From f0d1813752c31421163ae417b67f21b5fa57b391 Mon Sep 17 00:00:00 2001
From: toaster <rollerorbital@gmail.com>
Date: Mon, 16 Oct 2023 18:04:23 +0100
Subject: [PATCH] UCRP_TRACKHAZARD: Optimise implementation to not be 100
 booleans

Much like player->availabilities, use a set of bits on UINT8.
---
 src/d_player.h |  2 +-
 src/m_cond.c   | 56 ++++++++++++++++++++++++++++++++++++++------------
 src/p_inter.c  | 11 ++++++----
 3 files changed, 51 insertions(+), 18 deletions(-)

diff --git a/src/d_player.h b/src/d_player.h
index f0b3e4edc..548ed8f7c 100644
--- a/src/d_player.h
+++ b/src/d_player.h
@@ -402,7 +402,7 @@ struct roundconditions_t
 	boolean landmine_dunk;
 	boolean hit_midair;
 
-	boolean hittrackhazard[MAX_LAPS+1];
+	UINT8 hittrackhazard[((MAX_LAPS+1)/8) + 1];
 
 	mobjeflag_t wet_player;
 
diff --git a/src/m_cond.c b/src/m_cond.c
index 3f38e696a..6d867e254 100644
--- a/src/m_cond.c
+++ b/src/m_cond.c
@@ -1630,27 +1630,57 @@ boolean M_CheckCondition(condition_t *cn, player_t *player)
 			if (player->laps <= (requiredlap - cn->requirement))
 				return false;
 
-			const boolean desired = (cn->requirement == 1);
+			UINT8 requiredbit = 1<<(requiredlap & 7);
+			requiredlap /= 8;
+
 			if (cn->extrainfo1 == -1)
 			{
-				// Using cn->requirement as the first
-				// counted lap means that for conditions
-				// that require you to get hit every lap,
-				// that doesn't count POSITION -
-				// but if you can't get hit by a track
-				// hazard at all during the race,
-				// you're forbidden from getting hurt
-				// by a track hazard during POSITION.
-				for (; requiredlap >= cn->requirement; requiredlap--)
+				if (cn->requirement == 0)
 				{
-					if (player->roundconditions.hittrackhazard[requiredlap] != desired)
+					// The "don't get hit on any lap" check is trivial.
+					for (; requiredlap > 0; requiredlap--)
+					{
+						if (player->roundconditions.hittrackhazard[requiredlap] != 0)
+							return false;
+					}
+
+					return (player->roundconditions.hittrackhazard[0] == 0);
+				}
+
+				// The following is my attempt at a major optimisation.
+				// The naive version was MAX_LAP bools, which is ridiculous.
+
+				// Check the highest relevant byte for all necessary bits.
+				// We only do this if an == 0xFF/0xFE check wouldn't satisfy.
+				if (requiredbit != 7)
+				{
+					// Last bit MAYBE not needed, POSITION doesn't count.
+					const UINT8 finalbit = (requiredlap == 0) ? 1 : 0;
+					while (requiredbit != finalbit)
+					{
+						if (!(player->roundconditions.hittrackhazard[requiredlap] & requiredbit))
+							return false;
+						requiredbit /= 2;
+					}
+
+					if (requiredlap == 0)
+						return true;
+
+					requiredlap--;
+				}
+
+				// All bytes between the top and the bottom need to be checked for saturation.
+				for (; requiredlap > 0; requiredlap--)
+				{
+					if (player->roundconditions.hittrackhazard[requiredlap] != 0xFF)
 						return false;
 				}
 
-				return true;
+				// Last bit not needed, POSITION doesn't count.
+				return (player->roundconditions.hittrackhazard[0] == 0xFE);
 			}
 
-			return (player->roundconditions.hittrackhazard[requiredlap] == desired);
+			return (!(player->roundconditions.hittrackhazard[requiredlap] & requiredbit) != (cn->requirement == 1));
 		}
 
 		case UCRP_WETPLAYER:
diff --git a/src/p_inter.c b/src/p_inter.c
index 7b763ff62..6b2f248d8 100644
--- a/src/p_inter.c
+++ b/src/p_inter.c
@@ -2632,11 +2632,14 @@ boolean P_DamageMobj(mobj_t *target, mobj_t *inflictor, mobj_t *source, INT32 da
 		}
 		else if (!(inflictor && inflictor->player)
 			&& player->laps <= numlaps
-			&& damagetype != DMG_DEATHPIT
-			&& player->roundconditions.hittrackhazard[player->laps] == false)
+			&& damagetype != DMG_DEATHPIT)
 		{
-			player->roundconditions.hittrackhazard[player->laps] = true;
-			player->roundconditions.checkthisframe = true;
+			const UINT8 requiredbit = 1<<(player->laps & 7);
+			if (!(player->roundconditions.hittrackhazard[player->laps/8] & requiredbit))
+			{
+				player->roundconditions.hittrackhazard[player->laps/8] |= requiredbit;
+				player->roundconditions.checkthisframe = true;
+			}
 		}
 
 		// Instant-Death