_game.c
index 40878a70f..7769555ba 100644
--- a/src/g_game.c
+++ b/src/g_game.c
@@ -2309,6 +2309,9 @@ void G_SpawnPlayer(INT32 playernum, boolean starpost)
 	if (starpost) //Don't even bother with looking for a place to spawn.
 	{
 		P_MovePlayerToStarpost(playernum);
+#ifdef HAVE_BLUA
+		LUAh_PlayerSpawn(&players[playernum]); // Lua hook for player spawning :)
+#endif
 		return;
 	}
 
@@ -3930,7 +3933,7 @@ void G_GhostAddColor(ghostcolor_t color)
 	ghostext.color = (UINT8)color;
 }
 
-void G_GhostAddScale(UINT16 scale)
+void G_GhostAddScale(fixed_t scale)
 {
 	if (!demorecording || !(demoflags & DF_GHOST))
 		return;
diff --git a/src/g_game.h b/src/g_game.h
index 145c3ec93..72a6f3d6e 100644
--- a/src/g_game.h
+++ b/src/g_game.h
@@ -142,7 +142,7 @@ void G_GhostAddSpin(void);
 void G_GhostAddRev(void);
 void G_GhostAddColor(ghostcolor_t color);
 void G_GhostAddFlip(void);
-void G_GhostAddScale(UINT16 scale);
+void G_GhostAddScale(fixed_t scale);
 void G_GhostAddHit(mobj_t *victim);
 void G_WriteGhostTic(mobj_t *ghost);
 void G_ConsGhostTic(void);
diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index e15713e27..4cfbc59e9 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -1084,9 +1084,9 @@ static void HWR_SplitWall(sector_t *sector, wallVert3D *wallVerts, INT32 texnum,
 	float endheight = 0.0f, endbheight = 0.0f;
 
 	fixed_t v1x = FLOAT_TO_FIXED(wallVerts[0].x);
-	fixed_t v1y = FLOAT_TO_FIXED(wallVerts[0].y);
+	fixed_t v1y = FLOAT_TO_FIXED(wallVerts[0].z); // not a typo
 	fixed_t v2x = FLOAT_TO_FIXED(wallVerts[1].x);
-	fixed_t v2y = FLOAT_TO_FIXED(wallVerts[1].y);
+	fixed_t v2y = FLOAT_TO_FIXED(wallVerts[1].z); // not a typo
 	// compiler complains when P_GetZAt is used in FLOAT_TO_FIXED directly
 	// use this as a temp var to store P_GetZAt's return value each time
 	fixed_t temp;
@@ -3721,6 +3721,9 @@ static void HWR_Subsector(size_t num)
 
 		while (count--)
 		{
+#ifdef POLYOBJECTS
+				if (!line->polyseg) // ignore segs that belong to polyobjects
+#endif
 				HWR_AddLine(line);
 				line++;
 		}
diff --git a/src/hardware/r_opengl/r_opengl.c b/src/hardware/r_opengl/r_opengl.c
index 3a0bf7054..e6ff83e89 100644
--- a/src/hardware/r_opengl/r_opengl.c
+++ b/src/hardware/r_opengl/r_opengl.c
@@ -244,6 +244,7 @@ FUNCPRINTF void DBG_Printf(const char *lpFmt, ...)
 #define pglMaterialfv glMaterialfv
 
 /* Raster functions */
+#define pglPixelStorei glPixelStorei
 #define pglReadPixels glReadPixels
 
 /* Texture mapping */
@@ -262,15 +263,8 @@ FUNCPRINTF void DBG_Printf(const char *lpFmt, ...)
 /* texture mapping */ //GL_EXT_copy_texture
 #ifndef KOS_GL_COMPATIBILITY
 #define pglCopyTexImage2D glCopyTexImage2D
+#endif
 
-/* GLU functions */
-#define pgluBuild2DMipmaps gluBuild2DMipmaps
-#endif
-#ifndef MINI_GL_COMPATIBILITY
-/* 1.3 functions for multitexturing */
-#define pglActiveTexture glActiveTexture
-#define pglMultiTexCoord2f glMultiTexCoord2f
-#endif
 #else //!STATIC_OPENGL
 
 /* 1.0 functions */
@@ -365,6 +359,8 @@ typedef void (APIENTRY * PFNglMaterialfv) (GLint face, GLenum pname, GLfloat *pa
 static PFNglMaterialfv pglMaterialfv;
 
 /* Raster functions */
+typedef void (APIENTRY * PFNglPixelStorei) (GLenum pname, GLint param);
+static PFNglPixelStorei pglPixelStorei;
 typedef void (APIENTRY  * PFNglReadPixels) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLvoid *pixels);
 static PFNglReadPixels pglReadPixels;
 
