clusterizer: Remove redundant radius computation

Now that computeBoundingSphere is correct, we no longer need the
adjustment to the radius to ensure all spheres are covered.

Note that the resulting radius is subject to some floating-point errors,
so we can't necessarily replace the removed code with assertions, as the
containment of the spheres is true only with some floating point
tolerance.

Author: zeux

src/clusterizer.cpp

@@ -1009,23 +1009,10 @@ meshopt_Bounds meshopt_computeSphereBounds(const float* positions, size_t count,
 	float psphere[4] = {};
 	computeBoundingSphere(psphere, positions, count, positions_stride, radii ? radii : &rzero, radii ? radii_stride : 0);
 
-	float pradius = 0;
-
-	for (size_t i = 0; i < count; ++i)
-	{
-		const float* position = positions + i * (positions_stride / sizeof(float));
-		float radius = radii ? radii[i * (radii_stride / sizeof(float))] : 0;
-
-		float dx = position[0] - psphere[0], dy = position[1] - psphere[1], dz = position[2] - psphere[2];
-		float distance = sqrtf(dx * dx + dy * dy + dz * dz) + radius;
-
-		pradius = pradius < distance ? distance : pradius;
-	}
-
 	bounds.center[0] = psphere[0];
 	bounds.center[1] = psphere[1];
 	bounds.center[2] = psphere[2];
-	bounds.radius = pradius;
+	bounds.radius = psphere[3];
 
 	return bounds;
 }