From faf127ff8860e18c5cba47572ca629527b0e4779 Mon Sep 17 00:00:00 2001
From: Nev3r <apophycens@gmail.com>
Date: Sat, 4 Jan 2020 10:39:45 +0100
Subject: [PATCH] Add vertex slope spawning function. Rename
 P_ResetDynamicSlopes() to P_SpawnSlopes().

---
 src/p_setup.c  |  2 +-
 src/p_slopes.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++---
 src/p_slopes.h |  2 +-
 3 files changed, 59 insertions(+), 5 deletions(-)

diff --git a/src/p_setup.c b/src/p_setup.c
index 0a802583a..a1aaeb4ba 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -3582,7 +3582,7 @@ boolean P_LoadLevel(boolean fromnetsave)
 	P_InitSpecials();
 
 #ifdef ESLOPE
-	P_ResetDynamicSlopes(fromnetsave);
+	P_SpawnSlopes(fromnetsave);
 #endif
 
 	P_SpawnMapThings(!fromnetsave);
diff --git a/src/p_slopes.c b/src/p_slopes.c
index e66d7ed21..5c47c7226 100644
--- a/src/p_slopes.c
+++ b/src/p_slopes.c
@@ -507,6 +507,56 @@ static void line_SpawnViaVertexes(const int linenum, const boolean spawnthinker)
 	side->sector->hasslope = true;
 }
 
+/// Spawn textmap vertex slopes.
+void SpawnVertexSlopes (void)
+{
+	line_t *l1, *l2;
+	sector_t* sc;
+	vertex_t *v1, *v2, *v3;
+	size_t i;
+	for (i = 0, sc = sectors; i < numsectors; i++, sc++)
+	{
+		// The vertex slopes only work for 3-vertex sectors (and thus 3-sided sectors).
+		if (sc->linecount != 3)
+			continue;
+
+		l1 = sc->lines[0];
+		l2 = sc->lines[1];
+
+		// Determine the vertexes.
+		v1 = l1->v1;
+		v2 = l1->v2;
+		if ((l2->v1 != v1) && (l2->v1 != v2))
+			v3 = l2->v1;
+		else
+			v3 = l2->v2;
+
+		if (v1->floorzset || v2->floorzset || v3->floorzset)
+		{
+			vector3_t vtx[3] = {
+				{v1->x, v1->y, v1->floorzset == true ? v1->floorz : sc->floorheight},
+				{v2->x, v2->y, v2->floorzset == true ? v2->floorz : sc->floorheight},
+				{v3->x, v3->y, v3->floorzset == true ? v3->floorz : sc->floorheight}};
+			pslope_t* slop = Slope_Add(0);
+			sc->f_slope = slop;
+			sc->hasslope = true;
+			ReconfigureViaVertexes(slop, vtx[0], vtx[1], vtx[2]);
+		}
+
+		if (v1->ceilingzset || v2->ceilingzset || v3->ceilingzset)
+		{
+			vector3_t vtx[3] = {
+				{v1->x, v1->y, v1->ceilingzset == true ? v1->ceilingz : sc->ceilingheight},
+				{v2->x, v2->y, v2->ceilingzset == true ? v2->ceilingz : sc->ceilingheight},
+				{v3->x, v3->y, v3->ceilingzset == true ? v3->ceilingz : sc->ceilingheight}};
+			pslope_t* slop = Slope_Add(0);
+			sc->c_slope = slop;
+			sc->hasslope = true;
+			ReconfigureViaVertexes(slop, vtx[0], vtx[1], vtx[2]);
+		}
+
+	}
+}
 
 //
 // P_CopySectorSlope
@@ -551,12 +601,16 @@ pslope_t *P_SlopeById(UINT16 id)
 	return ret;
 }
 
-/// Reset slopes and read them from special lines.
-void P_ResetDynamicSlopes(const boolean fromsave) {
+/// Initializes and reads the slopes from the map data.
+void P_SpawnSlopes(const boolean fromsave) {
 	size_t i;
+
 	slopelist = NULL;
 	slopecount = 0;
 
+	/// Generates vertex slopes.
+	SpawnVertexSlopes();
+
 	/// Generates line special-defined slopes.
 	for (i = 0; i < numlines; i++)
 	{
@@ -577,7 +631,7 @@ void P_ResetDynamicSlopes(const boolean fromsave) {
 			case 705:
 			case 714:
 			case 715:
-				line_SpawnViaVertexes(i, !fromsave);
+				line_SpawnViaVertexes(i, !fromsave); // Mapthing-based vertex slopes.
 				break;
 
 			default:
diff --git a/src/p_slopes.h b/src/p_slopes.h
index 96764051b..0bf03f26d 100644
--- a/src/p_slopes.h
+++ b/src/p_slopes.h
@@ -23,7 +23,7 @@ extern UINT16 slopecount;
 void P_LinkSlopeThinkers (void);
 
 void P_CalculateSlopeNormal(pslope_t *slope);
-void P_ResetDynamicSlopes(const boolean fromsave);
+void P_SpawnSlopes(const boolean fromsave);
 
 //
 // P_CopySectorSlope