![\"smallest_sphere_for_points\"](\"https:\/\/i0.wp.com\/unitycoder.com\/blog\/wp-content\/uploads\/2013\/01\/smallest_sphere_for_points.jpg?resize=680%2C361\")
<\/p>\n<\/p>\n
While looking into this 2D shadows topic<\/a>, converted this BoundingSphere code<\/a> to unity (actually it wouldnt need to be in 3D..) It resizes the sphere, so that all the vertices fit inside. (for some reason, some objects fail still, see image below) Version 1.0 source:<\/strong><\/p>\n While looking into this 2D shadows topic, converted this BoundingSphere code to unity (actually it wouldnt need to be in 3D..) This could be also useful for creating & resizing sphere colliders.. It resizes the sphere, so that all the vertices fit inside. (for some […]<\/p>\n","protected":false},"author":1,"featured_media":1550,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[4,3],"tags":[390,392,391],"class_list":["post-1549","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-demos","category-unity3d","tag-bounding-sphere","tag-enclosing-sphere","tag-smallest-sphere"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/unitycoder.com\/blog\/wp-content\/uploads\/2013\/01\/smallest_sphere_for_points.jpg?fit=680%2C361&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p1KTaT-oZ","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/posts\/1549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/comments?post=1549"}],"version-history":[{"count":5,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/posts\/1549\/revisions"}],"predecessor-version":[{"id":1556,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/posts\/1549\/revisions\/1556"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/media\/1550"}],"wp:attachment":[{"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/media?parent=1549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/categories?post=1549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/unitycoder.com\/blog\/wp-json\/wp\/v2\/tags?post=1549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nThis could be also useful for creating & resizing sphere colliders..<\/p>\n
\n![\"smallest_sphere_for_points_bound_fail\"](\"https:\/\/i0.wp.com\/unitycoder.com\/blog\/wp-content\/uploads\/2013\/01\/smallest_sphere_for_points_bound_fail.jpg?resize=300%2C356\")
<\/p>\n\r\nusing UnityEngine;\r\nusing System.Collections;\r\n\r\npublic class SmallestSphere : MonoBehaviour {\r\nprivate float _radius;\r\nprivate Vector3 _center;\r\n\/\/For welzl calculations\r\nprivate const float RadiusEpsilon = 1.00001f;\r\nprivate GameObject sphere;\r\n\r\nvoid Start () {\r\nMesh mesh = GetComponent<MeshFilter>().mesh;\r\nVector3[] vertices = mesh.vertices;\r\nint[] indices = mesh.triangles;\r\n\r\nsphere = GameObject.CreatePrimitive(PrimitiveType.Sphere);\r\n\r\nComputeFromPrimitives(vertices, indices);\r\n}\r\npublic float Radius {\r\nget {\r\nreturn _radius;\r\n}\r\nset {\r\n_radius = value;\r\n\/\/\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0Debug.Log("Set r="+value);\r\n}\r\n}\r\n\r\nvoid ComputeFromPrimitives(Vector3[] vertices, int[] indices)\r\n{\r\nVector3[] copy = new Vector3[indices.Length];\r\n\r\nfor(int i = 0; i < indices.Length; i++) {\r\ncopy[i] = transform.TransformPoint(vertices[indices[i]]); \/\/ test\r\n\/\/copy[i] = vertices[indices[i]];\r\n}\r\n\r\nCalculateWelzl(copy, copy.Length, 0, 0);\r\n}\r\n\r\n\/\/Welzl minimum bounding sphere algorithm\r\nvoid CalculateWelzl(Vector3[] points, int length, int supportCount, int index) {\r\nswitch(supportCount) {\r\ncase 0:\r\n_radius = 0;\r\n_center = Vector3.zero;\r\nbreak;\r\ncase 1:\r\n_radius = 1.0f - RadiusEpsilon;\r\n_center = points[index-1];\r\nbreak;\r\ncase 2:\r\n\r\nSetSphere(points[index-1], points[index-2]);\r\n\r\nbreak;\r\n\r\ncase 3:\r\nSetSphere(points[index-1], points[index-2], points[index-3]);\r\nbreak;\r\ncase 4:\r\nSetSphere(points[index-1], points[index-2], points[index-3], points[index-4]);\r\nreturn;\r\n}\r\n\r\nfor(int i = 0; i < length; i++)\r\n{\r\nVector3 comp = points[i + index];\r\nfloat distSqr;\r\n\r\ndistSqr = (comp-_center).sqrMagnitude;\r\n\r\nif(distSqr - (_radius * _radius) > RadiusEpsilon - 1.0f) {\r\nfor(int j = i; j > 0; j--) {\r\nVector3 a = points[j + index];\r\nVector3 b = points[j - 1 + index];\r\npoints[j + index] = b;\r\npoints[j - 1 + index] = a;\r\n}\r\nCalculateWelzl(points, i, supportCount + 1, index + 1);\r\n}\r\n}\r\n}\r\n\r\n\/\/For Welzl calc - 2 support points\r\nvoid SetSphere(Vector3 O, Vector3 A)\r\n{\r\nRadius = (float) System.Math.Sqrt(((A.x - O.x) * (A.x - O.x) + (A.y - O.y)\r\n* (A.y - O.y) + (A.z - O.z) * (A.z - O.z)) \/ 4.0f) + RadiusEpsilon - 1.0f;\r\nfloat x = (1 - .5f) * O.x + .5f * A.x;\r\nfloat y = (1 - .5f) * O.y + .5f * A.y;\r\nfloat z = (1 - .5f) * O.z + .5f * A.z;\r\n\r\n\/\/ TODO:\r\nSetCenter(x, y, z);\r\n\r\n}\r\n\r\n\/\/For Welzl calc - 3 support points\r\nvoid SetSphere(Vector3 O, Vector3 A, Vector3 B) {\r\nVector3 a = A - O;\r\nVector3 b = B - O;\r\nVector3 aCrossB = Vector3.Cross(a, b);\r\nfloat denom = 2.0f * Vector3.Dot(aCrossB, aCrossB);\r\nif(denom == 0) {\r\n_center = Vector3.zero;\r\n_radius = 0;\r\n} else {\r\n\r\nVector3 o = ((Vector3.Cross(aCrossB, a) * b.sqrMagnitude)+ (Vector3.Cross(b, aCrossB) * a.sqrMagnitude)) \/ denom;\r\n_radius = o.magnitude * RadiusEpsilon;\r\n_center = O + o;\r\n}\r\n}\r\n\r\n\/\/For Welzl calc - 4 support points\r\nvoid SetSphere(Vector3 O, Vector3 A, Vector3 B, Vector3 C) {\r\nVector3 a = A - O;\r\nVector3 b = B - O;\r\nVector3 c = C - O;\r\n\r\nfloat denom = 2.0f * (a.x * (b.y * c.z - c.y * b.z) - b.x\r\n* (a.y * c.z - c.y * a.z) + c.x * (a.y * b.z - b.y * a.z));\r\nif(denom == 0) {\r\n_center = Vector3.zero;\r\n_radius = 0;\r\n} else {\r\nVector3 o = ((Vector3.Cross(a, b) * c.sqrMagnitude)\r\n+ (Vector3.Cross(c, a) * b.sqrMagnitude)\r\n+ (Vector3.Cross(b, c) * a.sqrMagnitude)) \/ denom;\r\n_radius = o.magnitude * RadiusEpsilon;\r\n_center = O + o;\r\n}\r\n}\r\n\r\nvoid SetCenter(float x,float y,float z)\r\n{\r\nsphere.transform.localScale = new Vector3(_radius*2,_radius*2,_radius*2);\r\nsphere.transform.position = new Vector3(x,y,z);\r\n}\r\n}\r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"