@@ -391,7 +387,7 @@ static PFNglBindTexture pglBindTexture;
 /* texture mapping */ //GL_EXT_copy_texture
 typedef void (APIENTRY * PFNglCopyTexImage2D) (GLenum target, GLint level, GLenum internalformat, GLint x, GLint y, GLsizei width, GLsizei height, GLint border);
 static PFNglCopyTexImage2D pglCopyTexImage2D;
-
+#endif
 /* GLU functions */
 typedef GLint (APIENTRY * PFNgluBuild2DMipmaps) (GLenum target, GLint internalFormat, GLsizei width, GLsizei height, GLenum format, GLenum type, const void *data);
 static PFNgluBuild2DMipmaps pgluBuild2DMipmaps;
@@ -403,7 +399,6 @@ static PFNglActiveTexture pglActiveTexture;
 typedef void (APIENTRY *PFNglMultiTexCoord2f) (GLenum, GLfloat, GLfloat);
 static PFNglMultiTexCoord2f pglMultiTexCoord2f;
 #endif
-#endif
 
 #ifndef MINI_GL_COMPATIBILITY
 /* 1.2 Parms */
@@ -494,6 +489,7 @@ boolean SetupGLfunc(void)
 	GETOPENGLFUNC(pglLightModelfv , glLightModelfv)
 	GETOPENGLFUNC(pglMaterialfv , glMaterialfv)
 
+	GETOPENGLFUNC(pglPixelStorei , glPixelStorei)
 	GETOPENGLFUNC(pglReadPixels , glReadPixels)
 
 	GETOPENGLFUNC(pglTexEnvi , glTexEnvi)
@@ -519,35 +515,23 @@ boolean SetupGLfunc(void)
 // This has to be done after the context is created so the version number can be obtained
 boolean SetupGLFunc13(void)
 {
+#ifdef MINI_GL_COMPATIBILITY
+	return false;
+#else
 	const GLubyte *version = pglGetString(GL_VERSION);
 	int glmajor, glminor;
 
 	gl13 = false;
-#ifdef MINI_GL_COMPATIBILITY
-	return false;
-#else
-#ifdef STATIC_OPENGL
-	gl13 = true;
-#else
-
 	// Parse the GL version
 	if (version != NULL)
 	{
 		if (sscanf((const char*)version, "%d.%d", &glmajor, &glminor) == 2)
 		{
 			// Look, we gotta prepare for the inevitable arrival of GL 2.0 code...
-			switch (glmajor)
-			{
-				case 1:
-					if (glminor == 3) gl13 = true;
-					break;
-				case 2:
-				case 3:
-				case 4:
-					gl13 = true;
-				default:
-					break;
-			}
+			if (glmajor == 1 && glminor >= 3)
+				gl13 = true;
+			else if (glmajor > 1)
+				gl13 = true;
 		}
 	}
 
@@ -568,9 +552,6 @@ boolean SetupGLFunc13(void)
 	}
 	else
 		DBG_Printf("GL_ARB_multitexture support: disabled\n");
-#undef GETOPENGLFUNC
-
-#endif
 	return true;
 #endif
 }
@@ -897,7 +878,9 @@ EXPORT void HWRAPI(ReadRect) (INT32 x, INT32 y, INT32 width, INT32 height,
 		GLubyte*top = (GLvoid*)dst_data, *bottom = top + dst_stride * (height - 1);
 		GLubyte *row = malloc(dst_stride);
 		if (!row) return;
+		pglPixelStorei(GL_PACK_ALIGNMENT, 1);
 		pglReadPixels(x, y, width, height, GL_RGB, GL_UNSIGNED_BYTE, dst_data);
+		pglPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 		for(i = 0; i < height/2; i++)
 		{
 			memcpy(row, top, dst_stride);
@@ -913,7 +896,9 @@ EXPORT void HWRAPI(ReadRect) (INT32 x, INT32 y, INT32 width, INT32 height,
 		INT32 j;
 		GLubyte *image = malloc(width*height*3*sizeof (*image));
 		if (!image) return;
+		pglPixelStorei(GL_PACK_ALIGNMENT, 1);
 		pglReadPixels(x, y, width, height, GL_RGB, GL_UNSIGNED_BYTE, image);
+		pglPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 		for (i = height-1; i >= 0; i--)
 		{
 			for (j = 0; j < width; j++)
@@ -1815,13 +1800,11 @@ EXPORT void HWRAPI(SetSpecialState) (hwdspecialstate_t IdState, INT32 Value)
 					min_filter = GL_NEAREST;
 #endif
 			}
-#ifndef STATIC_OPENGL
 			if (!pgluBuild2DMipmaps)
 			{
 				MipMap = GL_FALSE;
 				min_filter = GL_LINEAR;
 			}
-#endif
 			Flush(); //??? if we want to change filter mode by texture, remove this
 			break;
 
