From a8fe25dd41ae65b494913cd2570e1630bd285892 Mon Sep 17 00:00:00 2001
From: James R <justsomejames2@gmail.com>
Date: Sat, 25 Jan 2020 23:36:24 -0800
Subject: [PATCH] QUAAAAAAAAKE

---
 src/p_local.h |  1 +
 src/p_user.c  | 36 ++++++++++++++++++++++++++++++++++++
 src/r_main.c  |  1 +
 3 files changed, 38 insertions(+)

diff --git a/src/p_local.h b/src/p_local.h
index 0300cffa4..4c657eca6 100644
--- a/src/p_local.h
+++ b/src/p_local.h
@@ -134,6 +134,7 @@ extern consvar_t cv_cam_speed[MAXSPLITSCREENPLAYERS], cv_cam_rotate[MAXSPLITSCRE
 
 extern fixed_t t_cam_dist[MAXSPLITSCREENPLAYERS], t_cam_height[MAXSPLITSCREENPLAYERS], t_cam_rotate[MAXSPLITSCREENPLAYERS];
 extern consvar_t cv_inverseslope;
+extern consvar_t cv_quaketilt;
 
 void P_AddPlayerScore(player_t *player, UINT32 amount);
 void P_ResetCamera(player_t *player, camera_t *thiscam);
diff --git a/src/p_user.c b/src/p_user.c
index 2dc6b60b7..0c0c0d67e 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -2726,6 +2726,7 @@ consvar_t cv_cam_rotate[MAXSPLITSCREENPLAYERS] = {
 };
 
 consvar_t cv_inverseslope = {"inverseslope", "Off", CV_SAVE, CV_OnOff, NULL, 0, NULL, NULL, 0, 0, NULL};
+consvar_t cv_quaketilt = {"quaketilt", "On", CV_SAVE, CV_OnOff, NULL, 0, NULL, NULL, 0, 0, NULL};
 
 fixed_t t_cam_dist[MAXSPLITSCREENPLAYERS] = {-42,-42,-42,-42};
 fixed_t t_cam_height[MAXSPLITSCREENPLAYERS] = {-42,-42,-42,-42};
@@ -4164,6 +4165,38 @@ static void P_HandleFollower(player_t *player)
 
 	/* gaysed script from me, based on Golden's sprite slope roll */
 
+// holy SHIT
+static INT32
+Quaketilt (player_t *player)
+{
+	angle_t tilt;
+	fixed_t lowb; // this threshold for speed
+	angle_t moma = R_PointToAngle2(0, 0, player->mo->momx, player->mo->momy);
+	angle_t delta = (INT32)( player->mo->angle - moma );
+	fixed_t speed;
+	// Hi! I'm "not a math guy"!
+	if (abs(delta) > ANGLE_90)
+		delta = (INT32)(( moma + ANGLE_180 ) - player->mo->angle );
+	if (P_IsObjectOnGround(player->mo))
+	{
+		tilt = ANGLE_11hh;
+		lowb = 15*FRACUNIT;
+	}
+	else
+	{
+		tilt = ANGLE_45;
+		lowb = 10*FRACUNIT;
+	}
+	moma = FixedMul(FixedDiv(delta, ANGLE_90), tilt);
+	speed = abs( player->mo->momx + player->mo->momy );
+	if (speed < lowb)
+	{
+		// ease out tilt as we slow...
+		moma = FixedMul(moma, FixedDiv(speed, lowb));
+	}
+	return moma;
+}
+
 static void
 DoABarrelRoll (player_t *player)
 {
@@ -4181,6 +4214,9 @@ DoABarrelRoll (player_t *player)
 	else
 		slope = 0;
 
+	if (cv_quaketilt.value)
+		slope += Quaketilt(player);
+
 	delta = (INT32)( slope - player->viewrollangle )/ 16;
 
 	if (delta)
diff --git a/src/r_main.c b/src/r_main.c
index 7f7000588..d3762de3c 100644
--- a/src/r_main.c
+++ b/src/r_main.c
@@ -1706,6 +1706,7 @@ void R_RegisterEngineStuff(void)
 	}
 
 	CV_RegisterVar(&cv_inverseslope);
+	CV_RegisterVar(&cv_quaketilt);
 
 	CV_RegisterVar(&cv_showhud);
 	CV_RegisterVar(&cv_translucenthud);