From 54a628bdfdea51a6618e4fca1958d8027cc8fd55 Mon Sep 17 00:00:00 2001
From: GenericHeroGuy <genericheroguy@noreply.codeberg.org>
Date: Sat, 3 May 2025 17:30:31 +0200
Subject: [PATCH] Enable waypoints for patched maps

---
 src/k_kart.c  |  5 +++++
 src/p_inter.c | 14 ++------------
 src/p_mobj.c  | 37 +++++++++++++++++++++++++++++--------
 src/p_spec.c  |  2 +-
 src/p_spec.h  |  1 +
 5 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/src/k_kart.c b/src/k_kart.c
index 528810383..f1381a410 100644
--- a/src/k_kart.c
+++ b/src/k_kart.c
@@ -11002,6 +11002,11 @@ boolean K_SlipdashActive(void)
 
 boolean K_UsingLegacyCheckpoints(void)
 {
+	if (patch_version && waypointcap)
+	{
+		// we're presumably adding waypoints to an existing map
+		return false;
+	}
 	if (numbosswaypoints > 0)
 	{
 		// We are using Kart V1 waypoints!
diff --git a/src/p_inter.c b/src/p_inter.c
index 357e4d996..9cee82a17 100644
--- a/src/p_inter.c
+++ b/src/p_inter.c
@@ -941,8 +941,8 @@ void P_TouchStarPost(mobj_t *post, player_t *player, boolean snaptopost)
 
 	(void)snaptopost;
 
-	// Player must have touched all previous starposts
-	if ((post->health - player->starpostnum > 1) && (!K_UsingLegacyCheckpoints()))
+	// Going backwards triggers sound
+	if (post->health >= ((numstarposts/2) + player->starpostnum))
 	{
 		if (!player->checkskip)
 		{
@@ -952,17 +952,7 @@ void P_TouchStarPost(mobj_t *post, player_t *player, boolean snaptopost)
 				player->grieftime += TICRATE;
 			}
 
-
 		}
-		player->checkskip = 3;
-		return;
-	}
-
-	// Going backwards triggers sound
-	if ((post->health >= ((numstarposts/2) + player->starpostnum)) && (K_UsingLegacyCheckpoints()))
-	{
-		if (!player->checkskip)
-			S_StartSound(toucher, sfx_s26d);
 
 		player->checkskip = 3;
 		return;
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 9a9f99eca..3ce0d5975 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -12860,15 +12860,22 @@ static boolean P_SetupParticleGen(mapthing_t *mthing, mobj_t *mobj)
 	return true;
 }
 
-static void P_SnapToFinishLine(mobj_t *mobj)
+static void SpreadFinishLine(line_t *line, line_t *prev, boolean flip)
 {
-	line_t *finishline = P_FindNearestLine(mobj->x, mobj->y,
-			mobj->subsector->sector, 2001); // case 2001: Finish Line
-	if (finishline != NULL)
+	size_t i;
+	for (i = 0; i < numlines; i++)
 	{
-		P_UnsetThingPosition(mobj);
-		P_ClosestPointOnLine(mobj->x, mobj->y, finishline, (vertex_t *)&mobj->x);
-		P_SetThingPosition(mobj);
+		line_t *line2 = &lines[i];
+		if (line2 != line && line2 != prev && (line2->slopetype == ST_HORIZONTAL || line2->slopetype == ST_VERTICAL) && line2->slopetype == line->slopetype &&
+		   (line->v1 == line2->v1 || line->v2 == line2->v2 || line->v1 == line2->v2 || line->v2 == line2->v1))
+		{
+			boolean flipped = line->v1 == line2->v1 || line->v2 == line2->v2;
+			line2->special = 2001; // Finish Line
+			line2->activation = SPAC_CROSS|SPAC_REPEATSPECIAL;
+			if (flipped != flip)
+				line2->args[0] |= TMCFF_FLIP;
+			SpreadFinishLine(line2, line, flipped != flip);
+		}
 	}
 }
 
@@ -13161,7 +13168,21 @@ static boolean P_SetupSpawnedMapThing(mapthing_t *mthing, mobj_t *mobj, boolean
 			mobj->extravalue2 = 1; // args[2] of 1 means the waypoint is at the finish line
 			mobj->reactiontime = 0; // Also don't respawn at finish lines
 
-			P_SnapToFinishLine(mobj);
+			line_t *finishline = P_FindNearestLine(mobj->x, mobj->y,
+					mobj->subsector->sector, -1);
+			if (finishline != NULL)
+			{
+				P_UnsetThingPosition(mobj);
+				P_ClosestPointOnLine(mobj->x, mobj->y, finishline, (vertex_t *)&mobj->x);
+				P_SetThingPosition(mobj);
+
+				boolean flip = mthing->args[2] & TMWPF_FLIPFINISH;
+				finishline->special = 2001; // Finish Line
+				finishline->activation = SPAC_CROSS|SPAC_REPEATSPECIAL;
+				if (flip)
+					finishline->args[0] |= TMCFF_FLIP;
+				SpreadFinishLine(finishline, NULL, flip);
+			}
 		}
 		else
 		{
diff --git a/src/p_spec.c b/src/p_spec.c
index a5a068028..8616dc5f2 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -5356,7 +5356,7 @@ static void P_EvaluateSpecialFlags(player_t *player, sector_t *sector, sector_t
 		P_ProcessZoomTube(player, sectag, true);
 	if (sector->specialflags & SSF_FINISHLINE)
 	{
-		if ((gametyperules & GTR_CIRCUIT) && (player->exiting == 0) && !(player->pflags & PF_HITFINISHLINE))
+		if (K_UsingLegacyCheckpoints() && (gametyperules & GTR_CIRCUIT) && (player->exiting == 0) && !(player->pflags & PF_HITFINISHLINE))
 		{
 			K_HandleLapIncrement(player);
 			player->pflags |= PF_HITFINISHLINE;
diff --git a/src/p_spec.h b/src/p_spec.h
index 7bfab7f13..9983829f6 100644
--- a/src/p_spec.h
+++ b/src/p_spec.h
@@ -63,6 +63,7 @@ typedef enum
 	TMWPF_SHORTCUT   = 1<<1,
 	TMWPF_NORESPAWN  = 1<<2,
 	TMWPF_FINISHLINE = 1<<3,
+	TMWPF_FLIPFINISH = 1<<4,
 } textmapwaypointflags_t;
 
 typedef enum