diff --git a/src/p_floor.c b/src/p_floor.c
index 68c3d55b8..1ed1d1565 100644
--- a/src/p_floor.c
+++ b/src/p_floor.c
@@ -2113,6 +2113,7 @@ void T_EachTimeThinker(levelspecthink_t *eachtime)
 	boolean inAndOut = false;
 	boolean floortouch = false;
 	fixed_t bottomheight, topheight;
+	msecnode_t *node;
 
 	for (i = 0; i < MAXPLAYERS; i++)
 	{
@@ -2174,7 +2175,23 @@ void T_EachTimeThinker(levelspecthink_t *eachtime)
 					if ((netgame || multiplayer) && players[j].spectator)
 						continue;
 
-					if (players[j].mo->subsector->sector != targetsec)
+					if (players[j].mo->subsector->sector == targetsec)
+						;
+					else if (sec->flags & SF_TRIGGERSPECIAL_TOUCH)
+					{
+						boolean insector = false;
+						for (node = players[j].mo->touching_sectorlist; node; node = node->m_sectorlist_next)
+						{
+							if (node->m_sector == targetsec)
+							{
+								insector = true;
+								break;
+							}
+						}
+						if (!insector)
+							continue;
+					}
+					else
 						continue;
 
 					topheight = P_GetSpecialTopZ(players[j].mo, sec, targetsec);
@@ -2224,7 +2241,27 @@ void T_EachTimeThinker(levelspecthink_t *eachtime)
 				if ((netgame || multiplayer) && players[i].spectator)
 					continue;
 
-				if (players[i].mo->subsector->sector != sec)
+				if (players[i].mo->subsector->sector == sec)
+					;
+				else if (sec->flags & SF_TRIGGERSPECIAL_TOUCH)
+				{
+					boolean insector = false;
+					for (node = players[i].mo->touching_sectorlist; node; node = node->m_sectorlist_next)
+					{
+						if (node->m_sector == sec)
+						{
+							insector = true;
+							break;
+						}
+					}
+					if (!insector)
+						continue;
+				}
+				else
+					continue;
+
+				if (!(players[i].mo->subsector->sector == sec
+					|| P_PlayerTouchingSectorSpecial(&players[i], 2, (GETSECSPECIAL(sec->special, 2))) == sec))
 					continue;
 
 				if (floortouch == true && P_IsObjectOnGroundIn(players[i].mo, sec))
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 1d83e8706..e1ac9f714 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -2560,10 +2560,18 @@ boolean P_CheckSolidLava(mobj_t *mo, ffloor_t *rover)
 	I_Assert(mo != NULL);
 	I_Assert(!P_MobjWasRemoved(mo));
 
-	if (rover->flags & FF_SWIMMABLE && GETSECSPECIAL(rover->master->frontsector->special, 1) == 3
-		&& !(rover->master->flags & ML_BLOCKMONSTERS)
-		&& ((rover->master->flags & ML_EFFECT3) || mo->z-mo->momz > *rover->topheight - FixedMul(16*FRACUNIT, mo->scale)))
-			return true;
+	{
+		fixed_t topheight =
+	#ifdef ESLOPE
+			*rover->t_slope ? P_GetZAt(*rover->t_slope, mo->x, mo->y) :
+	#endif
+			*rover->topheight;
+
+		if (rover->flags & FF_SWIMMABLE && GETSECSPECIAL(rover->master->frontsector->special, 1) == 3
+			&& !(rover->master->flags & ML_BLOCKMONSTERS)
+			&& ((rover->master->flags & ML_EFFECT3) || mo->z-mo->momz > topheight - FixedMul(16*FRACUNIT, mo->scale)))
+				return true;
+	}
 
 	return false;
 }
@@ -3578,11 +3586,17 @@ static boolean P_SceneryZMovement(mobj_t *mo)
 //
 boolean P_CanRunOnWater(player_t *player, ffloor_t *rover)
 {
+	fixed_t topheight =
+#ifdef ESLOPE
+		*rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) :
+#endif
+		*rover->topheight;
+
 	if (!player->powers[pw_carry] && !player->homing
-		&& ((player->powers[pw_super] || player->charflags & SF_RUNONWATER || player->dashmode >= 3*TICRATE) && player->mo->ceilingz-*rover->topheight >= player->mo->height)
+		&& ((player->powers[pw_super] || player->charflags & SF_RUNONWATER || player->dashmode >= 3*TICRATE) && player->mo->ceilingz-topheight >= player->mo->height)
 		&& (rover->flags & FF_SWIMMABLE) && !(player->pflags & PF_SPINNING) && player->speed > FixedMul(player->runspeed, player->mo->scale)
 		&& !(player->pflags & PF_SLIDING)
-		&& abs(player->mo->z - *rover->topheight) < FixedMul(30*FRACUNIT, player->mo->scale))
+		&& abs(player->mo->z - topheight) < FixedMul(30*FRACUNIT, player->mo->scale))
 		return true;
 
