From 934b28989f4b58d5ed2a24567af76251d9bc6db8 Mon Sep 17 00:00:00 2001
From: sphere <spherallic@gmail.com>
Date: Tue, 19 May 2020 23:39:35 +0200
Subject: [PATCH 1/2] Add linedef actions 507 & 508, allow using offsets for
 actions 502-504.

---
 extras/conf/SRB2-22.cfg | 22 ++++++++++++++++++++--
 src/p_spec.c            | 38 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 56 insertions(+), 4 deletions(-)

diff --git a/extras/conf/SRB2-22.cfg b/extras/conf/SRB2-22.cfg
index 7b1b678f2..f4a4baead 100644
--- a/extras/conf/SRB2-22.cfg
+++ b/extras/conf/SRB2-22.cfg
@@ -2611,31 +2611,49 @@ linedeftypes
 		{
 			title = "Scroll Wall According to Linedef";
 			prefix = "(502)";
+			flags128text = "[7] Use texture offsets";
+			flags256text = "[8] Scroll back side";
 		}
 
 		503
 		{
 			title = "Scroll Wall According to Linedef (Accelerative)";
 			prefix = "(503)";
+			flags128text = "[7] Use texture offsets";
+			flags256text = "[8] Scroll back side";
 		}
 
 		504
 		{
 			title = "Scroll Wall According to Linedef (Displacement)";
 			prefix = "(504)";
+			flags128text = "[7] Use texture offsets";
+			flags256text = "[8] Scroll back side";
 		}
 
 		505
 		{
-			title = "Scroll Texture by Front Side Offsets";
+			title = "Scroll Front Wall by Front Side Offsets";
 			prefix = "(505)";
 		}
 
 		506
 		{
-			title = "Scroll Texture by Back Side Offsets";
+			title = "Scroll Front Wall by Back Side Offsets";
 			prefix = "(506)";
 		}
+
+		507
+		{
+			title = "Scroll Back Wall by Front Side Offsets";
+			prefix = "(507)";
+		}
+
+		508
+		{
+			title = "Scroll Back Wall by Back Side Offsets";
+			prefix = "(508)";
+		}
 	}
 
 	planescroll
diff --git a/src/p_spec.c b/src/p_spec.c
index d45a33c47..6bf5b59bc 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -7065,6 +7065,9 @@ void P_SpawnSpecials(boolean fromnetsave)
 			// 503 is used for a scroller
 			// 504 is used for a scroller
 			// 505 is used for a scroller
+			// 506 is used for a scroller
+			// 507 is used for a scroller
+			// 508 is used for a scroller
 			// 510 is used for a scroller
 			// 511 is used for a scroller
 			// 512 is used for a scroller
@@ -7581,7 +7584,20 @@ static void P_SpawnScrollers(void)
 			case 502:
 				for (s = -1; (s = P_FindLineFromTag(l->tag, s)) >= 0 ;)
 					if (s != (INT32)i)
-						Add_Scroller(sc_side, dx, dy, control, lines[s].sidenum[0], accel, 0);
+					{
+						if (l->flags & ML_EFFECT2) // use texture offsets instead
+						{
+							dx = sides[l->sidenum[0]].textureoffset;
+							dy = sides[l->sidenum[0]].rowoffset;
+						}
+						if (l->flags & ML_EFFECT3)
+						{
+							if (lines[s].sidenum[1] != 0xffff)
+								Add_Scroller(sc_side, dx, dy, control, lines[s].sidenum[1], accel, 0);
+						}
+						else
+							Add_Scroller(sc_side, dx, dy, control, lines[s].sidenum[0], accel, 0);
+					}
 				break;
 
 			case 505:
@@ -7595,7 +7611,25 @@ static void P_SpawnScrollers(void)
 				if (s != 0xffff)
 					Add_Scroller(sc_side, -sides[s].textureoffset, sides[s].rowoffset, -1, lines[i].sidenum[0], accel, 0);
 				else
-					CONS_Debug(DBG_GAMELOGIC, "Line special 506 (line #%s) missing 2nd side!\n", sizeu1(i));
+					CONS_Debug(DBG_GAMELOGIC, "Line special 506 (line #%s) missing back side!\n", sizeu1(i));
+				break;
+
+			case 507:
+				s = lines[i].sidenum[0];
+
+				if (lines[i].sidenum[1] != 0xffff)
+					Add_Scroller(sc_side, -sides[s].textureoffset, sides[s].rowoffset, -1, lines[i].sidenum[1], accel, 0);
+				else
+					CONS_Debug(DBG_GAMELOGIC, "Line special 507 (line #%s) missing back side!\n", sizeu1(i));
+				break;
+
+			case 508:
+				s = lines[i].sidenum[1];
+
+				if (s != 0xffff)
+					Add_Scroller(sc_side, -sides[s].textureoffset, sides[s].rowoffset, -1, s, accel, 0);
+				else
+					CONS_Debug(DBG_GAMELOGIC, "Line special 508 (line #%s) missing back side!\n", sizeu1(i));
 				break;
 
 			case 500: // scroll first side

From d6ea89de6fb7fabd13f7aa7bbc19c92e3511aa46 Mon Sep 17 00:00:00 2001
From: sphere <spherallic@gmail.com>
Date: Sat, 23 May 2020 16:41:38 +0200
Subject: [PATCH 2/2] Rename the rest of the wall scrollers in the ZB config.

---
 extras/conf/SRB2-22.cfg | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/extras/conf/SRB2-22.cfg b/extras/conf/SRB2-22.cfg
index f4a4baead..5ed05d4d6 100644
--- a/extras/conf/SRB2-22.cfg
+++ b/extras/conf/SRB2-22.cfg
@@ -2597,19 +2597,19 @@ linedeftypes
 
 		500
 		{
-			title = "Scroll Wall Front Side Left";
+			title = "Scroll Front Wall Left";
 			prefix = "(500)";
 		}
 
 		501
 		{
-			title = "Scroll Wall Front Side Right";
+			title = "Scroll Front Wall Right";
 			prefix = "(501)";
 		}
 
 		502
 		{
-			title = "Scroll Wall According to Linedef";
+			title = "Scroll Tagged Wall";
 			prefix = "(502)";
 			flags128text = "[7] Use texture offsets";
 			flags256text = "[8] Scroll back side";
@@ -2617,7 +2617,7 @@ linedeftypes
 
 		503
 		{
-			title = "Scroll Wall According to Linedef (Accelerative)";
+			title = "Scroll Tagged Wall (Accelerative)";
 			prefix = "(503)";
 			flags128text = "[7] Use texture offsets";
 			flags256text = "[8] Scroll back side";
@@ -2625,7 +2625,7 @@ linedeftypes
 
 		504
 		{
-			title = "Scroll Wall According to Linedef (Displacement)";
+			title = "Scroll Tagged Wall (Displacement)";
 			prefix = "(504)";
 			flags128text = "[7] Use texture offsets";
 			flags256text = "[8] Scroll back side";