From e2037f149e61d37656d45cc6b3f1675c1d4180d6 Mon Sep 17 00:00:00 2001
From: NepDisk <16447892+NepDisk@users.noreply.github.com>
Date: Mon, 29 Jul 2024 02:23:54 -0400
Subject: [PATCH] Fix skyboxes, and make butteredslopes nice

---
 src/deh_soc.c  |  3 +++
 src/info.c     |  2 +-
 src/p_slopes.c | 42 +++++++++++++++++++-----------------------
 3 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/src/deh_soc.c b/src/deh_soc.c
index 8617ad3bb..c600d21f7 100644
--- a/src/deh_soc.c
+++ b/src/deh_soc.c
@@ -1551,6 +1551,9 @@ void readlevelheader(MYFILE *f, INT32 num)
 			else if (fastcmp(word, "SKYTEXTURE"))
 				deh_strlcpy(mapheaderinfo[num-1]->skytexture, word2,
 					sizeof(mapheaderinfo[num-1]->skytexture), va("Level header %d: sky texture", num));
+			else if (fastcmp(word, "SKYNUM"))
+				deh_strlcpy(mapheaderinfo[num-1]->skytexture, va("SKY%s", word2),
+					sizeof(mapheaderinfo[num-1]->skytexture), va("Level header %d: sky texture", num));
 			else if (fastcmp(word, "PRECUTSCENENUM"))
 				mapheaderinfo[num-1]->precutscenenum = (UINT8)i;
 			else if (fastcmp(word, "CUTSCENENUM"))
diff --git a/src/info.c b/src/info.c
index 794689a6f..f8d573ab4 100644
--- a/src/info.c
+++ b/src/info.c
@@ -3843,7 +3843,7 @@ state_t states[NUMSTATES] =
 	{SPR_RNDM, 18|FF_FULLBRIGHT|FF_ANIMATE|FF_GLOBALANIM, 4, {NULL}, 1, 1, S_RANDOMITEM11},	// S_RANDOMITEM10
 	{SPR_RNDM, 20|FF_FULLBRIGHT|FF_ANIMATE|FF_GLOBALANIM, 4, {NULL}, 1, 1, S_RANDOMITEM12},	// S_RANDOMITEM11
 	{SPR_RNDM, 22|FF_FULLBRIGHT|FF_ANIMATE|FF_GLOBALANIM, 4, {NULL}, 1, 1, S_RANDOMITEM1},	// S_RANDOMITEM12
-	{SPR_NULL, 0, 0, {A_ItemPop}, 0, 0, S_NULL},											// S_DEADRANDOMITEM
+	{SPR_NULL, 0, 0, {A_ItemPop}, 0, 0, S_RANDOMITEM1},											// S_DEADRANDOMITEM
 
 	{SPR_SBOX,    FF_FULLBRIGHT|FF_ANIMATE|FF_GLOBALANIM, 4, {NULL}, 1, 1, S_SPHEREBOX2},	// S_SPHEREBOX1
 	{SPR_SBOX,  2|FF_FULLBRIGHT|FF_ANIMATE|FF_GLOBALANIM, 4, {NULL}, 1, 1, S_SPHEREBOX3},	// S_SPHEREBOX2
diff --git a/src/p_slopes.c b/src/p_slopes.c
index 6c749506b..871ef929b 100644
--- a/src/p_slopes.c
+++ b/src/p_slopes.c
@@ -1069,47 +1069,43 @@ void P_ButteredSlope(mobj_t *mo)
 {
 	fixed_t thrust;
 
+	if (!mo->standingslope)
+		return;
+
+	if (mo->standingslope->flags & SL_NOPHYSICS)
+		return; // No physics, no butter.
+
 	if (mo->flags & (MF_NOCLIPHEIGHT|MF_NOGRAVITY))
 		return; // don't slide down slopes if you can't touch them or you're not affected by gravity
 
-	if (P_CanApplySlopePhysics(mo, mo->standingslope) == false)
-		return; // No physics, no butter.
+	if (mo->player) {
+		if (abs(mo->standingslope->zdelta) < FRACUNIT/4)
+			return; // Don't slide on non-steep slopes unless spinning
 
-	if (mo->player != NULL)
-	{
-		if (abs(mo->standingslope->zdelta) < FRACUNIT/21)
-		{
-			// Don't slide on non-steep slopes.
-			// Changed in Ring Racers to only not apply physics on very slight slopes.
-			// (I think about 4 degree angles.)
-			return;
-		}
-
-		if (abs(mo->standingslope->zdelta) < FRACUNIT/2
-			&& !(mo->player->rmomx || mo->player->rmomy))
-		{
-			// Allow the player to stand still on slopes below a certain steepness.
-			// 45 degree angle steep, to be exact.
-			return; 
-		}
+		if (abs(mo->standingslope->zdelta) < FRACUNIT/2 && !(mo->player->rmomx || mo->player->rmomy))
+			return; // Allow the player to stand still on slopes below a certain steepness
 	}
 
-	thrust = FINESINE(mo->standingslope->zangle>>ANGLETOFINESHIFT) * 5 / 4 * (mo->eflags & MFE_VERTICALFLIP ? 1 : -1);
+	thrust = FINESINE(mo->standingslope->zangle>>ANGLETOFINESHIFT) * 15 / 16 * (mo->eflags & MFE_VERTICALFLIP ? 1 : -1);
 
 	if (mo->player) {
-		fixed_t mult = FRACUNIT;
+		fixed_t mult = 0;
 		if (mo->momx || mo->momy) {
 			angle_t angle = R_PointToAngle2(0, 0, mo->momx, mo->momy) - mo->standingslope->xydirection;
 
 			if (P_MobjFlip(mo) * mo->standingslope->zdelta < 0)
 				angle ^= ANGLE_180;
 
-			mult = FRACUNIT + (FRACUNIT + FINECOSINE(angle>>ANGLETOFINESHIFT))*4/3;
+			mult = FINECOSINE(angle >> ANGLETOFINESHIFT);
 		}
 
-		thrust = FixedMul(thrust, mult);
+		thrust = FixedMul(thrust, FRACUNIT*2/3 + mult/8);
 	}
 
+	if (mo->momx || mo->momy) // Slightly increase thrust based on the object's speed
+		thrust = FixedMul(thrust, FRACUNIT+P_AproxDistance(mo->momx, mo->momy)/16);
+	// This makes it harder to zigzag up steep slopes, as well as allows greater top speed when rolling down
+
 	// Let's get the gravity strength for the object...
 	thrust = FixedMul(thrust, abs(P_GetMobjGravity(mo)));