 	return false;
diff --git a/src/p_spec.c b/src/p_spec.c
index 5dfa515f0..b2e2cba95 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -2444,73 +2444,81 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 
 		case 414: // Play SFX
 			{
-				fixed_t sfxnum;
+				INT32 sfxnum;
 
 				sfxnum = sides[line->sidenum[0]].toptexture;
 
-				if (line->tag != 0 && line->flags & ML_EFFECT5)
+				if (sfxnum == sfx_None)
+					return; // Do nothing!
+				if (sfxnum < sfx_None || sfxnum >= NUMSFX)
 				{
-					sector_t *sec;
-
-					while ((secnum = P_FindSectorFromLineTag(line, secnum)) >= 0)
+					CONS_Debug(DBG_GAMELOGIC, "Line type 414 Executor: sfx number %d is invalid!\n", sfxnum);
+					return;
+				}
+				if (line->tag != 0) // Do special stuff only if a non-zero linedef tag is set
+				{
+					if (line->flags & ML_EFFECT5) // Repeat Midtexture
 					{
-						sec = &sectors[secnum];
-						S_StartSound(&sec->soundorg, sfxnum);
+						// Additionally play the sound from tagged sectors' soundorgs
+						sector_t *sec;
+
+						while ((secnum = P_FindSectorFromLineTag(line, secnum)) >= 0)
+						{
+							sec = &sectors[secnum];
+							S_StartSound(&sec->soundorg, sfxnum);
+						}
+					}
+					else if (mo) // A mobj must have triggered the executor
+					{
+						// Only trigger if mobj is touching the tag
+						ffloor_t *rover;
+						boolean foundit = false;
+
+						for(rover = mo->subsector->sector->ffloors; rover; rover = rover->next)
+						{
+							if (rover->master->frontsector->tag != line->tag)
+								continue;
+
+							if (mo->z > P_GetSpecialTopZ(mo, sectors + rover->secnum, mo->subsector->sector))
+								continue;
+
+							if (mo->z + mo->height < P_GetSpecialBottomZ(mo, sectors + rover->secnum, mo->subsector->sector))
+								continue;
+
+							foundit = true;
+						}
+
+						if (mo->subsector->sector->tag == line->tag)
+							foundit = true;
+
+						if (!foundit)
+							return;
 					}
 				}
-				else if (line->tag != 0 && mo)
+
+				if (line->flags & ML_NOCLIMB)
 				{
-					// Only trigger if mobj is touching the tag
-					ffloor_t *rover;
-					boolean foundit = false;
-
-					for(rover = mo->subsector->sector->ffloors; rover; rover = rover->next)
-					{
-						if (rover->master->frontsector->tag != line->tag)
-							continue;
-
-						if (mo->z > P_GetSpecialTopZ(mo, sectors + rover->secnum, mo->subsector->sector))
-							continue;
-
-						if (mo->z + mo->height < P_GetSpecialBottomZ(mo, sectors + rover->secnum, mo->subsector->sector))
-							continue;
-
-						foundit = true;
-					}
-
-					if (mo->subsector->sector->tag == line->tag)
-						foundit = true;
-
-					if (!foundit)
-						return;
-				}
-
-				if (sfxnum < NUMSFX && sfxnum > sfx_None)
-				{
-					if (line->flags & ML_NOCLIMB)
-					{
-						// play the sound from nowhere, but only if display player triggered it
-						if (mo && mo->player && (mo->player == &players[displayplayer] || mo->player == &players[secondarydisplayplayer]))
-							S_StartSound(NULL, sfxnum);
-					}
-					else if (line->flags & ML_EFFECT4)
-					{
-						// play the sound from nowhere
+					// play the sound from nowhere, but only if display player triggered it
+					if (mo && mo->player && (mo->player == &players[displayplayer] || mo->player == &players[secondarydisplayplayer]))
 						S_StartSound(NULL, sfxnum);
-					}
-					else if (line->flags & ML_BLOCKMONSTERS)
-					{
-						// play the sound from calling sector's soundorg
-						if (callsec)
-							S_StartSound(&callsec->soundorg, sfxnum);
-						else if (mo)
-							S_StartSound(&mo->subsector->sector->soundorg, sfxnum);
-					}
+				}
+				else if (line->flags & ML_EFFECT4)
+				{
+					// play the sound from nowhere
+					S_StartSound(NULL, sfxnum);
+				}
+				else if (line->flags & ML_BLOCKMONSTERS)
+				{
+					// play the sound from calling sector's soundorg
+					if (callsec)
+						S_StartSound(&callsec->soundorg, sfxnum);
 					else if (mo)
-					{
-						// play the sound from mobj that triggered it
-						S_StartSound(mo, sfxnum);
-					}
+						S_StartSound(&mo->subsector->sector->soundorg, sfxnum);
+				}
+				else if (mo)
+				{
+					// play the sound from mobj that triggered it
+					S_StartSound(mo, sfxnum);
 				}
 			}
 			break;
@@ -3569,7 +3577,7 @@ static boolean P_ThingIsOnThe3DFloor(mobj_t *mo, sector_t *sector, sector_t *tar
 //
 // Is player standing on the sector's "ground"?
 //
-static inline boolean P_MobjReadyToTrigger(mobj_t *mo, sector_t *sec)
+static boolean P_MobjReadyToTrigger(mobj_t *mo, sector_t *sec)
 {
 	if (mo->eflags & MFE_VERTICALFLIP)
 		return (mo->z+mo->height == P_GetSpecialTopZ(mo, sec, sec) && sec->flags & SF_FLIPSPECIAL_CEILING);
@@ -3702,14 +3710,49 @@ void P_ProcessSpecialSector(player_t *player, sector_t *sector, sector_t *rovers
 				{
 					if (roversector)
 					{
-						if (players[i].mo->subsector->sector != roversector)
+						if (players[i].mo->subsector->sector == roversector)
+							;
+						else if (sector->flags & SF_TRIGGERSPECIAL_TOUCH)
+						{
+							boolean insector = false;
+							msecnode_t *node;
+							for (node = players[i].mo->touching_sectorlist; node; node = node->m_sectorlist_next)
+							{
+								if (node->m_sector == roversector)
+								{
+									insector = true;
+									break;
+								}
+							}
+							if (!insector)
+								goto DoneSection2;
+						}
+						else
 							goto DoneSection2;
+
 						if (!P_ThingIsOnThe3DFloor(players[i].mo, sector, roversector))
 							goto DoneSection2;
 					}
 					else
 					{
-						if (players[i].mo->subsector->sector != sector)
+						if (players[i].mo->subsector->sector == sector)
+							;
+						else if (sector->flags & SF_TRIGGERSPECIAL_TOUCH)
+						{
+							boolean insector = false;
+							msecnode_t *node;
+							for (node = players[i].mo->touching_sectorlist; node; node = node->m_sectorlist_next)
+							{
+								if (node->m_sector == sector)
+								{
+									insector = true;
+									break;
+								}
+							}
+							if (!insector)
+								goto DoneSection2;
+						}
+						else
 							goto DoneSection2;
 
