From 9ad0af4479daa192bfacf67eb751a2c20186f804 Mon Sep 17 00:00:00 2001
From: Mitchell Richters <mjr4077au@gmail.com>
Date: Mon, 25 Sep 2023 16:39:12 +1000
Subject: [PATCH] - Blood: Better fix for view rolling under all circumstances.
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* Why is everything so difficult in Blood? 😕
* Do StrafeVel drag/resistance before `MoveDude()` as it may never be called if there's no velocity.
* Avoid using `mulscale16r()` in algorithm as we simply don't need to here.
* Move `doRollInput()` call into same area where drag is applied so all the code is concentrated in one spot.
---
 source/games/blood/src/actor.cpp  | 25 +++++++++++++++----------
 source/games/blood/src/player.cpp |  9 +++------
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/source/games/blood/src/actor.cpp b/source/games/blood/src/actor.cpp
index d511bda71..830376b12 100644
--- a/source/games/blood/src/actor.cpp
+++ b/source/games/blood/src/actor.cpp
@@ -5142,19 +5142,13 @@ void MoveDude(DBloodActor* actor)
 				return;
 			}
 		}
-		int nDrag = gDudeDrag;
-		if (actor->xspr.height > 0)
-			nDrag -= Scale(gDudeDrag, actor->xspr.height, 256);
-
-		if (pPlayer)
-		{
-			pPlayer->Angles.StrafeVel += FixedToFloat(-mulscale16r(FloatToFixed(pPlayer->Angles.StrafeVel), nDrag));
-		}
-
 		if (IsUnderwaterSector(actor->sector()))
 			return;
 		if (actor->xspr.height >= 0x100)
 			return;
+		int nDrag = gDudeDrag;
+		if (actor->xspr.height > 0)
+			nDrag -= Scale(gDudeDrag, actor->xspr.height, 256);
 
 		// this cannot be floatified due to the effect of mulscale16r on the value.
 		actor->vel.X += FixedToFloat(-mulscale16r(FloatToFixed(actor->vel.X), nDrag));
@@ -5163,7 +5157,6 @@ void MoveDude(DBloodActor* actor)
 		if (actor->vel.XY().Length() < 0.0625)
 		{
 			actor->vel.XY().Zero();
-			if (pPlayer) pPlayer->Angles.StrafeVel = 0;
 		}
 	}
 }
@@ -6053,6 +6046,18 @@ static void actCheckDudes()
 		if (pXSector && pXSector->Underwater) actAirDrag(actor, 5376);
 		else actAirDrag(actor, 128);
 
+		if (actor->IsPlayerActor())
+		{
+			PLAYER* pPlayer = &gPlayer[actor->spr.type - kDudePlayer1];
+			double nDrag = FixedToFloat(gDudeDrag);
+			if (actor->xspr.height > 0)
+				nDrag -= Scale(nDrag, (double)actor->xspr.height, 256.);
+
+			constexpr auto maxVel = (36211. / 3000.);
+			pPlayer->Angles.doRollInput(&pPlayer->input, actor->vel.XY(), maxVel, pPlayer->posture == kPostureSwim);
+			pPlayer->Angles.StrafeVel -= pPlayer->Angles.StrafeVel * nDrag;
+		}
+
 		if ((actor->spr.flags & 4) || !actor->vel.isZero() || actor->sector()->velFloor || actor->sector()->velCeil)
 			MoveDude(actor);
 	}
diff --git a/source/games/blood/src/player.cpp b/source/games/blood/src/player.cpp
index 3aad36a9c..f1831d2c7 100644
--- a/source/games/blood/src/player.cpp
+++ b/source/games/blood/src/player.cpp
@@ -1578,9 +1578,9 @@ void ProcessInput(PLAYER* pPlayer)
 
 	if ((pInput->fvel || pInput->svel) && (pPlayer->posture == 1 || actor->xspr.height < 256))
 	{
-		const double speed = pPlayer->posture == 1? 1. : 1. - (actor->xspr.height < 256 ? actor->xspr.height * (1. / 256.) : 0);
-		const double& fvAccel = pInput->fvel > 0 ? pPosture->frontAccel : pPosture->backAccel;
-		const double& svAccel = pPosture->sideAccel;
+		const double speed = pPlayer->posture == 1? 1. : 1. - (actor->xspr.height * (1. / 256.) * (actor->xspr.height < 256));
+		const double fvAccel = pInput->fvel > 0 ? pPosture->frontAccel : pPosture->backAccel;
+		const double svAccel = pPosture->sideAccel;
 		actor->vel.XY() += DVector2(pInput->fvel * fvAccel, pInput->svel * svAccel).Rotated(actor->spr.Angles.Yaw) * speed;
 		pPlayer->Angles.StrafeVel += pInput->svel * svAccel * speed;
 	}
@@ -1588,9 +1588,6 @@ void ProcessInput(PLAYER* pPlayer)
 	pPlayer->Angles.doViewYaw(pInput);
 	pPlayer->Angles.doYawInput(pInput);
 
-	constexpr auto maxVel = (36211. / 3000.);
-	pPlayer->Angles.doRollInput(pInput, actor->vel.XY(), maxVel, pPlayer->posture == kPostureSwim);
-
 	if (!(pInput->actions & SB_JUMP))
 		pPlayer->cantJump = 0;