From 652fb5452e5f87192056e01ac93e3914a5436c24 Mon Sep 17 00:00:00 2001
From: James R <justsomejames2@gmail.com>
Date: Sun, 2 Apr 2023 05:21:01 -0700
Subject: [PATCH] MF_NOCLIPHEIGHT: remove restrictions on first-person camera

Fixes spectator noclip camera being clamped to
floor/ceiling heights.
---
 src/p_mobj.c |  5 +++--
 src/p_user.c | 19 +++++++++++++++----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/p_mobj.c b/src/p_mobj.c
index 1604257ca..4322e8478 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -2839,8 +2839,9 @@ void P_PlayerZMovement(mobj_t *mo)
 		P_AdjustMobjFloorZ_PolyObjs(mo, mo->subsector);
 
 	// check for smooth step up
-	if ((mo->eflags & MFE_VERTICALFLIP && mo->z + mo->height > mo->ceilingz)
-		|| (!(mo->eflags & MFE_VERTICALFLIP) && mo->z < mo->floorz))
+	if (!(mo->flags & MF_NOCLIPHEIGHT)
+		&& ((mo->eflags & MFE_VERTICALFLIP && mo->z + mo->height > mo->ceilingz)
+		|| (!(mo->eflags & MFE_VERTICALFLIP) && mo->z < mo->floorz)))
 	{
 		if (mo->eflags & MFE_VERTICALFLIP)
 			mo->player->viewheight -= (mo->z+mo->height) - mo->ceilingz;
diff --git a/src/p_user.c b/src/p_user.c
index 7529c12ad..9f539f541 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -220,12 +220,20 @@ void P_CalcHeight(player_t *player)
 		if (mo->eflags & MFE_VERTICALFLIP)
 		{
 			player->viewz = mo->z + mo->height - player->viewheight;
+
+			if (mo->flags & MF_NOCLIPHEIGHT)
+				return;
+
 			if (player->viewz < mo->floorz + FixedMul(FRACUNIT, mo->scale))
 				player->viewz = mo->floorz + FixedMul(FRACUNIT, mo->scale);
 		}
 		else
 		{
 			player->viewz = mo->z + player->viewheight;
+
+			if (mo->flags & MF_NOCLIPHEIGHT)
+				return;
+
 			if (player->viewz > mo->ceilingz - FixedMul(FRACUNIT, mo->scale))
 				player->viewz = mo->ceilingz - FixedMul(FRACUNIT, mo->scale);
 		}
@@ -2300,10 +2308,13 @@ static void P_SpectatorMovement(player_t *player)
 	else if (cmd->buttons & BT_BRAKE)
 		player->mo->z -= 32*mapobjectscale;
 
-	if (player->mo->z > player->mo->ceilingz - player->mo->height)
-		player->mo->z = player->mo->ceilingz - player->mo->height;
-	if (player->mo->z < player->mo->floorz)
-		player->mo->z = player->mo->floorz;
+	if (!(player->mo->flags & MF_NOCLIPHEIGHT))
+	{
+		if (player->mo->z > player->mo->ceilingz - player->mo->height)
+			player->mo->z = player->mo->ceilingz - player->mo->height;
+		if (player->mo->z < player->mo->floorz)
+			player->mo->z = player->mo->floorz;
+	}
 
 	player->mo->momx = player->mo->momy = player->mo->momz = 0;
 	if (cmd->forwardmove != 0)