 						if (special == 3 && !P_MobjReadyToTrigger(players[i].mo, sector))
@@ -4490,6 +4533,7 @@ sector_t *P_ThingOnSpecial3DFloor(mobj_t *mo)
 {
 	sector_t *sector;
 	ffloor_t *rover;
+	fixed_t topheight, bottomheight;
 
 	sector = mo->subsector->sector;
 	if (!sector->ffloors)
@@ -4497,8 +4541,6 @@ sector_t *P_ThingOnSpecial3DFloor(mobj_t *mo)
 
 	for (rover = sector->ffloors; rover; rover = rover->next)
 	{
-		fixed_t topheight, bottomheight;
-
 		if (!rover->master->frontsector->special)
 			continue;
 
@@ -4546,6 +4588,8 @@ sector_t *P_ThingOnSpecial3DFloor(mobj_t *mo)
 	return NULL;
 }
 
+#define TELEPORTED (player->mo->subsector->sector != originalsector)
+
 /** Checks if a player is standing on or is inside a 3D floor (e.g. water) and
   * applies any specials.
   *
@@ -4554,12 +4598,12 @@ sector_t *P_ThingOnSpecial3DFloor(mobj_t *mo)
   */
 static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 {
+	sector_t *originalsector = player->mo->subsector->sector;
 	ffloor_t *rover;
+	fixed_t topheight, bottomheight;
 
 	for (rover = sector->ffloors; rover; rover = rover->next)
 	{
-		fixed_t topheight, bottomheight;
-
 		if (!rover->master->frontsector->special)
 			continue;
 
