From 30c38b7916f950ffd68b0605646021215adf5258 Mon Sep 17 00:00:00 2001
From: fo76utils <87907510+fo76utils@users.noreply.github.com>
Date: Tue, 16 Apr 2024 18:56:27 +0200
Subject: [PATCH] Use Miniball (https://github.com/hbf/miniball) in
 spUpdateBounds

---
 src/gl/gltools.cpp  | 15 ++++++++++++++-
 src/gl/gltools.h    |  2 +-
 src/spells/mesh.cpp |  4 ++--
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/gl/gltools.cpp b/src/gl/gltools.cpp
index 47a9bda0..8d3f0b5d 100644
--- a/src/gl/gltools.cpp
+++ b/src/gl/gltools.cpp
@@ -45,6 +45,7 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "libfo76utils/src/fp32vec4.hpp"
 #include "gamemanager.h"
+#include "miniball/Seb.h"
 
 //! \file gltools.cpp GL helper functions
 
@@ -177,7 +178,7 @@ BoundSphere::BoundSphere( const NifModel * nif, const QModelIndex & index )
 	radius = nif->get<float>( idx, "Radius" );
 }
 
-BoundSphere::BoundSphere( const QVector<Vector3> & verts )
+BoundSphere::BoundSphere( const QVector<Vector3> & verts, bool useMiniball )
 {
 	if ( verts.isEmpty() ) {
 		center = Vector3();
@@ -185,6 +186,18 @@ BoundSphere::BoundSphere( const QVector<Vector3> & verts )
 		return;
 	}
 
+	if ( useMiniball && verts.size() > 2 ) {
+		SEB_NAMESPACE::Smallest_enclosing_ball<float, Vector3, QVector<Vector3>>	mb( 3, verts );
+		auto	i = mb.center_begin();
+		center[0] = *i;
+		i++;
+		center[1] = *i;
+		i++;
+		center[2] = *i;
+		radius = mb.radius();
+		return;
+	}
+
 	// old algorithm: center of bounding sphere = bounds1 = centroid of verts
 	FloatVector4	bounds1( 0.0f );
 	// p1 and p2 are searched for Ritter's algorithm
diff --git a/src/gl/gltools.h b/src/gl/gltools.h
index 69c8df9c..05e40f7f 100644
--- a/src/gl/gltools.h
+++ b/src/gl/gltools.h
@@ -56,7 +56,7 @@ class BoundSphere final
 	BoundSphere( const BoundSphere & );
 	BoundSphere( const NifModel * nif, const QModelIndex & );
 	BoundSphere( const Vector3 & center, float radius );
-	BoundSphere( const QVector<Vector3> & vertices );
+	BoundSphere( const QVector<Vector3> & vertices, bool useMiniball = false );
 
 	Vector3 center;
 	float radius;
diff --git a/src/spells/mesh.cpp b/src/spells/mesh.cpp
index 6280100a..2155ea46 100644
--- a/src/spells/mesh.cpp
+++ b/src/spells/mesh.cpp
@@ -731,7 +731,7 @@ class spUpdateBounds final : public Spell
 			return index;
 
 		// Creating a bounding sphere from the verts
-		BoundSphere bounds = BoundSphere( verts );
+		BoundSphere bounds = BoundSphere( verts, true );
 		bounds.update( nif, index );
 
 		if ( nif->getBSVersion() >= 151 ) {
@@ -780,7 +780,7 @@ QModelIndex spUpdateBounds::cast_Starfield( NifModel * nif, const QModelIndex &
 		// FIXME: mesh flags are not updated
 		if ( meshFile.isValid() && meshFile.positions.size() > 0 && !boundsCalculated ) {
 			// Creating a bounding sphere and bounding box from the verts
-			bounds = BoundSphere( meshFile.positions );
+			bounds = BoundSphere( meshFile.positions, true );
 			calculateBoundingBox( bndCenter, bndDims, meshFile.positions );
 			boundsCalculated = true;
 		}