Search FOF target sectors for slope anchors

Requires spawning fake floors before slopes, and therefore before things,
basically before everything. Hopefully nothing breaks!

src/p_setup.c

@@ -3206,19 +3206,22 @@ boolean P_SetupLevel(boolean skipprecip)
 	// anything that P_ResetDynamicSlopes/P_LoadThings needs to know
 	P_InitSpecials();
 
+	// set up world state
+	// jart: needs to be done here so anchored slopes know the attached list
+	P_SpawnSpecials(fromnetsave);
+
 	P_ResetDynamicSlopes();
 
 	P_LoadThings();
 
+	P_RaiseThings();
+
 	P_SpawnSecretItems(loademblems);
 
 	for (numcoopstarts = 0; numcoopstarts < MAXPLAYERS; numcoopstarts++)
 		if (!playerstarts[numcoopstarts])
 			break;
 
-	// set up world state
-	P_SpawnSpecials(fromnetsave);
-
 	K_AdjustWaypointsParameters();
 
 	if (loadprecip) //  ugly hack for P_NetUnArchiveMisc (and P_LoadNetGame)

src/p_spec.c

@@ -5358,6 +5358,26 @@ P_RaiseTaggedThingsToFakeFloor (
 	}
 }
 
+void
+P_RaiseThings (void)
+{
+	size_t i;
+
+	for (i = 0; i < numlines; ++i)
+	{
+		switch (lines[i].special)
+		{
+			case 80: // Raise tagged things by type to this FOF
+				P_RaiseTaggedThingsToFakeFloor(
+						( sides[lines[i].sidenum[0]].textureoffset >> FRACBITS ),
+						lines[i].tag,
+						lines[i].frontsector
+				);
+				break;
+		}
+	}
+}
+
 //
 // SPECIAL SPAWNING
 //
@@ -6822,22 +6842,6 @@ void P_SpawnSpecials(INT32 fromnetsave)
 		}
 	}
 
-	/* some things have to be done after FOF spawn */
-
-	for (i = 0; i < numlines; ++i)
-	{
-		switch (lines[i].special)
-		{
-			case 80: // Raise tagged things by type to this FOF
-				P_RaiseTaggedThingsToFakeFloor(
-						( sides[lines[i].sidenum[0]].textureoffset >> FRACBITS ),
-						lines[i].tag,
-						lines[i].frontsector
-				);
-				break;
-		}
-	}
-
 	// Allocate each list
 	for (i = 0; i < numsectors; i++)
 		if(secthinkers[i].thinkers)

src/p_spec.h

@@ -38,6 +38,7 @@ void P_SetupLevelFlatAnims(void);
 // at map load
 void P_InitSpecials(void);
 void P_SpawnSpecials(INT32 fromnetsave);
+void P_RaiseThings(void);
 
 // every tic
 void P_UpdateSpecials(void);

src/slope_anchors.c

@@ -266,6 +266,8 @@ find_closest_anchors
 
 	int last = 0;
 
+	size_t i;
+
 	if (list->count < 3)
 	{
 		I_Error("At least three slope anchors are required to make a slope.");
@@ -273,7 +275,18 @@ find_closest_anchors
 
 	anchors = Z_Malloc(3 * sizeof *anchors, PU_LEVEL, NULL);
 
-	get_sector_anchors(anchors, distances, list, sector);
+	if (sector->numattached > 0)
+	{
+		for (i = 0; i < sector->numattached; ++i)
+		{
+			get_sector_anchors
+				(anchors, distances, list, &sectors[sector->attached[i]]);
+		}
+	}
+	else
+	{
+		get_sector_anchors(anchors, distances, list, sector);
+	}
 
 	if (distances[2] < INT32_MAX)
 	{
@@ -287,13 +300,36 @@ find_closest_anchors
 	else
 		last = 0;
 
-	I_Error(
-			"(Sector #%s)"
-			" Slope requires anchors near 3 of its vertices (%d found)",
+	if (sector->numattached > 0)
+	{
+		CONS_Printf("\nSearched for anchors in sectors...\n\n");
 
-			sizeu1 (sector - sectors),
-			last
-	);
+		for (i = 0; i < sector->numattached; ++i)
+		{
+			CONS_Printf("#%s\n", sizeu1 (sector->attached[i]));
+		}
+
+		I_Error(
+				"(Control Sector #%s)"
+				" Slope requires anchors near 3 of its target sectors' vertices"
+				" (%d found)"
+
+				"\n\nCheck the log to see which sectors were searched.",
+
+				sizeu1 (sector - sectors),
+				last
+		);
+	}
+	else
+	{
+		I_Error(
+				"(Sector #%s)"
+				" Slope requires anchors near 3 of its vertices (%d found)",
+
+				sizeu1 (sector - sectors),
+				last
+		);
+	}
 }
 
 static pslope_t *