@@ -4603,7 +4647,10 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 		// This FOF has the special we're looking for, but are we allowed to touch it?
 		if (sector == player->mo->subsector->sector
 			|| (rover->master->frontsector->flags & SF_TRIGGERSPECIAL_TOUCH))
+		{
 			P_ProcessSpecialSector(player, rover->master->frontsector, sector);
+			if TELEPORTED return;
+		}
 	}
 
 	// Allow sector specials to be applied to polyobjects!
@@ -4614,7 +4661,7 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 		boolean touching = false;
 		boolean inside = false;
 
-		while(po)
+		while (po)
 		{
 			if (po->flags & POF_NOSPECIALS)
 			{
@@ -4690,6 +4737,7 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 			}
 
 			P_ProcessSpecialSector(player, polysec, sector);
+			if TELEPORTED return;
 
 			po = (polyobj_t *)(po->link.next);
 		}
@@ -4794,40 +4842,43 @@ static void P_RunSpecialSectorCheck(player_t *player, sector_t *sector)
   */
 void P_PlayerInSpecialSector(player_t *player)
 {
-	sector_t *sector;
+	sector_t *originalsector;
+	sector_t *loopsector;
 	msecnode_t *node;
 
 	if (!player->mo)
 		return;
 
-	// Do your ->subsector->sector first
-	sector = player->mo->subsector->sector;
-	P_PlayerOnSpecial3DFloor(player, sector);
-	// After P_PlayerOnSpecial3DFloor, recheck if the player is in that sector,
-	// because the player can be teleported in between these times.
-	if (sector == player->mo->subsector->sector)
-		P_RunSpecialSectorCheck(player, sector);
+	originalsector = player->mo->subsector->sector;
 
-	// Iterate through touching_sectorlist
+	P_PlayerOnSpecial3DFloor(player, originalsector); // Handle FOFs first.
+	if TELEPORTED return;
+
+	P_RunSpecialSectorCheck(player, originalsector);
+	if TELEPORTED return;
+
+	// Iterate through touching_sectorlist for SF_TRIGGERSPECIAL_TOUCH
 	for (node = player->mo->touching_sectorlist; node; node = node->m_sectorlist_next)
 	{
-		sector = node->m_sector;
+		loopsector = node->m_sector;
 
-		if (sector == player->mo->subsector->sector) // Don't duplicate
+		if (loopsector == originalsector) // Don't duplicate
 			continue;
 
 		// Check 3D floors...
-		P_PlayerOnSpecial3DFloor(player, sector);
+		P_PlayerOnSpecial3DFloor(player, loopsector);
+		if TELEPORTED return;
 
-		if (!(sector->flags & SF_TRIGGERSPECIAL_TOUCH))
-			return;
-		// After P_PlayerOnSpecial3DFloor, recheck if the player is in that sector,
-		// because the player can be teleported in between these times.
-		if (sector == player->mo->subsector->sector)
-			P_RunSpecialSectorCheck(player, sector);
+		if (!(loopsector->flags & SF_TRIGGERSPECIAL_TOUCH))
+			continue;
+
+		P_RunSpecialSectorCheck(player, loopsector);
+		if TELEPORTED return;
 	}
 }
 
+#undef TELEPORTED
+
 /** Animate planes, scroll walls, etc. and keeps track of level timelimit and exits if time is up.
   *
   * \sa P_CheckTimeLimit, P_CheckPointLimit
diff --git a/src/p_user.c b/src/p_user.c
index 8ce1d08d7..9ae79e5e2 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -1706,9 +1706,8 @@ void P_DoPlayerExit(player_t *player)
 #define SPACESPECIAL 12
 boolean P_InSpaceSector(mobj_t *mo) // Returns true if you are in space
 {
-	sector_t *sector;
-
-	sector = mo->subsector->sector;
+	sector_t *sector = mo->subsector->sector;
+	fixed_t topheight, bottomheight;
 
 	if (GETSECSPECIAL(sector->special, 1) == SPACESPECIAL)
 		return true;
@@ -1721,11 +1720,18 @@ boolean P_InSpaceSector(mobj_t *mo) // Returns true if you are in space
 		{
 			if (GETSECSPECIAL(rover->master->frontsector->special, 1) != SPACESPECIAL)
 				continue;
+#ifdef ESLOPE
+			topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, mo->x, mo->y) : *rover->topheight;
+			bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, mo->x, mo->y) : *rover->bottomheight;
+#else
+			topheight = *rover->topheight;
+			bottomheight = *rover->bottomheight;
+#endif
 
-			if (mo->z > *rover->topheight)
+			if (mo->z + (mo->height/2) > topheight)
 				continue;
 
