From 9e2b89e3860f7ca42a3dfcda37cf14d312a54341 Mon Sep 17 00:00:00 2001
From: Marco Hladik <marco@icculus.org>
Date: Thu, 20 Jan 2022 12:18:24 -0800
Subject: [PATCH] NSEntity: BBox will now account for rotation whenever
 SetModel() is used.

---
 src/gs-entbase/shared/NSEntity.h  |  1 +
 src/gs-entbase/shared/NSEntity.qc | 52 ++++++++++++++++++++++++++++---
 src/shared/math.h                 |  3 +-
 src/shared/math.qc                |  9 ++++++
 4 files changed, 59 insertions(+), 6 deletions(-)

diff --git a/src/gs-entbase/shared/NSEntity.h b/src/gs-entbase/shared/NSEntity.h
index df4ac400..964ab8a1 100644
--- a/src/gs-entbase/shared/NSEntity.h
+++ b/src/gs-entbase/shared/NSEntity.h
@@ -82,4 +82,5 @@ class NSEntity:NSTrigger
 	virtual void(vector, vector) SetSize;
 	virtual void(string, string) SpawnKey;
 	nonvirtual void(void) Destroy;
+	virtual void(void) UpdateBounds;
 };
diff --git a/src/gs-entbase/shared/NSEntity.qc b/src/gs-entbase/shared/NSEntity.qc
index 5bbb373a..f0401c26 100644
--- a/src/gs-entbase/shared/NSEntity.qc
+++ b/src/gs-entbase/shared/NSEntity.qc
@@ -283,6 +283,12 @@ NSEntity::SetSolid(float newSolid)
 	SetSendFlags(BASEFL_CHANGED_SOLID);
 }
 
+void
+NSEntity::UpdateBounds(void)
+{
+	SetSize(m_vecMins, m_vecMaxs);
+}
+
 void
 NSEntity::SetAngles(vector newAngles)
 {
@@ -291,20 +297,54 @@ NSEntity::SetAngles(vector newAngles)
 
 	angles = newAngles;
 	SetSendFlags(BASEFL_CHANGED_ANGLES);
+	UpdateBounds();
 }
+
 void
 NSEntity::SetSize(vector newMins, vector newMaxs)
 {
-	float sz = 1.0f;
+	float flScale = 1.0f;
+
 	m_vecMins = newMins;
 	m_vecMaxs = newMaxs;
 
-	if (scale != 0.0)
-		sz = scale;
+	/* avoid useless computation */
+	if (angles != [0,0,0]) {
+		/* adjust bbox according to rotation */
+		vector vecCorner[8];
+		newMins = newMaxs = [0,0,0];
+		for (int i = 0; i < 8; i++) {
+			vecCorner[i][0] = (i & 1) ? m_vecMins[0] : m_vecMaxs[0];
+			vecCorner[i][1] = (i & 2) ? m_vecMins[1] : m_vecMaxs[1];
+			vecCorner[i][2] = (i & 4) ? m_vecMins[2] : m_vecMaxs[2];
+			vecCorner[i] += origin;
+			vecCorner[i] = Math_RotateAroundPivot(vecCorner[i], origin, angles[1]);
+			vecCorner[i] -= origin;
 
-	setsize(this, m_vecMins * sz, m_vecMaxs * sz);
+			if (!(vecCorner[i][0] <= newMaxs[0]))
+				newMaxs[0] = vecCorner[i][0];
+			if (!(vecCorner[i][1] <= newMaxs[1]))
+				newMaxs[1] = vecCorner[i][1];
+			if (!(vecCorner[i][2] <= newMaxs[2]))
+				newMaxs[2] = vecCorner[i][2];
+
+    			if (!(vecCorner[i][0] >= newMins[0]))
+				newMins[0] = vecCorner[i][0];
+    			if (!(vecCorner[i][1] >= newMins[1]))
+				newMins[1] = vecCorner[i][1];
+    			if (!(vecCorner[i][2] >= newMins[2]))
+				newMins[2] = vecCorner[i][2];
+		}
+	}
+
+	/* 0.0 is never valid, if you want it to disappear do something else */
+	if (scale != 0.0)
+		flScale = scale;
+
+	setsize(this, newMins * flScale, newMaxs * flScale);
 	SetSendFlags(BASEFL_CHANGED_SIZE);
 }
+
 void
 NSEntity::SetOrigin(vector newOrigin)
 {
@@ -315,13 +355,15 @@ NSEntity::SetOrigin(vector newOrigin)
 	SetSendFlags(BASEFL_CHANGED_ORIGIN);
 }
 
-
 void
 NSEntity::SetModel(string newModel)
 {
 	model = newModel;
 	setmodel(this, newModel);
+
+	/* mins/maxs have been updated by setmodel */
 	SetSize(mins, maxs);
+
 	SetSendFlags(BASEFL_CHANGED_MODELINDEX);
 }
 void
diff --git a/src/shared/math.h b/src/shared/math.h
index 9dad9fc0..4d2ee63b 100644
--- a/src/shared/math.h
+++ b/src/shared/math.h
@@ -20,4 +20,5 @@ float Math_LerpAngle(float fStart, float fEnd, float fAmount);
 float Math_Lerp(float fA, float fB, float fPercent);
 float Math_FixDelta(float fDelta);
 vector Math_Reflect(vector v1, vector v2);
-vector Math_RandomVector(float flyup);
\ No newline at end of file
+vector Math_RandomVector(float flyup);
+vector Math_RotateAroundPivot(vector pos, vector pivot, float degr);
\ No newline at end of file
diff --git a/src/shared/math.qc b/src/shared/math.qc
index 67be39d5..c1408927 100644
--- a/src/shared/math.qc
+++ b/src/shared/math.qc
@@ -58,4 +58,13 @@ Math_RandomVector(float fFlyUp)
 	}
 
 	return tmp * 2.0f;
+}
+
+vector
+Math_RotateAroundPivot(vector pos, vector pivot, float degr)
+{
+	vector new = pos;
+	new[0] = pivot[0] + (pos[0] - pivot[0]) * cos(degr) - (pos[1] - pivot[1]) * sin(degr);
+	new[1] = pivot[1] + (pos[0] - pivot[0]) * sin(degr) + (pos[1] - pivot[1]) * cos(degr);
+	return new;
 }
\ No newline at end of file