-			if (mo->z + (mo->height/2) < *rover->bottomheight)
+			if (mo->z + (mo->height/2) < bottomheight)
 				continue;
 
 			return true;
@@ -1737,9 +1743,10 @@ boolean P_InSpaceSector(mobj_t *mo) // Returns true if you are in space
 
 boolean P_InQuicksand(mobj_t *mo) // Returns true if you are in quicksand
 {
-	sector_t *sector;
+	sector_t *sector = mo->subsector->sector;
+	fixed_t topheight, bottomheight;
 
-	sector = mo->subsector->sector;
+	fixed_t flipoffset = ((mo->eflags & MFE_VERTICALFLIP) ? (mo->height/2) : 0);
 
 	if (sector->ffloors)
 	{
@@ -1753,10 +1760,18 @@ boolean P_InQuicksand(mobj_t *mo) // Returns true if you are in quicksand
 			if (!(rover->flags & FF_QUICKSAND))
 				continue;
 
-			if (mo->z > *rover->topheight)
+#ifdef ESLOPE
+			topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, mo->x, mo->y) : *rover->topheight;
+			bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, mo->x, mo->y) : *rover->bottomheight;
+#else
+			topheight = *rover->topheight;
+			bottomheight = *rover->bottomheight;
+#endif
+
+			if (mo->z + flipoffset > topheight)
 				continue;
 
-			if (mo->z + (mo->height/2) < *rover->bottomheight)
+			if (mo->z + (mo->height/2) + flipoffset < bottomheight)
 				continue;
 
 			return true;
@@ -2067,6 +2082,7 @@ static void P_CheckQuicksand(player_t *player)
 {
 	ffloor_t *rover;
 	fixed_t sinkspeed, friction;
+	fixed_t topheight, bottomheight;
 
 	if (!(player->mo->subsector->sector->ffloors && player->mo->momz <= 0))
 		return;
@@ -2078,16 +2094,38 @@ static void P_CheckQuicksand(player_t *player)
 		if (!(rover->flags & FF_QUICKSAND))
 			continue;
 
-		if (*rover->topheight >= player->mo->z && *rover->bottomheight < player->mo->z + player->mo->height)
+#ifdef ESLOPE
+		topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+		bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+#else
+		topheight = *rover->topheight;
+		bottomheight = *rover->bottomheight;
+#endif
+
+		if (topheight >= player->mo->z && bottomheight < player->mo->z + player->mo->height)
 		{
 			sinkspeed = abs(rover->master->v1->x - rover->master->v2->x)>>1;
 
 			sinkspeed = FixedDiv(sinkspeed,TICRATE*FRACUNIT);
 
-			player->mo->z -= sinkspeed;
+			if (player->mo->eflags & MFE_VERTICALFLIP)
+			{
+				fixed_t ceilingheight = P_GetCeilingZ(player->mo, player->mo->subsector->sector, player->mo->x, player->mo->y, NULL);
 
-			if (player->mo->z <= player->mo->subsector->sector->floorheight)
-				player->mo->z = player->mo->subsector->sector->floorheight;
+				player->mo->z += sinkspeed;
+
+				if (player->mo->z + player->mo->height >= ceilingheight)
+					player->mo->z = ceilingheight - player->mo->height;
+			}
+			else
+			{
+				fixed_t floorheight = P_GetFloorZ(player->mo, player->mo->subsector->sector, player->mo->x, player->mo->y, NULL);
+
+				player->mo->z -= sinkspeed;
+
+				if (player->mo->z <= floorheight)
+					player->mo->z = floorheight;
+			}
 
 			friction = abs(rover->master->v1->y - rover->master->v2->y)>>6;
 
@@ -2437,11 +2475,11 @@ static void P_DoClimbing(player_t *player)
 					floorclimb = true;
 
 #ifdef ESLOPE
-					bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
 					topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+					bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
 #else
-					bottomheight = *rover->bottomheight;
 					topheight = *rover->topheight;
+					bottomheight = *rover->bottomheight;
 #endif
 
 					// Only supports rovers that are moving like an 'elevator', not just the top or bottom.
@@ -2630,13 +2668,20 @@ static void P_DoClimbing(player_t *player)
 					// Is there a FOF directly below that we can move onto?
 					if (glidesector->sector->ffloors)
 					{
+						fixed_t topheight;
 						ffloor_t *rover;
 						for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 						{
 							if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
 								continue;
 
-							if (*rover->topheight > ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
+#ifdef ESLOPE
+							topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+#else
+							topheight = *rover->topheight;
+#endif
+
+							if (topheight > ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
 							{
 								foundfof = true;
 								break;
@@ -3014,14 +3059,12 @@ static void P_DoTeeter(player_t *player)
 			{
 				if (!(rover->flags & FF_EXISTS)) continue;
 
+#ifdef ESLOPE
+				topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+				bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+#else
 				topheight = *rover->topheight;
 				bottomheight = *rover->bottomheight;
-
-#ifdef ESLOPE
-				if (*rover->t_slope)
-					topheight = P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y);
-				if (*rover->b_slope)
-					bottomheight = P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y);
 #endif
 
 				if (P_CheckSolidLava(player->mo, rover))
@@ -9007,13 +9050,23 @@ static void P_CalcPostImg(player_t *player)
 	else if (sector->ffloors)
 	{
 		ffloor_t *rover;
+		fixed_t topheight;
+		fixed_t bottomheight;
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
 			if (!(rover->flags & FF_EXISTS))
 				continue;
 
-			if (pviewheight >= *rover->topheight || pviewheight <= *rover->bottomheight)
+#ifdef ESLOPE
+			topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+			bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+#else
+			topheight = *rover->topheight;
+			bottomheight = *rover->bottomheight;
+#endif
+
+			if (pviewheight >= topheight || pviewheight <= bottomheight)
 				continue;
 
 			if (P_FindSpecialLineFromTag(13, rover->master->frontsector->tag, -1) != -1)
@@ -9025,13 +9078,23 @@ static void P_CalcPostImg(player_t *player)
 	if (sector->ffloors)
 	{
 		ffloor_t *rover;
+		fixed_t topheight;
+		fixed_t bottomheight;
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
 			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE) || rover->flags & FF_BLOCKPLAYER)
 				continue;
 
-			if (pviewheight >= *rover->topheight || pviewheight <= *rover->bottomheight)
+#ifdef ESLOPE
+			topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+			bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+#else
+			topheight = *rover->topheight;
+			bottomheight = *rover->bottomheight;
+#endif
+
+			if (pviewheight >= topheight || pviewheight <= bottomheight)
 				continue;
 
 			*type = postimg_water;
@@ -9263,6 +9326,7 @@ void P_PlayerThink(player_t *player)
 	// check water content, set stuff in mobj
 	P_MobjCheckWater(player->mo);
 
+#ifndef SECTORSPECIALSAFTERTHINK
 #ifdef POLYOBJECTS
 	if (player->onconveyor != 1 || !P_IsObjectOnGround(player->mo))
 #endif
@@ -9271,6 +9335,7 @@ void P_PlayerThink(player_t *player)
 
 	if (!player->spectator)
 		P_PlayerInSpecialSector(player);
+#endif
 
 	if (player->playerstate == PST_DEAD)
 	{
@@ -9662,6 +9727,17 @@ void P_PlayerAfterThink(player_t *player)
 
 	cmd = &player->cmd;
 
+#ifdef SECTORSPECIALSAFTERTHINK
+#ifdef POLYOBJECTS
+	if (player->onconveyor != 1 || !P_IsObjectOnGround(player->mo))
+#endif
+	player->onconveyor = 0;
+	// check special sectors : damage & secrets
+
+	if (!player->spectator)
+		P_PlayerInSpecialSector(player);
+#endif
+
 	if (splitscreen && player == &players[secondarydisplayplayer])
 		thiscam = &camera2;
 	else if (player == &players[displayplayer])
diff --git a/src/r_bsp.c b/src/r_bsp.c
index 44cb991a7..abb11204a 100644
--- a/src/r_bsp.c
+++ b/src/r_bsp.c
@@ -1222,6 +1222,9 @@ static void R_Subsector(size_t num)
 	while (count--)
 	{
 //		CONS_Debug(DBG_GAMELOGIC, "Adding normal line %d...(%d)\n", line->linedef-lines, leveltime);
+#ifdef POLYOBJECTS
+		if (!line->polyseg) // ignore segs that belong to polyobjects
+#endif
 		R_AddLine(line);
 		line++;
 		curline = NULL; /* cph 2001/11/18 - must clear curline now we're done with it, so stuff doesn't try using it for other things */
diff --git a/src/sdl/ogl_sdl.c b/src/sdl/ogl_sdl.c
index 21afd831d..cd7ced7ca 100644
--- a/src/sdl/ogl_sdl.c
+++ b/src/sdl/ogl_sdl.c
@@ -71,7 +71,6 @@ INT32 oglflags = 0;
 void *GLUhandle = NULL;
 SDL_GLContext sdlglcontext = 0;
 
-#ifndef STATIC_OPENGL
 void *GetGLFunc(const char *proc)
 {
 	if (strncmp(proc, "glu", 3) == 0)
@@ -83,7 +82,6 @@ void *GetGLFunc(const char *proc)
 	}
 	return SDL_GL_GetProcAddress(proc);
 }
-#endif
 
 boolean LoadGL(void)
 {